From 578337b9fa26f735ad92696358f8fade02eab7d2 Mon Sep 17 00:00:00 2001
From: Duo Zhang <zhangduo@apache.org>
Date: Sun, 30 Jun 2024 23:41:27 +0800
Subject: [PATCH] HBASE-28684 Remove CellWrapper and use ExtendedCell
 internally in client side data structure

---
 .../mapreduce/MapReduceHFileSplitterJob.java  |   3 +-
 .../client/AsyncBatchRpcRetryingCaller.java   |  10 +-
 .../apache/hadoop/hbase/client/Delete.java    |  25 +-
 .../apache/hadoop/hbase/client/Increment.java |  10 +-
 .../apache/hadoop/hbase/client/Mutation.java  | 222 +++------------
 .../client/PackagePrivateFieldAccessor.java   |  11 +
 .../org/apache/hadoop/hbase/client/Put.java   |  21 +-
 .../apache/hadoop/hbase/client/Result.java    |  47 +++-
 .../org/apache/hadoop/hbase/ipc/Call.java     |  13 +-
 .../hadoop/hbase/ipc/CellBlockBuilder.java    |  18 +-
 .../ipc/DelegatingHBaseRpcController.java     |   8 +-
 .../hadoop/hbase/ipc/HBaseRpcController.java  |  12 +-
 .../hbase/ipc/HBaseRpcControllerImpl.java     |  25 +-
 .../hadoop/hbase/ipc/RpcConnection.java       |   4 +-
 .../hbase/ipc/RpcControllerFactory.java       |  12 +-
 .../hbase/shaded/protobuf/ProtobufUtil.java   |   5 +-
 .../shaded/protobuf/RequestConverter.java     |  38 +--
 .../hadoop/hbase/client/TestMutation.java     |  12 +-
 .../hbase/ipc/TestCellBlockBuilder.java       |  28 +-
 .../hbase/ipc/TestHBaseRpcControllerImpl.java |  30 ++-
 .../shaded/protobuf/TestProtobufUtil.java     |  11 +-
 .../hadoop/hbase/ByteBufferKeyValue.java      |   4 +-
 .../hadoop/hbase/CellComparatorImpl.java      |   2 +-
 .../org/apache/hadoop/hbase/CellUtil.java     |  25 +-
 .../hadoop/hbase/ExtendedCellScannable.java   |  37 +++
 .../hadoop/hbase/ExtendedCellScanner.java     |  37 +++
 .../org/apache/hadoop/hbase/KeyValue.java     |   4 +-
 .../apache/hadoop/hbase/KeyValueTestUtil.java |   7 +-
 .../org/apache/hadoop/hbase/KeyValueUtil.java |  11 +-
 .../apache/hadoop/hbase/PrivateCellUtil.java  | 254 ++++++++++++++----
 .../java/org/apache/hadoop/hbase/TagUtil.java |   6 +-
 .../hadoop/hbase/codec/BaseDecoder.java       |  10 +-
 .../hadoop/hbase/codec/BaseEncoder.java       |   4 +-
 .../apache/hadoop/hbase/codec/CellCodec.java  |   6 +-
 .../hadoop/hbase/codec/CellCodecWithTags.java |   6 +-
 .../org/apache/hadoop/hbase/codec/Codec.java  |   4 +-
 .../hadoop/hbase/codec/KeyValueCodec.java     |  14 +-
 .../hbase/codec/KeyValueCodecWithTags.java    |  10 +-
 .../hadoop/hbase/io/CellOutputStream.java     |   4 +-
 ...ner.java => SizedExtendedCellScanner.java} |   6 +-
 .../hbase/io/encoding/EncodedDataBlock.java   |   8 +-
 .../hadoop/hbase/io/encoding/NoneEncoder.java |   4 +-
 .../hadoop/hbase/TestCellComparator.java      |   2 +-
 .../org/apache/hadoop/hbase/TestCellUtil.java | 165 ++----------
 .../hadoop/hbase/codec/TestCellCodec.java     |  12 +-
 .../hbase/codec/TestCellCodecWithTags.java    |  16 +-
 .../codec/TestKeyValueCodecWithTags.java      |   4 +-
 .../client/TestRpcControllerFactory.java      |   9 +-
 .../hbase/mapreduce/CellSerialization.java    |   8 +-
 .../hbase/mapreduce/CellSortReducer.java      |  18 +-
 .../mapreduce/ExtendedCellSerialization.java  |   2 +-
 .../hbase/mapreduce/HFileOutputFormat2.java   |   4 +-
 .../apache/hadoop/hbase/mapreduce/Import.java |  30 ++-
 .../hadoop/hbase/mapreduce/PutCombiner.java   |  52 ++--
 .../hbase/mapreduce/PutSortReducer.java       |  11 +-
 .../hadoop/hbase/mapreduce/WALPlayer.java     |   3 +-
 .../hbase/util/MapReduceExtendedCell.java     |  21 +-
 .../mapreduce/TestHFileOutputFormat2.java     |   3 +-
 .../hbase/mapreduce/TestImportExport.java     |  22 +-
 .../AsyncRegionReplicationRetryingCaller.java |   4 +-
 .../hbase/client/AsyncRegionServerAdmin.java  |  11 +-
 .../hadoop/hbase/codec/MessageCodec.java      |   6 +-
 .../hbase/io/hfile/HFilePrettyPrinter.java    |   3 +-
 .../apache/hadoop/hbase/ipc/CallRunner.java   |   6 +-
 .../hadoop/hbase/ipc/NettyServerCall.java     |   4 +-
 .../hbase/ipc/NettyServerRpcConnection.java   |   4 +-
 .../org/apache/hadoop/hbase/ipc/RpcCall.java  |   7 +-
 .../apache/hadoop/hbase/ipc/RpcServer.java    |   3 +-
 .../hadoop/hbase/ipc/RpcServerInterface.java  |   5 +-
 .../apache/hadoop/hbase/ipc/ServerCall.java   |  12 +-
 .../hadoop/hbase/ipc/ServerRpcConnection.java |   6 +-
 .../hadoop/hbase/ipc/SimpleServerCall.java    |   4 +-
 .../hbase/ipc/SimpleServerRpcConnection.java  |   4 +-
 .../org/apache/hadoop/hbase/mob/MobUtils.java |   8 +-
 .../protobuf/ReplicationProtobufUtil.java     |  35 +--
 .../hadoop/hbase/regionserver/HRegion.java    |  22 +-
 .../regionserver/MobReferenceOnlyFilter.java  |   5 +-
 .../hbase/regionserver/RSRpcServices.java     |  29 +-
 .../regionserver/ReversedMobStoreScanner.java |   2 +-
 .../wal/AsyncProtobufLogWriter.java           |   3 +-
 .../regionserver/wal/ProtobufLogWriter.java   |   3 +-
 .../regionserver/wal/SecureWALCellCodec.java  |   5 +-
 .../hbase/regionserver/wal/WALCellCodec.java  |   8 +-
 .../ReplaySyncReplicationWALCallable.java     |   7 +-
 .../security/access/AccessController.java     |  12 +-
 .../hbase/security/access/AuthManager.java    |   5 +-
 .../security/access/PermissionStorage.java    |   3 +-
 ...estCustomPriorityRpcControllerFactory.java |   4 +-
 .../hbase/client/TestFromClientSide.java      |   5 +-
 .../client/TestIncrementsFromClientSide.java  |   5 +-
 .../client/TestMalformedCellFromClient.java   |   7 +-
 .../hadoop/hbase/codec/CodecPerformance.java  |  23 +-
 .../hbase/codec/TestCellMessageCodec.java     |  12 +-
 .../TestPostIncrementAndAppendBeforeWAL.java  |  13 +-
 .../hadoop/hbase/filter/TestFilterList.java   |   7 +-
 .../hbase/io/compress/HFileTestBase.java      |   4 +-
 .../TestBufferedDataBlockEncoder.java         |   8 +-
 .../io/encoding/TestDataBlockEncoders.java    |  10 +-
 .../hbase/io/hfile/TestHFileEncryption.java   |   4 +-
 .../io/hfile/TestScannerFromBucketCache.java  |  26 +-
 .../hfile/TestSeekBeforeWithInlineBlocks.java |   6 +-
 .../hadoop/hbase/io/hfile/TestSeekTo.java     |   3 +-
 .../hadoop/hbase/ipc/AbstractTestIPC.java     |  14 +-
 .../ipc/TestNettyChannelWritability.java      |  11 +-
 .../hbase/ipc/TestProtobufRpcServiceImpl.java |  12 +-
 .../hadoop/hbase/master/MockRegionServer.java |   9 +-
 .../hbase/mob/TestMobStoreCompaction.java     |  13 +-
 .../namequeues/TestNamedQueueRecorder.java    |   6 +-
 .../hbase/namequeues/TestRpcLogDetails.java   |   6 +-
 .../region/TestRegionProcedureStore.java      |   6 +-
 .../protobuf/TestReplicationProtobuf.java     |  10 +-
 .../regionserver/DataBlockEncodingTool.java   |  10 +-
 .../EncodedSeekPerformanceTest.java           |   5 +-
 .../hbase/regionserver/TestBlocksScanned.java |   6 +-
 .../hbase/regionserver/TestCellFlatSet.java   |  12 +-
 .../hbase/regionserver/TestHMobStore.java     |  12 +-
 .../hbase/regionserver/TestHRegion.java       |  33 +--
 .../TestHRegionServerBulkLoad.java            |   5 +-
 .../hadoop/hbase/regionserver/TestHStore.java |  34 +--
 .../hbase/regionserver/TestHStoreFile.java    |   5 +-
 .../hbase/regionserver/TestKeepDeletes.java   |  11 +-
 .../regionserver/TestMultiColumnScanner.java  |   9 +-
 .../regionserver/TestReplicateToReplica.java  |   4 +-
 ...estStoreFileScannerWithTagCompression.java |   4 +-
 .../hadoop/hbase/regionserver/TestTags.java   |  20 +-
 .../compactions/TestCompactor.java            |   4 +-
 .../replication/TestReplicationWithTags.java  |   5 +-
 ...ExpAsStringVisibilityLabelServiceImpl.java |   5 +-
 .../TestVisibilityLabelsReplication.java      |  12 +-
 .../hadoop/hbase/util/HFileTestUtil.java      |   3 +-
 .../hadoop/hbase/thrift2/ThriftUtilities.java |  16 +-
 131 files changed, 1064 insertions(+), 1011 deletions(-)
 create mode 100644 hbase-common/src/main/java/org/apache/hadoop/hbase/ExtendedCellScannable.java
 create mode 100644 hbase-common/src/main/java/org/apache/hadoop/hbase/ExtendedCellScanner.java
 rename hbase-common/src/main/java/org/apache/hadoop/hbase/io/{SizedCellScanner.java => SizedExtendedCellScanner.java} (85%)

diff --git a/hbase-backup/src/main/java/org/apache/hadoop/hbase/backup/mapreduce/MapReduceHFileSplitterJob.java b/hbase-backup/src/main/java/org/apache/hadoop/hbase/backup/mapreduce/MapReduceHFileSplitterJob.java
index 04180972885e..2c073c56f7eb 100644
--- a/hbase-backup/src/main/java/org/apache/hadoop/hbase/backup/mapreduce/MapReduceHFileSplitterJob.java
+++ b/hbase-backup/src/main/java/org/apache/hadoop/hbase/backup/mapreduce/MapReduceHFileSplitterJob.java
@@ -24,6 +24,7 @@
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.HBaseConfiguration;
+import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.TableName;
 import org.apache.hadoop.hbase.client.Connection;
 import org.apache.hadoop.hbase.client.ConnectionFactory;
@@ -76,7 +77,7 @@ static class HFileCellMapper extends Mapper<NullWritable, Cell, ImmutableBytesWr
     public void map(NullWritable key, Cell value, Context context)
       throws IOException, InterruptedException {
       context.write(new ImmutableBytesWritable(CellUtil.cloneRow(value)),
-        new MapReduceExtendedCell(value));
+        new MapReduceExtendedCell(PrivateCellUtil.ensureExtendedCell(value)));
     }
 
     @Override
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncBatchRpcRetryingCaller.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncBatchRpcRetryingCaller.java
index 4b28d4cd4e2d..18d54fd300bc 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncBatchRpcRetryingCaller.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncBatchRpcRetryingCaller.java
@@ -17,7 +17,6 @@
  */
 package org.apache.hadoop.hbase.client;
 
-import static org.apache.hadoop.hbase.CellUtil.createCellScanner;
 import static org.apache.hadoop.hbase.client.ConnectionUtils.calcPriority;
 import static org.apache.hadoop.hbase.client.ConnectionUtils.resetController;
 import static org.apache.hadoop.hbase.client.ConnectionUtils.translateException;
@@ -44,11 +43,12 @@
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 import org.apache.commons.lang3.mutable.MutableBoolean;
-import org.apache.hadoop.hbase.CellScannable;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
+import org.apache.hadoop.hbase.ExtendedCellScannable;
 import org.apache.hadoop.hbase.HBaseServerException;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.HRegionLocation;
+import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.RetryImmediatelyException;
 import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.TableName;
@@ -274,7 +274,7 @@ private void failAll(Stream<Action> actions, int tries) {
   }
 
   private ClientProtos.MultiRequest buildReq(Map<byte[], RegionRequest> actionsByRegion,
-    List<CellScannable> cells, Map<Integer, Integer> indexMap) throws IOException {
+    List<ExtendedCellScannable> cells, Map<Integer, Integer> indexMap) throws IOException {
     ClientProtos.MultiRequest.Builder multiRequestBuilder = ClientProtos.MultiRequest.newBuilder();
     ClientProtos.RegionAction.Builder regionActionBuilder = ClientProtos.RegionAction.newBuilder();
     ClientProtos.Action.Builder actionBuilder = ClientProtos.Action.newBuilder();
@@ -382,7 +382,7 @@ private void sendToServer(ServerName serverName, ServerRequest serverReq, int tr
       return;
     }
     ClientProtos.MultiRequest req;
-    List<CellScannable> cells = new ArrayList<>();
+    List<ExtendedCellScannable> cells = new ArrayList<>();
     // Map from a created RegionAction to the original index for a RowMutations within
     // the original list of actions. This will be used to process the results when there
     // is RowMutations/CheckAndMutate in the action list.
@@ -398,7 +398,7 @@ private void sendToServer(ServerName serverName, ServerRequest serverReq, int tr
       calcPriority(serverReq.getPriority(), tableName), tableName);
     controller.setRequestAttributes(requestAttributes);
     if (!cells.isEmpty()) {
-      controller.setCellScanner(createCellScanner(cells));
+      controller.setCellScanner(PrivateCellUtil.createExtendedCellScanner(cells));
     }
     stub.multi(controller, req, resp -> {
       if (controller.failed()) {
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Delete.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Delete.java
index f97db8a116d6..65ac34e4a0ed 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Delete.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Delete.java
@@ -25,6 +25,7 @@
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellBuilder;
 import org.apache.hadoop.hbase.CellBuilderType;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.security.access.Permission;
@@ -171,10 +172,8 @@ public Delete addFamily(final byte[] family) {
    * @return this for invocation chaining
    */
   public Delete addFamily(final byte[] family, final long timestamp) {
-    if (timestamp < 0) {
-      throw new IllegalArgumentException("Timestamp cannot be negative. ts=" + timestamp);
-    }
-    List<Cell> list = getCellList(family);
+    checkTimestamp(ts);
+    List<ExtendedCell> list = getCellList(family);
     if (!list.isEmpty()) {
       list.clear();
     }
@@ -190,10 +189,8 @@ public Delete addFamily(final byte[] family, final long timestamp) {
    * @return this for invocation chaining
    */
   public Delete addFamilyVersion(final byte[] family, final long timestamp) {
-    if (timestamp < 0) {
-      throw new IllegalArgumentException("Timestamp cannot be negative. ts=" + timestamp);
-    }
-    List<Cell> list = getCellList(family);
+    checkTimestamp(ts);
+    List<ExtendedCell> list = getCellList(family);
     list.add(new KeyValue(row, family, null, timestamp, KeyValue.Type.DeleteFamilyVersion));
     return this;
   }
@@ -218,10 +215,8 @@ public Delete addColumns(final byte[] family, final byte[] qualifier) {
    * @return this for invocation chaining
    */
   public Delete addColumns(final byte[] family, final byte[] qualifier, final long timestamp) {
-    if (timestamp < 0) {
-      throw new IllegalArgumentException("Timestamp cannot be negative. ts=" + timestamp);
-    }
-    List<Cell> list = getCellList(family);
+    checkTimestamp(ts);
+    List<ExtendedCell> list = getCellList(family);
     list.add(new KeyValue(this.row, family, qualifier, timestamp, KeyValue.Type.DeleteColumn));
     return this;
   }
@@ -247,10 +242,8 @@ public Delete addColumn(final byte[] family, final byte[] qualifier) {
    * @return this for invocation chaining
    */
   public Delete addColumn(byte[] family, byte[] qualifier, long timestamp) {
-    if (timestamp < 0) {
-      throw new IllegalArgumentException("Timestamp cannot be negative. ts=" + timestamp);
-    }
-    List<Cell> list = getCellList(family);
+    checkTimestamp(ts);
+    List<ExtendedCell> list = getCellList(family);
     KeyValue kv = new KeyValue(this.row, family, qualifier, timestamp, KeyValue.Type.Delete);
     list.add(kv);
     return this;
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Increment.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Increment.java
index aad853f8c06c..fc03180f5200 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Increment.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Increment.java
@@ -21,12 +21,14 @@
 import java.util.List;
 import java.util.Map;
 import java.util.NavigableMap;
+import java.util.Objects;
 import java.util.TreeMap;
 import java.util.UUID;
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellBuilder;
 import org.apache.hadoop.hbase.CellBuilderType;
 import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.io.TimeRange;
 import org.apache.hadoop.hbase.security.access.Permission;
@@ -114,10 +116,8 @@ public Increment add(Cell cell) throws IOException {
    * @return the Increment object
    */
   public Increment addColumn(byte[] family, byte[] qualifier, long amount) {
-    if (family == null) {
-      throw new IllegalArgumentException("family cannot be null");
-    }
-    List<Cell> list = getCellList(family);
+    Objects.requireNonNull(family, "family cannot be null");
+    List<ExtendedCell> list = getCellList(family);
     KeyValue kv = createPutKeyValue(family, qualifier, ts, Bytes.toBytes(amount));
     list.add(kv);
     return this;
@@ -224,7 +224,7 @@ public String toString() {
     }
     sb.append(", families=");
     boolean moreThanOne = false;
-    for (Map.Entry<byte[], List<Cell>> entry : this.familyMap.entrySet()) {
+    for (Map.Entry<byte[], List<ExtendedCell>> entry : this.familyMap.entrySet()) {
       if (moreThanOne) {
         sb.append("), ");
       } else {
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Mutation.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Mutation.java
index 0be0325d499f..349857fadb10 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Mutation.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Mutation.java
@@ -22,11 +22,9 @@
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashMap;
-import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.NavigableMap;
-import java.util.Optional;
 import java.util.TreeMap;
 import java.util.UUID;
 import java.util.stream.Collectors;
@@ -34,10 +32,10 @@
 import org.apache.hadoop.hbase.CellBuilder;
 import org.apache.hadoop.hbase.CellBuilderFactory;
 import org.apache.hadoop.hbase.CellBuilderType;
-import org.apache.hadoop.hbase.CellScannable;
-import org.apache.hadoop.hbase.CellScanner;
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.ExtendedCell;
+import org.apache.hadoop.hbase.ExtendedCellScannable;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.IndividualBytesFieldCell;
 import org.apache.hadoop.hbase.KeyValue;
@@ -66,7 +64,7 @@
 
 @InterfaceAudience.Public
 public abstract class Mutation extends OperationWithAttributes
-  implements Row, CellScannable, HeapSize {
+  implements Row, ExtendedCellScannable, HeapSize {
   public static final long MUTATION_OVERHEAD = ClassSize.align(
     // This
     ClassSize.OBJECT +
@@ -96,13 +94,12 @@ public abstract class Mutation extends OperationWithAttributes
   private static final String RETURN_RESULTS = "_rr_";
 
   // TODO: row should be final
-  protected byte[] row = null;
+  protected byte[] row;
   protected long ts = HConstants.LATEST_TIMESTAMP;
   protected Durability durability = Durability.USE_DEFAULT;
 
-  // TODO: familyMap should be final
   // A Map sorted by column family.
-  protected NavigableMap<byte[], List<Cell>> familyMap;
+  protected final NavigableMap<byte[], List<ExtendedCell>> familyMap;
 
   /**
    * empty construction. We need this empty construction to keep binary compatibility.
@@ -115,7 +112,7 @@ protected Mutation(Mutation clone) {
     super(clone);
     this.row = clone.getRow();
     this.ts = clone.getTimestamp();
-    this.familyMap = clone.getFamilyCellMap().entrySet().stream()
+    this.familyMap = clone.familyMap.entrySet().stream()
       .collect(Collectors.toMap(e -> e.getKey(), e -> new ArrayList<>(e.getValue()), (k, v) -> {
         throw new RuntimeException("collisions!!!");
       }, () -> new TreeMap<>(Bytes.BYTES_COMPARATOR)));
@@ -127,18 +124,23 @@ protected Mutation(Mutation clone) {
    * @param ts        timestamp
    * @param familyMap the map to collect all cells internally. CAN'T be null
    */
+  @SuppressWarnings({ "unchecked", "rawtypes" })
   protected Mutation(byte[] row, long ts, NavigableMap<byte[], List<Cell>> familyMap) {
     this.row = Preconditions.checkNotNull(row);
-    if (row.length == 0) {
-      throw new IllegalArgumentException("Row can't be empty");
-    }
+    Preconditions.checkArgument(row.length > 0, "Row can't be empty");
     this.ts = ts;
-    this.familyMap = Preconditions.checkNotNull(familyMap);
+    // We do not allow other Cell types in HBase so here we just do a simple cast
+    this.familyMap = (NavigableMap) Preconditions.checkNotNull(familyMap);
   }
 
+  /**
+   * For client users: You should only use the return value as a
+   * {@link org.apache.hadoop.hbase.CellScanner}, {@link ExtendedCellScanner} is marked as
+   * IA.Private which means there is no guarantee about its API stability.
+   */
   @Override
-  public CellScanner cellScanner() {
-    return CellUtil.createCellScanner(getFamilyCellMap());
+  public ExtendedCellScanner cellScanner() {
+    return PrivateCellUtil.createExtendedCellScanner(familyMap);
   }
 
   /**
@@ -147,13 +149,8 @@ public CellScanner cellScanner() {
    * @param family column family
    * @return a list of Cell objects, returns an empty list if one doesn't exist.
    */
-  List<Cell> getCellList(byte[] family) {
-    List<Cell> list = getFamilyCellMap().get(family);
-    if (list == null) {
-      list = new ArrayList<>();
-      getFamilyCellMap().put(family, list);
-    }
-    return list;
+  List<ExtendedCell> getCellList(byte[] family) {
+    return familyMap.computeIfAbsent(family, k -> new ArrayList<>());
   }
 
   /**
@@ -218,7 +215,7 @@ public Map<String, Object> toMap(int maxCols) {
     map.put("row", Bytes.toStringBinary(this.row));
     int colCount = 0;
     // iterate through all column families affected
-    for (Map.Entry<byte[], List<Cell>> entry : getFamilyCellMap().entrySet()) {
+    for (Map.Entry<byte[], List<ExtendedCell>> entry : familyMap.entrySet()) {
       // map from this family to details for each cell affected within the family
       List<Map<String, Object>> qualifierDetails = new ArrayList<>();
       columns.put(Bytes.toStringBinary(entry.getKey()), qualifierDetails);
@@ -227,7 +224,7 @@ public Map<String, Object> toMap(int maxCols) {
         continue;
       }
       // add details for each cell
-      for (Cell cell : entry.getValue()) {
+      for (ExtendedCell cell : entry.getValue()) {
         if (--maxCols <= 0) {
           continue;
         }
@@ -250,7 +247,7 @@ public Map<String, Object> toMap(int maxCols) {
     return map;
   }
 
-  private static Map<String, Object> cellToStringMap(Cell c) {
+  private static Map<String, Object> cellToStringMap(ExtendedCell c) {
     Map<String, Object> stringMap = new HashMap<>();
     stringMap.put("qualifier",
       Bytes.toStringBinary(c.getQualifierArray(), c.getQualifierOffset(), c.getQualifierLength()));
@@ -283,8 +280,9 @@ public Durability getDurability() {
   /**
    * Method for retrieving the put's familyMap
    */
+  @SuppressWarnings({ "unchecked", "rawtypes" })
   public NavigableMap<byte[], List<Cell>> getFamilyCellMap() {
-    return this.familyMap;
+    return (NavigableMap) this.familyMap;
   }
 
   /**
@@ -517,9 +515,7 @@ protected long extraHeapSize() {
    * Set the timestamp of the delete.
    */
   public Mutation setTimestamp(long timestamp) {
-    if (timestamp < 0) {
-      throw new IllegalArgumentException("Timestamp cannot be negative. ts=" + timestamp);
-    }
+    checkTimestamp(ts);
     this.ts = timestamp;
     return this;
   }
@@ -603,7 +599,7 @@ public List<Cell> get(byte[] family, byte[] qualifier) {
    */
   protected boolean has(byte[] family, byte[] qualifier, long ts, byte[] value, boolean ignoreTS,
     boolean ignoreValue) {
-    List<Cell> list = getCellList(family);
+    List<ExtendedCell> list = getCellList(family);
     if (list.isEmpty()) {
       return false;
     }
@@ -613,7 +609,7 @@ protected boolean has(byte[] family, byte[] qualifier, long ts, byte[] value, bo
     // F T => 2
     // F F => 1
     if (!ignoreTS && !ignoreValue) {
-      for (Cell cell : list) {
+      for (ExtendedCell cell : list) {
         if (
           CellUtil.matchingFamily(cell, family) && CellUtil.matchingQualifier(cell, qualifier)
             && CellUtil.matchingValue(cell, value) && cell.getTimestamp() == ts
@@ -692,6 +688,10 @@ static void checkRow(ByteBuffer row) {
     }
   }
 
+  protected final void checkTimestamp(long ts) {
+    Preconditions.checkArgument(ts >= 0, "Timestamp cannot be negative. ts=%s", ts);
+  }
+
   Mutation add(Cell cell) throws IOException {
     // Checking that the row of the kv is the same as the mutation
     // TODO: It is fraught with risk if user pass the wrong row.
@@ -714,9 +714,9 @@ Mutation add(Cell cell) throws IOException {
     }
 
     if (cell instanceof ExtendedCell) {
-      getCellList(family).add(cell);
+      getCellList(family).add((ExtendedCell) cell);
     } else {
-      getCellList(family).add(new CellWrapper(cell));
+      throw new IllegalArgumentException("Unsupported cell type: " + cell.getClass().getName());
     }
     return this;
   }
@@ -743,7 +743,7 @@ public CellBuilder getCellBuilder() {
    * @param cellType        e.g Cell.Type.Put
    * @return CellBuilder which already has relevant Type and Row set.
    */
-  protected CellBuilder getCellBuilder(CellBuilderType cellBuilderType, Cell.Type cellType) {
+  protected final CellBuilder getCellBuilder(CellBuilderType cellBuilderType, Cell.Type cellType) {
     CellBuilder builder = CellBuilderFactory.create(cellBuilderType).setRow(row).setType(cellType);
     return new CellBuilder() {
       @Override
@@ -818,158 +818,4 @@ public CellBuilder clear() {
       }
     };
   }
-
-  private static final class CellWrapper implements ExtendedCell {
-    private static final long FIXED_OVERHEAD = ClassSize.align(ClassSize.OBJECT // object header
-      + KeyValue.TIMESTAMP_SIZE // timestamp
-      + Bytes.SIZEOF_LONG // sequence id
-      + 1 * ClassSize.REFERENCE); // references to cell
-    private final Cell cell;
-    private long sequenceId;
-    private long timestamp;
-
-    CellWrapper(Cell cell) {
-      assert !(cell instanceof ExtendedCell);
-      this.cell = cell;
-      this.sequenceId = cell.getSequenceId();
-      this.timestamp = cell.getTimestamp();
-    }
-
-    @Override
-    public void setSequenceId(long seqId) {
-      sequenceId = seqId;
-    }
-
-    @Override
-    public void setTimestamp(long ts) {
-      timestamp = ts;
-    }
-
-    @Override
-    public void setTimestamp(byte[] ts) {
-      timestamp = Bytes.toLong(ts);
-    }
-
-    @Override
-    public long getSequenceId() {
-      return sequenceId;
-    }
-
-    @Override
-    public byte[] getValueArray() {
-      return cell.getValueArray();
-    }
-
-    @Override
-    public int getValueOffset() {
-      return cell.getValueOffset();
-    }
-
-    @Override
-    public int getValueLength() {
-      return cell.getValueLength();
-    }
-
-    @Override
-    public byte[] getTagsArray() {
-      return cell.getTagsArray();
-    }
-
-    @Override
-    public int getTagsOffset() {
-      return cell.getTagsOffset();
-    }
-
-    @Override
-    public int getTagsLength() {
-      return cell.getTagsLength();
-    }
-
-    @Override
-    public byte[] getRowArray() {
-      return cell.getRowArray();
-    }
-
-    @Override
-    public int getRowOffset() {
-      return cell.getRowOffset();
-    }
-
-    @Override
-    public short getRowLength() {
-      return cell.getRowLength();
-    }
-
-    @Override
-    public byte[] getFamilyArray() {
-      return cell.getFamilyArray();
-    }
-
-    @Override
-    public int getFamilyOffset() {
-      return cell.getFamilyOffset();
-    }
-
-    @Override
-    public byte getFamilyLength() {
-      return cell.getFamilyLength();
-    }
-
-    @Override
-    public byte[] getQualifierArray() {
-      return cell.getQualifierArray();
-    }
-
-    @Override
-    public int getQualifierOffset() {
-      return cell.getQualifierOffset();
-    }
-
-    @Override
-    public int getQualifierLength() {
-      return cell.getQualifierLength();
-    }
-
-    @Override
-    public long getTimestamp() {
-      return timestamp;
-    }
-
-    @Override
-    public byte getTypeByte() {
-      return cell.getTypeByte();
-    }
-
-    @Override
-    public Optional<Tag> getTag(byte type) {
-      return PrivateCellUtil.getTag(cell, type);
-    }
-
-    @Override
-    public Iterator<Tag> getTags() {
-      return PrivateCellUtil.tagsIterator(cell);
-    }
-
-    @Override
-    public byte[] cloneTags() {
-      return PrivateCellUtil.cloneTags(cell);
-    }
-
-    private long heapOverhead() {
-      return FIXED_OVERHEAD + ClassSize.ARRAY // row
-        + getFamilyLength() == 0
-        ? 0
-        : ClassSize.ARRAY + getQualifierLength() == 0 ? 0
-        : ClassSize.ARRAY + getValueLength() == 0 ? 0
-        : ClassSize.ARRAY + getTagsLength() == 0 ? 0
-        : ClassSize.ARRAY;
-    }
-
-    @Override
-    public long heapSize() {
-      return heapOverhead() + ClassSize.align(getRowLength()) + ClassSize.align(getFamilyLength())
-        + ClassSize.align(getQualifierLength()) + ClassSize.align(getValueLength())
-        + ClassSize.align(getTagsLength());
-    }
-  }
 }
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/PackagePrivateFieldAccessor.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/PackagePrivateFieldAccessor.java
index 56a8dd19fcc5..2f70fd692086 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/PackagePrivateFieldAccessor.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/PackagePrivateFieldAccessor.java
@@ -17,6 +17,9 @@
  */
 package org.apache.hadoop.hbase.client;
 
+import java.util.List;
+import java.util.NavigableMap;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.yetus.audience.InterfaceAudience;
 
 /**
@@ -38,4 +41,12 @@ public static void setMvccReadPoint(Scan scan, long mvccReadPoint) {
   public static long getMvccReadPoint(Scan scan) {
     return scan.getMvccReadPoint();
   }
+
+  public static ExtendedCell[] getExtendedRawCells(Result result) {
+    return result.rawExtendedCells();
+  }
+
+  public static NavigableMap<byte[], List<ExtendedCell>> getExtendedFamilyCellMap(Mutation m) {
+    return m.familyMap;
+  }
 }
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Put.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Put.java
index dc470069f90c..b97a023c3899 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Put.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Put.java
@@ -26,6 +26,7 @@
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellBuilder;
 import org.apache.hadoop.hbase.CellBuilderType;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.io.HeapSize;
@@ -93,11 +94,9 @@ public Put(ByteBuffer row) {
    */
   public Put(byte[] rowArray, int rowOffset, int rowLength, long ts) {
     checkRow(rowArray, rowOffset, rowLength);
+    checkTimestamp(ts);
     this.row = Bytes.copy(rowArray, rowOffset, rowLength);
     this.ts = ts;
-    if (ts < 0) {
-      throw new IllegalArgumentException("Timestamp cannot be negative. ts=" + ts);
-    }
   }
 
   /**
@@ -119,9 +118,7 @@ public Put(byte[] row, boolean rowIsImmutable) {
    */
   public Put(byte[] row, long ts, boolean rowIsImmutable) {
     // Check and set timestamp
-    if (ts < 0) {
-      throw new IllegalArgumentException("Timestamp cannot be negative. ts=" + ts);
-    }
+    checkTimestamp(ts);
     this.ts = ts;
 
     // Deal with row according to rowIsImmutable
@@ -171,10 +168,8 @@ public Put addColumn(byte[] family, byte[] qualifier, byte[] value) {
    * @param value     column value
    */
   public Put addColumn(byte[] family, byte[] qualifier, long ts, byte[] value) {
-    if (ts < 0) {
-      throw new IllegalArgumentException("Timestamp cannot be negative. ts=" + ts);
-    }
-    List<Cell> list = getCellList(family);
+    checkTimestamp(ts);
+    List<ExtendedCell> list = getCellList(family);
     KeyValue kv = createPutKeyValue(family, qualifier, ts, value);
     list.add(kv);
     return this;
@@ -189,10 +184,8 @@ public Put addColumn(byte[] family, byte[] qualifier, long ts, byte[] value) {
    * @param value     column value
    */
   public Put addColumn(byte[] family, ByteBuffer qualifier, long ts, ByteBuffer value) {
-    if (ts < 0) {
-      throw new IllegalArgumentException("Timestamp cannot be negative. ts=" + ts);
-    }
-    List<Cell> list = getCellList(family);
+    checkTimestamp(ts);
+    List<ExtendedCell> list = getCellList(family);
     KeyValue kv = createPutKeyValue(family, qualifier, ts, value, null);
     list.add(kv);
     return this;
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Result.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Result.java
index ec1d3f2b1fab..ba866812b889 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Result.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Result.java
@@ -32,9 +32,11 @@
 import java.util.TreeMap;
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellComparator;
-import org.apache.hadoop.hbase.CellScannable;
 import org.apache.hadoop.hbase.CellScanner;
 import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.ExtendedCell;
+import org.apache.hadoop.hbase.ExtendedCellScannable;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.KeyValueUtil;
@@ -70,8 +72,8 @@
  * {@link #copyFrom(Result)}
  */
 @InterfaceAudience.Public
-public class Result implements CellScannable, CellScanner {
-  private Cell[] cells;
+public class Result implements ExtendedCellScannable, ExtendedCellScanner {
+  private ExtendedCell[] cells;
   private Boolean exists; // if the query was just to check existence.
   private boolean stale = false;
 
@@ -142,7 +144,8 @@ public static Result create(List<? extends Cell> cells, Boolean exists, boolean
     if (exists != null) {
       return new Result(null, exists, stale, mayHaveMoreCellsInRow);
     }
-    return new Result(cells.toArray(new Cell[cells.size()]), null, stale, mayHaveMoreCellsInRow);
+    return new Result(cells.toArray(new ExtendedCell[cells.size()]), null, stale,
+      mayHaveMoreCellsInRow);
   }
 
   /**
@@ -163,7 +166,7 @@ public static Result create(Cell[] cells, Boolean exists, boolean stale,
     if (exists != null) {
       return new Result(null, exists, stale, mayHaveMoreCellsInRow);
     }
-    return new Result(cells, null, stale, mayHaveMoreCellsInRow);
+    return new Result((ExtendedCell[]) cells, null, stale, mayHaveMoreCellsInRow);
   }
 
   public static Result createCursorResult(Cursor cursor) {
@@ -176,7 +179,8 @@ private Result(Cursor cursor) {
   }
 
   /** Private ctor. Use {@link #create(Cell[])}. */
-  private Result(Cell[] cells, Boolean exists, boolean stale, boolean mayHaveMoreCellsInRow) {
+  private Result(ExtendedCell[] cells, Boolean exists, boolean stale,
+    boolean mayHaveMoreCellsInRow) {
     this.cells = cells;
     this.exists = exists;
     this.stale = stale;
@@ -212,6 +216,10 @@ public Cell[] rawCells() {
     return cells;
   }
 
+  ExtendedCell[] rawExtendedCells() {
+    return cells;
+  }
+
   /**
    * Create a sorted list of the Cell's in this result. Since HBase 0.20.5 this is equivalent to
    * raw().
@@ -263,7 +271,7 @@ private byte[] notNullBytes(final byte[] bytes) {
     }
   }
 
-  protected int binarySearch(final Cell[] kvs, final byte[] family, final byte[] qualifier) {
+  private int binarySearch(final Cell[] kvs, final byte[] family, final byte[] qualifier) {
     byte[] familyNotNull = notNullBytes(family);
     byte[] qualifierNotNull = notNullBytes(qualifier);
     Cell searchTerm = PrivateCellUtil.createFirstOnRow(kvs[0].getRowArray(), kvs[0].getRowOffset(),
@@ -294,7 +302,7 @@ protected int binarySearch(final Cell[] kvs, final byte[] family, final byte[] q
    * @param qlength   qualifier length
    * @return the index where the value was found, or -1 otherwise
    */
-  protected int binarySearch(final Cell[] kvs, final byte[] family, final int foffset,
+  private int binarySearch(final Cell[] kvs, final byte[] family, final int foffset,
     final int flength, final byte[] qualifier, final int qoffset, final int qlength) {
 
     double keyValueSize =
@@ -734,12 +742,12 @@ public static void compareResults(Result res1, Result res2, boolean verbose) thr
             + ", " + res1.size() + " cells are compared to " + res2.size() + " cells");
       }
     }
-    Cell[] ourKVs = res1.rawCells();
-    Cell[] replicatedKVs = res2.rawCells();
+    ExtendedCell[] ourKVs = res1.cells;
+    ExtendedCell[] replicatedKVs = res2.cells;
     for (int i = 0; i < res1.size(); i++) {
       if (
         !ourKVs[i].equals(replicatedKVs[i]) || !CellUtil.matchingValue(ourKVs[i], replicatedKVs[i])
-          || !CellUtil.matchingTags(ourKVs[i], replicatedKVs[i])
+          || !PrivateCellUtil.matchingTags(ourKVs[i], replicatedKVs[i])
       ) {
         if (verbose) {
           throw new Exception("This result was different: " + res1 + " compared to " + res2);
@@ -824,18 +832,29 @@ public void copyFrom(Result other) {
     this.cells = other.cells;
   }
 
+  /**
+   * For client users: You should only use the return value as a
+   * {@link org.apache.hadoop.hbase.CellScanner}, {@link ExtendedCellScanner} is marked as
+   * IA.Private which means there is no guarantee about its API stability.
+   */
   @Override
-  public CellScanner cellScanner() {
+  public ExtendedCellScanner cellScanner() {
     // Reset
     this.cellScannerIndex = INITIAL_CELLSCANNER_INDEX;
     return this;
   }
 
+  /**
+   * For client users: You should only use the return value as a {@link Cell}, {@link ExtendedCell}
+   * is marked as IA.Private which means there is no guarantee about its API stability.
+   */
   @Override
-  public Cell current() {
+  public ExtendedCell current() {
     if (
       isEmpty() || cellScannerIndex == INITIAL_CELLSCANNER_INDEX || cellScannerIndex >= cells.length
-    ) return null;
+    ) {
+      return null;
+    }
     return this.cells[cellScannerIndex];
   }
 
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/Call.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/Call.java
index 980e708d235c..45a9b29daba2 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/Call.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/Call.java
@@ -22,7 +22,7 @@
 import java.util.Map;
 import org.apache.commons.lang3.builder.ToStringBuilder;
 import org.apache.commons.lang3.builder.ToStringStyle;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.client.MetricsConnection;
 import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
 import org.apache.yetus.audience.InterfaceAudience;
@@ -44,7 +44,7 @@ class Call {
    * Optionally has cells when making call. Optionally has cells set on response. Used passing cells
    * to the rpc and receiving the response.
    */
-  CellScanner cells;
+  ExtendedCellScanner cells;
   @edu.umd.cs.findbugs.annotations.SuppressWarnings(value = "IS2_INCONSISTENT_SYNC",
       justification = "Direct access is only allowed after done")
   Message response; // value, null if error
@@ -63,9 +63,10 @@ class Call {
   final Span span;
   Timeout timeoutTask;
 
-  Call(int id, final Descriptors.MethodDescriptor md, Message param, final CellScanner cells,
-    final Message responseDefaultType, int timeout, int priority, Map<String, byte[]> attributes,
-    RpcCallback<Call> callback, MetricsConnection.CallStats callStats) {
+  Call(int id, final Descriptors.MethodDescriptor md, Message param,
+    final ExtendedCellScanner cells, final Message responseDefaultType, int timeout, int priority,
+    Map<String, byte[]> attributes, RpcCallback<Call> callback,
+    MetricsConnection.CallStats callStats) {
     this.param = param;
     this.md = md;
     this.cells = cells;
@@ -136,7 +137,7 @@ public void setException(IOException error) {
    * @param response return value of the call.
    * @param cells    Can be null
    */
-  public void setResponse(Message response, final CellScanner cells) {
+  public void setResponse(Message response, final ExtendedCellScanner cells) {
     synchronized (this) {
       if (done) {
         return;
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/CellBlockBuilder.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/CellBlockBuilder.java
index e7364ca3b429..a52aa8693f68 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/CellBlockBuilder.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/CellBlockBuilder.java
@@ -26,8 +26,8 @@
 import org.apache.commons.io.IOUtils;
 import org.apache.hadoop.conf.Configurable;
 import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.hbase.CellScanner;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.codec.Codec;
 import org.apache.hadoop.hbase.io.ByteBuffAllocator;
 import org.apache.hadoop.hbase.io.ByteBuffInputStream;
@@ -110,7 +110,7 @@ public int size() {
    *         been flipped and is ready for reading. Use limit to find total size.
    */
   public ByteBuffer buildCellBlock(final Codec codec, final CompressionCodec compressor,
-    final CellScanner cellScanner) throws IOException {
+    final ExtendedCellScanner cellScanner) throws IOException {
     ByteBufferOutputStreamSupplier supplier = new ByteBufferOutputStreamSupplier();
     if (buildCellBlock(codec, compressor, cellScanner, supplier)) {
       ByteBuffer bb = supplier.baos.getByteBuffer();
@@ -144,8 +144,8 @@ public int size() {
     }
   }
 
-  public ByteBuf buildCellBlock(Codec codec, CompressionCodec compressor, CellScanner cellScanner,
-    ByteBufAllocator alloc) throws IOException {
+  public ByteBuf buildCellBlock(Codec codec, CompressionCodec compressor,
+    ExtendedCellScanner cellScanner, ByteBufAllocator alloc) throws IOException {
     ByteBufOutputStreamSupplier supplier = new ByteBufOutputStreamSupplier(alloc);
     if (buildCellBlock(codec, compressor, cellScanner, supplier)) {
       return supplier.buf;
@@ -155,7 +155,7 @@ public ByteBuf buildCellBlock(Codec codec, CompressionCodec compressor, CellScan
   }
 
   private boolean buildCellBlock(final Codec codec, final CompressionCodec compressor,
-    final CellScanner cellScanner, OutputStreamSupplier supplier) throws IOException {
+    final ExtendedCellScanner cellScanner, OutputStreamSupplier supplier) throws IOException {
     if (cellScanner == null) {
       return false;
     }
@@ -171,7 +171,7 @@ private boolean buildCellBlock(final Codec codec, final CompressionCodec compres
     return true;
   }
 
-  private void encodeCellsTo(OutputStream os, CellScanner cellScanner, Codec codec,
+  private void encodeCellsTo(OutputStream os, ExtendedCellScanner cellScanner, Codec codec,
     CompressionCodec compressor) throws IOException {
     Compressor poolCompressor = null;
     try {
@@ -212,7 +212,7 @@ private void encodeCellsTo(OutputStream os, CellScanner cellScanner, Codec codec
    * @throws IOException if encoding the cells fail
    */
   public ByteBufferListOutputStream buildCellBlockStream(Codec codec, CompressionCodec compressor,
-    CellScanner cellScanner, ByteBuffAllocator allocator) throws IOException {
+    ExtendedCellScanner cellScanner, ByteBuffAllocator allocator) throws IOException {
     if (cellScanner == null) {
       return null;
     }
@@ -235,7 +235,7 @@ public ByteBufferListOutputStream buildCellBlockStream(Codec codec, CompressionC
    * @return CellScanner to work against the content of <code>cellBlock</code>
    * @throws IOException if encoding fails
    */
-  public CellScanner createCellScanner(final Codec codec, final CompressionCodec compressor,
+  public ExtendedCellScanner createCellScanner(final Codec codec, final CompressionCodec compressor,
     final byte[] cellBlock) throws IOException {
     // Use this method from Client side to create the CellScanner
     if (compressor != null) {
@@ -258,7 +258,7 @@ public CellScanner createCellScanner(final Codec codec, final CompressionCodec c
    *         out of the CellScanner will share the same ByteBuffer being passed.
    * @throws IOException if cell encoding fails
    */
-  public CellScanner createCellScannerReusingBuffers(final Codec codec,
+  public ExtendedCellScanner createCellScannerReusingBuffers(final Codec codec,
     final CompressionCodec compressor, ByteBuff cellBlock) throws IOException {
     // Use this method from HRS to create the CellScanner
     // If compressed, decompress it first before passing it on else we will leak compression
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/DelegatingHBaseRpcController.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/DelegatingHBaseRpcController.java
index 2b8839bf8462..5b220a24ec56 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/DelegatingHBaseRpcController.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/DelegatingHBaseRpcController.java
@@ -19,7 +19,7 @@
 
 import java.io.IOException;
 import java.util.Map;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.TableName;
 import org.apache.yetus.audience.InterfaceAudience;
 
@@ -74,12 +74,12 @@ public void notifyOnCancel(RpcCallback<Object> callback) {
   }
 
   @Override
-  public CellScanner cellScanner() {
+  public ExtendedCellScanner cellScanner() {
     return delegate.cellScanner();
   }
 
   @Override
-  public void setCellScanner(CellScanner cellScanner) {
+  public void setCellScanner(ExtendedCellScanner cellScanner) {
     delegate.setCellScanner(cellScanner);
   }
 
@@ -134,7 +134,7 @@ public IOException getFailed() {
   }
 
   @Override
-  public void setDone(CellScanner cellScanner) {
+  public void setDone(ExtendedCellScanner cellScanner) {
     delegate.setDone(cellScanner);
   }
 
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/HBaseRpcController.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/HBaseRpcController.java
index 4d3e038bb5ec..8fe44ca59cfc 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/HBaseRpcController.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/HBaseRpcController.java
@@ -19,8 +19,8 @@
 
 import java.io.IOException;
 import java.util.Map;
-import org.apache.hadoop.hbase.CellScannable;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCellScannable;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.TableName;
@@ -42,13 +42,13 @@
 @InterfaceAudience.LimitedPrivate({ HBaseInterfaceAudience.COPROC, HBaseInterfaceAudience.PHOENIX,
   HBaseInterfaceAudience.REPLICATION })
 @InterfaceStability.Evolving
-public interface HBaseRpcController extends RpcController, CellScannable {
+public interface HBaseRpcController extends RpcController, ExtendedCellScannable {
 
   /**
    * Only used to send cells to rpc server, the returned cells should be set by
-   * {@link #setDone(CellScanner)}.
+   * {@link #setDone(ExtendedCellScanner)}.
    */
-  void setCellScanner(CellScanner cellScanner);
+  void setCellScanner(ExtendedCellScanner cellScanner);
 
   /**
    * Set the priority for this operation.
@@ -97,7 +97,7 @@ public interface HBaseRpcController extends RpcController, CellScannable {
    * <b>IMPORTANT:</b> always call this method if the call finished without any exception to tell
    * the {@code HBaseRpcController} that we are done.
    */
-  void setDone(CellScanner cellScanner);
+  void setDone(ExtendedCellScanner cellScanner);
 
   /**
    * A little different from the basic RpcController:
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/HBaseRpcControllerImpl.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/HBaseRpcControllerImpl.java
index 54e9310b5ae7..0667ce2ee627 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/HBaseRpcControllerImpl.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/HBaseRpcControllerImpl.java
@@ -22,10 +22,10 @@
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
-import org.apache.hadoop.hbase.CellScannable;
-import org.apache.hadoop.hbase.CellScanner;
-import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.ExtendedCellScannable;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HConstants;
+import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.TableName;
 import org.apache.hadoop.hbase.client.RegionInfo;
 import org.apache.yetus.audience.InterfaceAudience;
@@ -72,28 +72,29 @@ public class HBaseRpcControllerImpl implements HBaseRpcController {
    * sometimes the scanner is backed by a List of Cells and other times, it is backed by an encoded
    * block that implements CellScanner.
    */
-  private CellScanner cellScanner;
+  private ExtendedCellScanner cellScanner;
 
   private Map<String, byte[]> requestAttributes = Collections.emptyMap();
 
   public HBaseRpcControllerImpl() {
-    this(null, (CellScanner) null);
+    this(null, (ExtendedCellScanner) null);
   }
 
   /**
    * Used server-side. Clients should go via {@link RpcControllerFactory}
    */
-  public HBaseRpcControllerImpl(final CellScanner cellScanner) {
+  public HBaseRpcControllerImpl(final ExtendedCellScanner cellScanner) {
     this(null, cellScanner);
   }
 
-  HBaseRpcControllerImpl(RegionInfo regionInfo, final CellScanner cellScanner) {
+  HBaseRpcControllerImpl(RegionInfo regionInfo, final ExtendedCellScanner cellScanner) {
     this.cellScanner = cellScanner;
     this.regionInfo = regionInfo;
   }
 
-  HBaseRpcControllerImpl(RegionInfo regionInfo, final List<CellScannable> cellIterables) {
-    this.cellScanner = cellIterables == null ? null : CellUtil.createCellScanner(cellIterables);
+  HBaseRpcControllerImpl(RegionInfo regionInfo, final List<ExtendedCellScannable> cellIterables) {
+    this.cellScanner =
+      cellIterables == null ? null : PrivateCellUtil.createExtendedCellScanner(cellIterables);
     this.regionInfo = null;
   }
 
@@ -109,14 +110,14 @@ public RegionInfo getRegionInfo() {
 
   /** Returns One-shot cell scanner (you cannot back it up and restart) */
   @Override
-  public CellScanner cellScanner() {
+  public ExtendedCellScanner cellScanner() {
     return cellScanner;
   }
 
   @edu.umd.cs.findbugs.annotations.SuppressWarnings(value = "IS2_INCONSISTENT_SYNC",
       justification = "The only possible race method is startCancel")
   @Override
-  public void setCellScanner(final CellScanner cellScanner) {
+  public void setCellScanner(final ExtendedCellScanner cellScanner) {
     this.cellScanner = cellScanner;
   }
 
@@ -240,7 +241,7 @@ public synchronized IOException getFailed() {
   }
 
   @Override
-  public synchronized void setDone(CellScanner cellScanner) {
+  public synchronized void setDone(ExtendedCellScanner cellScanner) {
     if (done) {
       return;
     }
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/RpcConnection.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/RpcConnection.java
index 8017e99ec4ff..dbdb0e2037f8 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/RpcConnection.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/RpcConnection.java
@@ -34,7 +34,7 @@
 import java.util.function.Consumer;
 import javax.security.sasl.SaslException;
 import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.client.MetricsConnection;
 import org.apache.hadoop.hbase.codec.Codec;
@@ -382,7 +382,7 @@ private <T extends InputStream & DataInput> void finishCall(ResponseHeader respo
     } else {
       value = null;
     }
-    CellScanner cellBlockScanner;
+    ExtendedCellScanner cellBlockScanner;
     if (responseHeader.hasCellBlockMeta()) {
       int size = responseHeader.getCellBlockMeta().getLength();
       // Maybe we could read directly from the ByteBuf.
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/RpcControllerFactory.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/RpcControllerFactory.java
index a256769de703..1977f09abb11 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/RpcControllerFactory.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/RpcControllerFactory.java
@@ -19,8 +19,8 @@
 
 import java.util.List;
 import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.hbase.CellScannable;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCellScannable;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.hadoop.hbase.client.RegionInfo;
 import org.apache.hadoop.hbase.util.ReflectionUtils;
@@ -54,20 +54,20 @@ public HBaseRpcController newController() {
     return new HBaseRpcControllerImpl();
   }
 
-  public HBaseRpcController newController(CellScanner cellScanner) {
+  public HBaseRpcController newController(ExtendedCellScanner cellScanner) {
     return new HBaseRpcControllerImpl(null, cellScanner);
   }
 
-  public HBaseRpcController newController(RegionInfo regionInfo, CellScanner cellScanner) {
+  public HBaseRpcController newController(RegionInfo regionInfo, ExtendedCellScanner cellScanner) {
     return new HBaseRpcControllerImpl(regionInfo, cellScanner);
   }
 
-  public HBaseRpcController newController(final List<CellScannable> cellIterables) {
+  public HBaseRpcController newController(final List<ExtendedCellScannable> cellIterables) {
     return new HBaseRpcControllerImpl(null, cellIterables);
   }
 
   public HBaseRpcController newController(RegionInfo regionInfo,
-    final List<CellScannable> cellIterables) {
+    final List<ExtendedCellScannable> cellIterables) {
     return new HBaseRpcControllerImpl(regionInfo, cellIterables);
   }
 
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/shaded/protobuf/ProtobufUtil.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/shaded/protobuf/ProtobufUtil.java
index d48b8b73a316..d3672c5e841b 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/shaded/protobuf/ProtobufUtil.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/shaded/protobuf/ProtobufUtil.java
@@ -57,6 +57,7 @@
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.CompareOperator;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.ExtendedCellBuilder;
 import org.apache.hadoop.hbase.ExtendedCellBuilderFactory;
 import org.apache.hadoop.hbase.HBaseConfiguration;
@@ -245,7 +246,7 @@ private ProtobufUtil() {
    * Many results are simple: no cell, exists true or false. To save on object creations, we reuse
    * them across calls.
    */
-  private final static Cell[] EMPTY_CELL_ARRAY = new Cell[] {};
+  private final static ExtendedCell[] EMPTY_CELL_ARRAY = new ExtendedCell[0];
   private final static Result EMPTY_RESULT = Result.create(EMPTY_CELL_ARRAY);
   final static Result EMPTY_RESULT_EXISTS_TRUE = Result.create(null, true);
   final static Result EMPTY_RESULT_EXISTS_FALSE = Result.create(null, false);
@@ -2024,7 +2025,7 @@ private static ByteString wrap(ByteBuffer b, int offset, int length) {
     return UnsafeByteOperations.unsafeWrap(dup);
   }
 
-  public static Cell toCell(ExtendedCellBuilder cellBuilder, final CellProtos.Cell cell,
+  public static ExtendedCell toCell(ExtendedCellBuilder cellBuilder, final CellProtos.Cell cell,
     boolean decodeTags) {
     ExtendedCellBuilder builder = cellBuilder.clear().setRow(cell.getRow().toByteArray())
       .setFamily(cell.getFamily().toByteArray()).setQualifier(cell.getQualifier().toByteArray())
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/shaded/protobuf/RequestConverter.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/shaded/protobuf/RequestConverter.java
index ce12aaea0d24..b98094ad92a6 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/shaded/protobuf/RequestConverter.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/shaded/protobuf/RequestConverter.java
@@ -27,11 +27,11 @@
 import java.util.regex.Pattern;
 import java.util.stream.Collectors;
 import org.apache.commons.lang3.StringUtils;
-import org.apache.hadoop.hbase.CellScannable;
 import org.apache.hadoop.hbase.ClusterMetrics.Option;
 import org.apache.hadoop.hbase.ClusterMetricsBuilder;
 import org.apache.hadoop.hbase.CompareOperator;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
+import org.apache.hadoop.hbase.ExtendedCellScannable;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.NamespaceDescriptor;
 import org.apache.hadoop.hbase.ServerName;
@@ -469,7 +469,7 @@ public static BulkLoadHFileRequest buildBulkLoadHFileRequest(
    *                            RowMutations/CheckAndMutate within the original list of actions
    */
   public static void buildNoDataRegionActions(final byte[] regionName,
-    final Iterable<Action> actions, final List<CellScannable> cells,
+    final Iterable<Action> actions, final List<ExtendedCellScannable> cells,
     final MultiRequest.Builder multiRequestBuilder, final RegionAction.Builder regionActionBuilder,
     final ClientProtos.Action.Builder actionBuilder, final MutationProto.Builder mutationBuilder,
     long nonceGroup, final Map<Integer, Integer> indexMap) throws IOException {
@@ -609,17 +609,19 @@ public static void buildNoDataRegionActions(final byte[] regionName,
     }
   }
 
-  private static void buildNoDataRegionAction(final Put put, final List<CellScannable> cells,
-    final RegionAction.Builder regionActionBuilder, final ClientProtos.Action.Builder actionBuilder,
-    final MutationProto.Builder mutationBuilder) throws IOException {
+  private static void buildNoDataRegionAction(final Put put,
+    final List<ExtendedCellScannable> cells, final RegionAction.Builder regionActionBuilder,
+    final ClientProtos.Action.Builder actionBuilder, final MutationProto.Builder mutationBuilder)
+    throws IOException {
     cells.add(put);
     regionActionBuilder.addAction(actionBuilder
       .setMutation(ProtobufUtil.toMutationNoData(MutationType.PUT, put, mutationBuilder)));
   }
 
-  private static void buildNoDataRegionAction(final Delete delete, final List<CellScannable> cells,
-    final RegionAction.Builder regionActionBuilder, final ClientProtos.Action.Builder actionBuilder,
-    final MutationProto.Builder mutationBuilder) throws IOException {
+  private static void buildNoDataRegionAction(final Delete delete,
+    final List<ExtendedCellScannable> cells, final RegionAction.Builder regionActionBuilder,
+    final ClientProtos.Action.Builder actionBuilder, final MutationProto.Builder mutationBuilder)
+    throws IOException {
     int size = delete.size();
     // Note that a legitimate Delete may have a size of zero; i.e. a Delete that has nothing
     // in it but the row to delete. In this case, the current implementation does not make
@@ -637,18 +639,18 @@ private static void buildNoDataRegionAction(final Delete delete, final List<Cell
   }
 
   private static void buildNoDataRegionAction(final Increment increment,
-    final List<CellScannable> cells, long nonce, final RegionAction.Builder regionActionBuilder,
-    final ClientProtos.Action.Builder actionBuilder, final MutationProto.Builder mutationBuilder)
-    throws IOException {
+    final List<ExtendedCellScannable> cells, long nonce,
+    final RegionAction.Builder regionActionBuilder, final ClientProtos.Action.Builder actionBuilder,
+    final MutationProto.Builder mutationBuilder) throws IOException {
     cells.add(increment);
     regionActionBuilder.addAction(actionBuilder.setMutation(
       ProtobufUtil.toMutationNoData(MutationType.INCREMENT, increment, mutationBuilder, nonce)));
   }
 
-  private static void buildNoDataRegionAction(final Append append, final List<CellScannable> cells,
-    long nonce, final RegionAction.Builder regionActionBuilder,
-    final ClientProtos.Action.Builder actionBuilder, final MutationProto.Builder mutationBuilder)
-    throws IOException {
+  private static void buildNoDataRegionAction(final Append append,
+    final List<ExtendedCellScannable> cells, long nonce,
+    final RegionAction.Builder regionActionBuilder, final ClientProtos.Action.Builder actionBuilder,
+    final MutationProto.Builder mutationBuilder) throws IOException {
     cells.add(append);
     regionActionBuilder.addAction(actionBuilder.setMutation(
       ProtobufUtil.toMutationNoData(MutationType.APPEND, append, mutationBuilder, nonce)));
@@ -656,9 +658,9 @@ private static void buildNoDataRegionAction(final Append append, final List<Cell
 
   /** Returns whether or not the rowMutations has a Increment or Append */
   private static boolean buildNoDataRegionAction(final RowMutations rowMutations,
-    final List<CellScannable> cells, long nonce, final RegionAction.Builder regionActionBuilder,
-    final ClientProtos.Action.Builder actionBuilder, final MutationProto.Builder mutationBuilder)
-    throws IOException {
+    final List<ExtendedCellScannable> cells, long nonce,
+    final RegionAction.Builder regionActionBuilder, final ClientProtos.Action.Builder actionBuilder,
+    final MutationProto.Builder mutationBuilder) throws IOException {
     boolean ret = false;
     for (Mutation mutation : rowMutations.getMutations()) {
       mutationBuilder.clear();
diff --git a/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestMutation.java b/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestMutation.java
index 718ca05b92f3..5da59b144a5f 100644
--- a/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestMutation.java
+++ b/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestMutation.java
@@ -26,7 +26,9 @@
 import org.apache.hadoop.hbase.CellBuilderFactory;
 import org.apache.hadoop.hbase.CellBuilderType;
 import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
+import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.io.TimeRange;
 import org.apache.hadoop.hbase.testclassification.ClientTests;
 import org.apache.hadoop.hbase.testclassification.SmallTests;
@@ -124,13 +126,13 @@ public void testPutCopyConstructor() throws IOException {
   private void assertEquals(Mutation origin, Mutation clone) {
     Assert.assertEquals(origin.getFamilyCellMap().size(), clone.getFamilyCellMap().size());
     for (byte[] family : origin.getFamilyCellMap().keySet()) {
-      List<Cell> originCells = origin.getCellList(family);
-      List<Cell> cloneCells = clone.getCellList(family);
+      List<ExtendedCell> originCells = origin.getCellList(family);
+      List<ExtendedCell> cloneCells = clone.getCellList(family);
       Assert.assertEquals(originCells.size(), cloneCells.size());
       for (int i = 0; i != cloneCells.size(); ++i) {
-        Cell originCell = originCells.get(i);
-        Cell cloneCell = cloneCells.get(i);
-        assertTrue(CellUtil.equals(originCell, cloneCell));
+        ExtendedCell originCell = originCells.get(i);
+        ExtendedCell cloneCell = cloneCells.get(i);
+        assertTrue(PrivateCellUtil.equals(originCell, cloneCell));
         assertTrue(CellUtil.matchingValue(originCell, cloneCell));
       }
     }
diff --git a/hbase-client/src/test/java/org/apache/hadoop/hbase/ipc/TestCellBlockBuilder.java b/hbase-client/src/test/java/org/apache/hadoop/hbase/ipc/TestCellBlockBuilder.java
index fccea923635a..c3a145ea6f33 100644
--- a/hbase-client/src/test/java/org/apache/hadoop/hbase/ipc/TestCellBlockBuilder.java
+++ b/hbase-client/src/test/java/org/apache/hadoop/hbase/ipc/TestCellBlockBuilder.java
@@ -21,18 +21,17 @@
 
 import java.io.IOException;
 import java.nio.ByteBuffer;
-import java.util.Arrays;
 import org.apache.commons.lang3.time.StopWatch;
 import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.CellScanner;
-import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.ExtendedCell;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.codec.Codec;
 import org.apache.hadoop.hbase.codec.KeyValueCodec;
-import org.apache.hadoop.hbase.io.SizedCellScanner;
+import org.apache.hadoop.hbase.io.SizedExtendedCellScanner;
 import org.apache.hadoop.hbase.nio.SingleByteBuff;
 import org.apache.hadoop.hbase.testclassification.ClientTests;
 import org.apache.hadoop.hbase.testclassification.SmallTests;
@@ -78,10 +77,9 @@ static void doBuildCellBlockUndoCellBlock(final CellBlockBuilder builder, final
   static void doBuildCellBlockUndoCellBlock(final CellBlockBuilder builder, final Codec codec,
     final CompressionCodec compressor, final int count, final int size, final boolean sized)
     throws IOException {
-    Cell[] cells = getCells(count, size);
-    CellScanner cellScanner = sized
-      ? getSizedCellScanner(cells)
-      : CellUtil.createCellScanner(Arrays.asList(cells).iterator());
+    ExtendedCell[] cells = getCells(count, size);
+    ExtendedCellScanner cellScanner =
+      sized ? getSizedCellScanner(cells) : PrivateCellUtil.createExtendedCellScanner(cells);
     ByteBuffer bb = builder.buildCellBlock(codec, compressor, cellScanner);
     cellScanner =
       builder.createCellScannerReusingBuffers(codec, compressor, new SingleByteBuff(bb));
@@ -92,21 +90,21 @@ static void doBuildCellBlockUndoCellBlock(final CellBlockBuilder builder, final
     assertEquals(count, i);
   }
 
-  static CellScanner getSizedCellScanner(final Cell[] cells) {
+  static ExtendedCellScanner getSizedCellScanner(final ExtendedCell[] cells) {
     int size = -1;
     for (Cell cell : cells) {
       size += PrivateCellUtil.estimatedSerializedSizeOf(cell);
     }
     final int totalSize = ClassSize.align(size);
-    final CellScanner cellScanner = CellUtil.createCellScanner(cells);
-    return new SizedCellScanner() {
+    final ExtendedCellScanner cellScanner = PrivateCellUtil.createExtendedCellScanner(cells);
+    return new SizedExtendedCellScanner() {
       @Override
       public long heapSize() {
         return totalSize;
       }
 
       @Override
-      public Cell current() {
+      public ExtendedCell current() {
         return cellScanner.current();
       }
 
@@ -117,12 +115,12 @@ public boolean advance() throws IOException {
     };
   }
 
-  static Cell[] getCells(final int howMany) {
+  static ExtendedCell[] getCells(final int howMany) {
     return getCells(howMany, 1024);
   }
 
-  static Cell[] getCells(final int howMany, final int valueSize) {
-    Cell[] cells = new Cell[howMany];
+  static ExtendedCell[] getCells(final int howMany, final int valueSize) {
+    ExtendedCell[] cells = new ExtendedCell[howMany];
     byte[] value = new byte[valueSize];
     for (int i = 0; i < howMany; i++) {
       byte[] index = Bytes.toBytes(i);
diff --git a/hbase-client/src/test/java/org/apache/hadoop/hbase/ipc/TestHBaseRpcControllerImpl.java b/hbase-client/src/test/java/org/apache/hadoop/hbase/ipc/TestHBaseRpcControllerImpl.java
index a0b68646b145..a1ef458b3b48 100644
--- a/hbase-client/src/test/java/org/apache/hadoop/hbase/ipc/TestHBaseRpcControllerImpl.java
+++ b/hbase-client/src/test/java/org/apache/hadoop/hbase/ipc/TestHBaseRpcControllerImpl.java
@@ -24,8 +24,10 @@
 import java.util.ArrayList;
 import java.util.List;
 import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.CellScannable;
 import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCell;
+import org.apache.hadoop.hbase.ExtendedCellScannable;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.testclassification.ClientTests;
 import org.apache.hadoop.hbase.testclassification.SmallTests;
@@ -43,7 +45,7 @@ public class TestHBaseRpcControllerImpl {
   @Test
   public void testListOfCellScannerables() throws IOException {
     final int count = 10;
-    List<CellScannable> cells = new ArrayList<>(count);
+    List<ExtendedCellScannable> cells = new ArrayList<>(count);
 
     for (int i = 0; i < count; i++) {
       cells.add(createCell(i));
@@ -64,16 +66,16 @@ public void testListOfCellScannerables() throws IOException {
    * @param index the index of the cell to use as its value
    * @return A faked out 'Cell' that does nothing but return index as its value
    */
-  static CellScannable createCell(final int index) {
-    return new CellScannable() {
+  static ExtendedCellScannable createCell(final int index) {
+    return new ExtendedCellScannable() {
       @Override
-      public CellScanner cellScanner() {
-        return new CellScanner() {
+      public ExtendedCellScanner cellScanner() {
+        return new ExtendedCellScanner() {
           @Override
-          public Cell current() {
+          public ExtendedCell current() {
             // Fake out a Cell. All this Cell has is a value that is an int in size and equal
             // to the above 'index' param serialized as an int.
-            return new Cell() {
+            return new ExtendedCell() {
               @Override
               public long heapSize() {
                 return 0;
@@ -180,6 +182,18 @@ public byte[] getTagsArray() {
               public Type getType() {
                 return null;
               }
+
+              @Override
+              public void setSequenceId(long seqId) throws IOException {
+              }
+
+              @Override
+              public void setTimestamp(long ts) throws IOException {
+              }
+
+              @Override
+              public void setTimestamp(byte[] ts) throws IOException {
+              }
             };
           }
 
diff --git a/hbase-client/src/test/java/org/apache/hadoop/hbase/shaded/protobuf/TestProtobufUtil.java b/hbase-client/src/test/java/org/apache/hadoop/hbase/shaded/protobuf/TestProtobufUtil.java
index 2b4380dfbb6d..acc561812853 100644
--- a/hbase-client/src/test/java/org/apache/hadoop/hbase/shaded/protobuf/TestProtobufUtil.java
+++ b/hbase-client/src/test/java/org/apache/hadoop/hbase/shaded/protobuf/TestProtobufUtil.java
@@ -31,6 +31,7 @@
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellBuilderType;
 import org.apache.hadoop.hbase.CellComparatorImpl;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.ExtendedCellBuilder;
 import org.apache.hadoop.hbase.ExtendedCellBuilderFactory;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
@@ -505,7 +506,7 @@ public void testCellConversionWithTags() {
     CellProtos.Cell protoCell = ProtobufUtil.toCell(cell, true);
     assertNotNull(protoCell);
 
-    Cell decodedCell = getCellFromProtoResult(protoCell, true);
+    ExtendedCell decodedCell = getCellFromProtoResult(protoCell, true);
     List<Tag> decodedTags = PrivateCellUtil.getTags(decodedCell);
     assertEquals(1, decodedTags.size());
     Tag decodedTag = decodedTags.get(0);
@@ -525,7 +526,7 @@ private Cell getCellWithTags() {
     return cellBuilder.build();
   }
 
-  private Cell getCellFromProtoResult(CellProtos.Cell protoCell, boolean decodeTags) {
+  private ExtendedCell getCellFromProtoResult(CellProtos.Cell protoCell, boolean decodeTags) {
     ExtendedCellBuilder decodedBuilder =
       ExtendedCellBuilderFactory.create(CellBuilderType.DEEP_COPY);
     return ProtobufUtil.toCell(decodedBuilder, protoCell, decodeTags);
@@ -542,7 +543,7 @@ public void testCellConversionWithoutTags() {
     CellProtos.Cell protoCell = ProtobufUtil.toCell(cell, false);
     assertNotNull(protoCell);
 
-    Cell decodedCell = getCellFromProtoResult(protoCell, false);
+    ExtendedCell decodedCell = getCellFromProtoResult(protoCell, false);
     List<Tag> decodedTags = PrivateCellUtil.getTags(decodedCell);
     assertEquals(0, decodedTags.size());
   }
@@ -558,7 +559,7 @@ public void testTagEncodeFalseDecodeTrue() {
     CellProtos.Cell protoCell = ProtobufUtil.toCell(cell, false);
     assertNotNull(protoCell);
 
-    Cell decodedCell = getCellFromProtoResult(protoCell, true);
+    ExtendedCell decodedCell = getCellFromProtoResult(protoCell, true);
     List<Tag> decodedTags = PrivateCellUtil.getTags(decodedCell);
     assertEquals(0, decodedTags.size());
   }
@@ -574,7 +575,7 @@ public void testTagEncodeTrueDecodeFalse() {
     CellProtos.Cell protoCell = ProtobufUtil.toCell(cell, true);
     assertNotNull(protoCell);
 
-    Cell decodedCell = getCellFromProtoResult(protoCell, false);
+    ExtendedCell decodedCell = getCellFromProtoResult(protoCell, false);
     List<Tag> decodedTags = PrivateCellUtil.getTags(decodedCell);
     assertEquals(0, decodedTags.size());
   }
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/ByteBufferKeyValue.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/ByteBufferKeyValue.java
index 749f6b46782c..45e6f2d11d45 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/ByteBufferKeyValue.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/ByteBufferKeyValue.java
@@ -328,10 +328,10 @@ public ExtendedCell deepClone() {
    */
   @Override
   public boolean equals(Object other) {
-    if (!(other instanceof Cell)) {
+    if (!(other instanceof ExtendedCell)) {
       return false;
     }
-    return CellUtil.equals(this, (Cell) other);
+    return PrivateCellUtil.equals(this, (ExtendedCell) other);
   }
 
   /**
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/CellComparatorImpl.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/CellComparatorImpl.java
index a94c3679f478..0cd0905cc3a6 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/CellComparatorImpl.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/CellComparatorImpl.java
@@ -761,7 +761,7 @@ public int compareTimestamps(final long ltimestamp, final long rtimestamp) {
   }
 
   @Override
-  public Comparator getSimpleComparator() {
+  public Comparator<Cell> getSimpleComparator() {
     return this;
   }
 
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/CellUtil.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/CellUtil.java
index 85f23550efc7..10213b143632 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/CellUtil.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/CellUtil.java
@@ -309,10 +309,14 @@ public Cell current() {
       public boolean advance() throws IOException {
         while (true) {
           if (this.cellScanner == null) {
-            if (!this.iterator.hasNext()) return false;
+            if (!this.iterator.hasNext()) {
+              return false;
+            }
             this.cellScanner = this.iterator.next().cellScanner();
           }
-          if (this.cellScanner.advance()) return true;
+          if (this.cellScanner.advance()) {
+            return true;
+          }
           this.cellScanner = null;
         }
       }
@@ -357,13 +361,17 @@ public static CellScanner createCellScanner(final Cell[] cellArray) {
 
       @Override
       public Cell current() {
-        if (cells == null) return null;
+        if (cells == null) {
+          return null;
+        }
         return (index < 0) ? null : this.cells[index];
       }
 
       @Override
       public boolean advance() {
-        if (cells == null) return false;
+        if (cells == null) {
+          return false;
+        }
         return ++index < this.cells.length;
       }
     };
@@ -549,8 +557,13 @@ public static boolean matchingValue(final Cell left, final byte[] buf) {
       buf.length);
   }
 
+  /**
+   * @deprecated Since 3.0.0, will be removed in 4.0.0. Tags are now internal only, you should not
+   *             try to check it through the {@link Cell} interface.
+   */
+  @Deprecated
   public static boolean matchingTags(final Cell left, final Cell right) {
-    return PrivateCellUtil.matchingTags(left, right, left.getTagsLength(), right.getTagsLength());
+    return PrivateCellUtil.matchingTags((ExtendedCell) left, (ExtendedCell) right);
   }
 
   /**
@@ -662,7 +675,7 @@ public static String toString(Cell cell, boolean verbose) {
 
   public static boolean equals(Cell a, Cell b) {
     return matchingRows(a, b) && matchingFamily(a, b) && matchingQualifier(a, b)
-      && matchingTimestamp(a, b) && PrivateCellUtil.matchingType(a, b);
+      && matchingTimestamp(a, b) && a.getTypeByte() == b.getTypeByte();
   }
 
   public static boolean matchingTimestamp(Cell a, Cell b) {
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/ExtendedCellScannable.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/ExtendedCellScannable.java
new file mode 100644
index 000000000000..c3772f166221
--- /dev/null
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/ExtendedCellScannable.java
@@ -0,0 +1,37 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.hadoop.hbase;
+
+import org.apache.yetus.audience.InterfaceAudience;
+
+/**
+ * We use this class in HBase internally for getting {@link ExtendedCell} directly without casting.
+ * <p>
+ * In general, all {@link Cell}s in HBase should and must be {@link ExtendedCell}.
+ * <p>
+ * See HBASE-28684 and related issues for more details.
+ * @see CellScannable
+ * @see ExtendedCellScanner
+ * @see ExtendedCell
+ */
+@InterfaceAudience.Private
+public interface ExtendedCellScannable extends CellScannable {
+
+  @Override
+  ExtendedCellScanner cellScanner();
+}
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/ExtendedCellScanner.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/ExtendedCellScanner.java
new file mode 100644
index 000000000000..f7011291d9ce
--- /dev/null
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/ExtendedCellScanner.java
@@ -0,0 +1,37 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.hadoop.hbase;
+
+import org.apache.yetus.audience.InterfaceAudience;
+
+/**
+ * We use this class in HBase internally for getting {@link ExtendedCell} directly without casting.
+ * <p>
+ * In general, all {@link Cell}s in HBase should and must be {@link ExtendedCell}.
+ * <p>
+ * See HBASE-28684 and related issues for more details.
+ * @see CellScanner
+ * @see ExtendedCellScannable
+ * @see ExtendedCell
+ */
+@InterfaceAudience.Private
+public interface ExtendedCellScanner extends CellScanner {
+
+  @Override
+  ExtendedCell current();
+}
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/KeyValue.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/KeyValue.java
index 89e91ca80361..a87a5214fadf 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/KeyValue.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/KeyValue.java
@@ -978,10 +978,10 @@ private static byte[] createByteArray(final byte[] row, final int roffset, final
    */
   @Override
   public boolean equals(Object other) {
-    if (!(other instanceof Cell)) {
+    if (!(other instanceof ExtendedCell)) {
       return false;
     }
-    return CellUtil.equals(this, (Cell) other);
+    return PrivateCellUtil.equals(this, (ExtendedCell) other);
   }
 
   /**
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/KeyValueTestUtil.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/KeyValueTestUtil.java
index ed3687e9ed4d..323cae954f06 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/KeyValueTestUtil.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/KeyValueTestUtil.java
@@ -63,9 +63,12 @@ public static boolean containsIgnoreMvccVersion(Collection<? extends Cell> kvCol
     for (Cell kv1 : kvCollection1) {
       boolean found = false;
       for (Cell kv2 : kvCollection2) {
-        if (PrivateCellUtil.equalsIgnoreMvccVersion(kv1, kv2)) found = true;
+        if (PrivateCellUtil.equalsIgnoreMvccVersion((ExtendedCell) kv1, (ExtendedCell) kv2))
+          found = true;
+      }
+      if (!found) {
+        return false;
       }
-      if (!found) return false;
     }
     return true;
   }
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/KeyValueUtil.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/KeyValueUtil.java
index 4b61688abc28..6c8f2e6e4edb 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/KeyValueUtil.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/KeyValueUtil.java
@@ -88,7 +88,7 @@ public static int totalLengthWithMvccVersion(final Iterable<? extends KeyValue>
 
   /**************** copy the cell to create a new keyvalue *********************/
 
-  public static KeyValue copyToNewKeyValue(final Cell cell) {
+  public static KeyValue copyToNewKeyValue(final ExtendedCell cell) {
     byte[] bytes = copyToNewByteArray(cell);
     KeyValue kvCell = new KeyValue(bytes, 0, bytes.length);
     kvCell.setSequenceId(cell.getSequenceId());
@@ -120,7 +120,7 @@ public static KeyValue toNewKeyCell(final ExtendedCell cell) {
     return kv;
   }
 
-  public static byte[] copyToNewByteArray(final Cell cell) {
+  public static byte[] copyToNewByteArray(final ExtendedCell cell) {
     // Cell#getSerializedSize returns the serialized size of the Source cell, which may
     // not serialize all fields. We are constructing a KeyValue backing array here,
     // which does include all fields, and must allocate accordingly.
@@ -133,7 +133,7 @@ public static byte[] copyToNewByteArray(final Cell cell) {
     return backingBytes;
   }
 
-  public static int appendKeyTo(final Cell cell, final byte[] output, final int offset) {
+  public static int appendKeyTo(final ExtendedCell cell, final byte[] output, final int offset) {
     int nextOffset = offset;
     nextOffset = Bytes.putShort(output, nextOffset, cell.getRowLength());
     nextOffset = CellUtil.copyRowTo(cell, output, nextOffset);
@@ -147,7 +147,8 @@ public static int appendKeyTo(final Cell cell, final byte[] output, final int of
 
   /**************** copy key and value *********************/
 
-  public static int appendToByteArray(Cell cell, byte[] output, int offset, boolean withTags) {
+  public static int appendToByteArray(ExtendedCell cell, byte[] output, int offset,
+    boolean withTags) {
     int pos = offset;
     pos = Bytes.putInt(output, pos, keyLength(cell));
     pos = Bytes.putInt(output, pos, cell.getValueLength());
@@ -416,7 +417,7 @@ public static KeyValue createFirstOnRow(byte[] buffer, final int boffset, final
    * @deprecated without any replacement.
    */
   @Deprecated
-  public static KeyValue ensureKeyValue(final Cell cell) {
+  public static KeyValue ensureKeyValue(final ExtendedCell cell) {
     if (cell == null) return null;
     if (cell instanceof KeyValue) {
       if (cell.getClass().getName().equals(KeyValue.class.getName())) {
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/PrivateCellUtil.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/PrivateCellUtil.java
index 9013f9a9f26c..801e1d423480 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/PrivateCellUtil.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/PrivateCellUtil.java
@@ -29,6 +29,8 @@
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
+import java.util.Map.Entry;
+import java.util.NavigableMap;
 import java.util.Optional;
 import org.apache.hadoop.hbase.filter.ByteArrayComparable;
 import org.apache.hadoop.hbase.io.TagCompressionContext;
@@ -40,6 +42,8 @@
 import org.apache.hadoop.hbase.util.ClassSize;
 import org.apache.yetus.audience.InterfaceAudience;
 
+import org.apache.hbase.thirdparty.com.google.common.base.Preconditions;
+
 /**
  * Utility methods helpful slinging {@link Cell} instances. It has more powerful and rich set of
  * APIs than those in {@link CellUtil} for internal usage.
@@ -72,7 +76,7 @@ public static ByteRange fillValueRange(Cell cell, ByteRange range) {
     return range.set(cell.getValueArray(), cell.getValueOffset(), cell.getValueLength());
   }
 
-  public static ByteRange fillTagRange(Cell cell, ByteRange range) {
+  public static ByteRange fillTagRange(ExtendedCell cell, ByteRange range) {
     return range.set(cell.getTagsArray(), cell.getTagsOffset(), cell.getTagsLength());
   }
 
@@ -582,8 +586,8 @@ public int write(OutputStream out, boolean withTags) throws IOException {
      * Made into a static method so as to reuse the logic within
      * ValueAndTagRewriteByteBufferExtendedCell
      */
-    static int write(OutputStream out, boolean withTags, Cell cell, byte[] value, byte[] tags)
-      throws IOException {
+    static int write(OutputStream out, boolean withTags, ExtendedCell cell, byte[] value,
+      byte[] tags) throws IOException {
       int valLen = value == null ? 0 : value.length;
       ByteBufferUtils.putInt(out, KeyValueUtil.keyLength(cell));// Key length
       ByteBufferUtils.putInt(out, valLen);// Value length
@@ -802,11 +806,16 @@ public static boolean matchingValue(final Cell left, final Cell right, int lvlen
       right.getValueArray(), right.getValueOffset(), rvlength);
   }
 
-  public static boolean matchingType(Cell a, Cell b) {
+  public static boolean matchingType(ExtendedCell a, ExtendedCell b) {
     return a.getTypeByte() == b.getTypeByte();
   }
 
-  public static boolean matchingTags(final Cell left, final Cell right, int llength, int rlength) {
+  public static boolean matchingTags(final ExtendedCell left, final ExtendedCell right) {
+    return matchingTags(left, right, left.getTagsLength(), right.getTagsLength());
+  }
+
+  public static boolean matchingTags(final ExtendedCell left, final ExtendedCell right, int llength,
+    int rlength) {
     if (left instanceof ByteBufferExtendedCell && right instanceof ByteBufferExtendedCell) {
       ByteBufferExtendedCell leftBBCell = (ByteBufferExtendedCell) left;
       ByteBufferExtendedCell rightBBCell = (ByteBufferExtendedCell) right;
@@ -840,7 +849,7 @@ public static boolean isDeleteType(ExtendedCell cell) {
     return cell.getTypeByte() == KeyValue.Type.Delete.getCode();
   }
 
-  public static boolean isDeleteFamily(final Cell cell) {
+  public static boolean isDeleteFamily(final ExtendedCell cell) {
     return cell.getTypeByte() == KeyValue.Type.DeleteFamily.getCode();
   }
 
@@ -862,14 +871,14 @@ public static boolean isDeleteColumnOrFamily(ExtendedCell cell) {
     return t == KeyValue.Type.DeleteColumn.getCode() || t == KeyValue.Type.DeleteFamily.getCode();
   }
 
-  public static byte[] cloneTags(Cell cell) {
+  public static byte[] cloneTags(ExtendedCell cell) {
     byte[] output = new byte[cell.getTagsLength()];
     copyTagsTo(cell, output, 0);
     return output;
   }
 
   /** Copies the tags info into the tag portion of the cell */
-  public static int copyTagsTo(Cell cell, byte[] destination, int destinationOffset) {
+  public static int copyTagsTo(ExtendedCell cell, byte[] destination, int destinationOffset) {
     int tlen = cell.getTagsLength();
     if (cell instanceof ByteBufferExtendedCell) {
       ByteBufferUtils.copyFromBufferToArray(destination,
@@ -883,7 +892,7 @@ public static int copyTagsTo(Cell cell, byte[] destination, int destinationOffse
   }
 
   /** Copies the tags info into the tag portion of the cell */
-  public static int copyTagsTo(Cell cell, ByteBuffer destination, int destinationOffset) {
+  public static int copyTagsTo(ExtendedCell cell, ByteBuffer destination, int destinationOffset) {
     int tlen = cell.getTagsLength();
     if (cell instanceof ByteBufferExtendedCell) {
       ByteBufferUtils.copyFromBufferToBuffer(((ByteBufferExtendedCell) cell).getTagsByteBuffer(),
@@ -900,7 +909,7 @@ public static int copyTagsTo(Cell cell, ByteBuffer destination, int destinationO
    * @param cell The Cell
    * @return Tags in the given Cell as a List
    */
-  public static List<Tag> getTags(Cell cell) {
+  public static List<Tag> getTags(ExtendedCell cell) {
     List<Tag> tags = new ArrayList<>();
     Iterator<Tag> tagsItr = tagsIterator(cell);
     while (tagsItr.hasNext()) {
@@ -915,7 +924,7 @@ public static List<Tag> getTags(Cell cell) {
    * @param type Type of the Tag to retrieve
    * @return Optional, empty if there is no tag of the passed in tag type
    */
-  public static Optional<Tag> getTag(Cell cell, byte type) {
+  public static Optional<Tag> getTag(ExtendedCell cell, byte type) {
     boolean bufferBacked = cell instanceof ByteBufferExtendedCell;
     int length = cell.getTagsLength();
     int offset =
@@ -946,7 +955,7 @@ public static Optional<Tag> getTag(Cell cell, byte type) {
    * @param cell The Cell over which tags iterator is needed.
    * @return iterator for the tags
    */
-  public static Iterator<Tag> tagsIterator(final Cell cell) {
+  public static Iterator<Tag> tagsIterator(final ExtendedCell cell) {
     final int tagsLength = cell.getTagsLength();
     // Save an object allocation where we can
     if (tagsLength == 0) {
@@ -1069,8 +1078,8 @@ public static void writeRowSkippingBytes(DataOutputStream out, Cell cell, short
    * @param withTsType        when true check timestamp and type bytes also.
    * @return length of common prefix
    */
-  public static int findCommonPrefixInFlatKey(Cell c1, Cell c2, boolean bypassFamilyCheck,
-    boolean withTsType) {
+  public static int findCommonPrefixInFlatKey(ExtendedCell c1, ExtendedCell c2,
+    boolean bypassFamilyCheck, boolean withTsType) {
     // Compare the 2 bytes in RK length part
     short rLen1 = c1.getRowLength();
     short rLen2 = c2.getRowLength();
@@ -2196,7 +2205,7 @@ public Type getType() {
    * rk len&gt;&lt;rk&gt;&lt;1 byte cf len&gt;&lt;cf&gt;&lt;qualifier&gt;&lt;8 bytes
    * timestamp&gt;&lt;1 byte type&gt;
    */
-  public static void writeFlatKey(Cell cell, DataOutput out) throws IOException {
+  public static void writeFlatKey(ExtendedCell cell, DataOutput out) throws IOException {
     short rowLen = cell.getRowLength();
     byte fLen = cell.getFamilyLength();
     int qLen = cell.getQualifierLength();
@@ -2223,18 +2232,6 @@ public static void writeFlatKey(Cell cell, DataOutput out) throws IOException {
     out.writeByte(cell.getTypeByte());
   }
 
-  /**
-   * Deep clones the given cell if the cell supports deep cloning
-   * @param cell the cell to be cloned
-   * @return the cloned cell
-   */
-  public static Cell deepClone(Cell cell) throws CloneNotSupportedException {
-    if (cell instanceof ExtendedCell) {
-      return ((ExtendedCell) cell).deepClone();
-    }
-    throw new CloneNotSupportedException();
-  }
-
   /**
    * Writes the cell to the given OutputStream
    * @param cell     the cell to be written
@@ -2242,7 +2239,8 @@ public static Cell deepClone(Cell cell) throws CloneNotSupportedException {
    * @param withTags if tags are to be written or not
    * @return the total bytes written
    */
-  public static int writeCell(Cell cell, OutputStream out, boolean withTags) throws IOException {
+  public static int writeCell(ExtendedCell cell, OutputStream out, boolean withTags)
+    throws IOException {
     if (cell instanceof ExtendedCell) {
       return ((ExtendedCell) cell).write(out, withTags);
     } else {
@@ -2268,23 +2266,7 @@ public static int writeCell(Cell cell, OutputStream out, boolean withTags) throw
     }
   }
 
-  /**
-   * Writes a cell to the buffer at the given offset
-   * @param cell   the cell to be written
-   * @param buf    the buffer to which the cell has to be wrriten
-   * @param offset the offset at which the cell should be written
-   */
-  public static void writeCellToBuffer(Cell cell, ByteBuffer buf, int offset) {
-    if (cell instanceof ExtendedCell) {
-      ((ExtendedCell) cell).write(buf, offset);
-    } else {
-      // Using the KVUtil
-      byte[] bytes = KeyValueUtil.copyToNewByteArray(cell);
-      ByteBufferUtils.copyFromArrayToBuffer(buf, offset, bytes, 0, bytes.length);
-    }
-  }
-
-  public static int writeFlatKey(Cell cell, OutputStream out) throws IOException {
+  public static int writeFlatKey(ExtendedCell cell, OutputStream out) throws IOException {
     short rowLen = cell.getRowLength();
     byte fLen = cell.getFamilyLength();
     int qLen = cell.getQualifierLength();
@@ -2359,9 +2341,9 @@ public static void setTimestamp(Cell cell, byte[] ts) throws IOException {
    * @return True if cell timestamp is modified.
    * @throws IOException when the passed cell is not of type {@link ExtendedCell}
    */
-  public static boolean updateLatestStamp(Cell cell, long ts) throws IOException {
+  public static boolean updateLatestStamp(ExtendedCell cell, long ts) throws IOException {
     if (cell.getTimestamp() == HConstants.LATEST_TIMESTAMP) {
-      setTimestamp(cell, ts);
+      cell.setTimestamp(ts);
       return true;
     }
     return false;
@@ -2452,7 +2434,8 @@ public static void writeQualifierSkippingBytes(DataOutputStream out, Cell cell,
    * @param cell    The cell whose contents has to be written
    * @param vlength the value length
    */
-  public static void writeValue(OutputStream out, Cell cell, int vlength) throws IOException {
+  public static void writeValue(OutputStream out, ExtendedCell cell, int vlength)
+    throws IOException {
     if (cell instanceof ByteBufferExtendedCell) {
       ByteBufferUtils.copyBufferToStream(out, ((ByteBufferExtendedCell) cell).getValueByteBuffer(),
         ((ByteBufferExtendedCell) cell).getValuePosition(), vlength);
@@ -2467,7 +2450,8 @@ public static void writeValue(OutputStream out, Cell cell, int vlength) throws I
    * @param cell       The cell whose contents has to be written
    * @param tagsLength the tag length
    */
-  public static void writeTags(OutputStream out, Cell cell, int tagsLength) throws IOException {
+  public static void writeTags(OutputStream out, ExtendedCell cell, int tagsLength)
+    throws IOException {
     if (cell instanceof ByteBufferExtendedCell) {
       ByteBufferUtils.copyBufferToStream(out, ((ByteBufferExtendedCell) cell).getTagsByteBuffer(),
         ((ByteBufferExtendedCell) cell).getTagsPosition(), tagsLength);
@@ -2479,22 +2463,31 @@ public static void writeTags(OutputStream out, Cell cell, int tagsLength) throws
   /**
    * special case for Cell.equals
    */
-  public static boolean equalsIgnoreMvccVersion(Cell a, Cell b) {
+  public static boolean equalsIgnoreMvccVersion(ExtendedCell a, ExtendedCell b) {
     // row
     boolean res = CellUtil.matchingRows(a, b);
-    if (!res) return res;
+    if (!res) {
+      return res;
+    }
 
     // family
     res = CellUtil.matchingColumn(a, b);
-    if (!res) return res;
+    if (!res) {
+      return res;
+    }
 
     // timestamp: later sorts first
-    if (!CellUtil.matchingTimestamp(a, b)) return false;
+    if (!CellUtil.matchingTimestamp(a, b)) {
+      return false;
+    }
 
     // type
     int c = (0xff & b.getTypeByte()) - (0xff & a.getTypeByte());
-    if (c != 0) return false;
-    else return true;
+    if (c != 0) {
+      return false;
+    } else {
+      return true;
+    }
   }
 
   /**
@@ -2619,8 +2612,8 @@ public static void compressQualifier(OutputStream out, Cell cell, Dictionary dic
    * @return an int greater than 0 if left is greater than right lesser than 0 if left is lesser
    *         than right equal to 0 if left is equal to right
    */
-  public static final int compare(CellComparator comparator, Cell left, byte[] key, int offset,
-    int length) {
+  public static final int compare(CellComparator comparator, ExtendedCell left, byte[] key,
+    int offset, int length) {
     // row
     short rrowlength = Bytes.toShort(key, offset);
     int c = comparator.compareRows(left, key, offset + Bytes.SIZEOF_SHORT, rrowlength);
@@ -2646,7 +2639,7 @@ public static final int compare(CellComparator comparator, Cell left, byte[] key
    * @return greater than 0 if left cell is bigger, less than 0 if right cell is bigger, 0 if both
    *         cells are equal
    */
-  static final int compareWithoutRow(CellComparator comparator, Cell left, byte[] right,
+  static final int compareWithoutRow(CellComparator comparator, ExtendedCell left, byte[] right,
     int roffset, int rlength, short rowlength) {
     /***
      * KeyValue Format and commonLength:
@@ -2954,4 +2947,149 @@ public static ExtendedCell createLastOnRowCol(final Cell cell) {
   public static ExtendedCell createFirstDeleteFamilyCellOnRow(final byte[] row, final byte[] fam) {
     return new FirstOnRowDeleteFamilyCell(row, fam);
   }
+
+  /**
+   * In fact, in HBase, all {@link Cell}s are {@link ExtendedCell}s. We do not expect users to
+   * implement their own {@link Cell} types, except some special projects like Phoenix, where they
+   * just use {@link org.apache.hadoop.hbase.KeyValue} and {@link ExtendedCell} directly.
+   * @return the original {@code cell} which has already been cast to an {@link ExtendedCell}.
+   * @throws IllegalArgumentException if the given {@code cell} is not an {@link ExtendedCell}.
+   */
+  public static ExtendedCell ensureExtendedCell(Cell cell) {
+    Preconditions.checkArgument(cell == null || cell instanceof ExtendedCell,
+      "Unsupported cell type: %s", cell.getClass().getName());
+    return (ExtendedCell) cell;
+  }
+
+  public static boolean equals(ExtendedCell a, ExtendedCell b) {
+    return CellUtil.matchingRows(a, b) && CellUtil.matchingFamily(a, b)
+      && CellUtil.matchingQualifier(a, b) && CellUtil.matchingTimestamp(a, b)
+      && PrivateCellUtil.matchingType(a, b);
+  }
+
+  /** Returns ExtendedCellScanner interface over <code>cellIterables</code> */
+  public static ExtendedCellScanner
+    createExtendedCellScanner(final List<? extends ExtendedCellScannable> cellScannerables) {
+    return new ExtendedCellScanner() {
+      private final Iterator<? extends ExtendedCellScannable> iterator =
+        cellScannerables.iterator();
+      private ExtendedCellScanner cellScanner = null;
+
+      @Override
+      public ExtendedCell current() {
+        return this.cellScanner != null ? this.cellScanner.current() : null;
+      }
+
+      @Override
+      public boolean advance() throws IOException {
+        while (true) {
+          if (this.cellScanner == null) {
+            if (!this.iterator.hasNext()) {
+              return false;
+            }
+            this.cellScanner = this.iterator.next().cellScanner();
+          }
+          if (this.cellScanner.advance()) {
+            return true;
+          }
+          this.cellScanner = null;
+        }
+      }
+    };
+  }
+
+  /**
+   * Flatten the map of cells out under the ExtendedCellScanner
+   * @param map Map of Cell Lists; for example, the map of families to ExtendedCells that is used
+   *            inside Put, etc., keeping Cells organized by family.
+   * @return ExtendedCellScanner interface over <code>cellIterable</code>
+   */
+  public static ExtendedCellScanner
+    createExtendedCellScanner(final NavigableMap<byte[], List<ExtendedCell>> map) {
+    return new ExtendedCellScanner() {
+      private final Iterator<Entry<byte[], List<ExtendedCell>>> entries = map.entrySet().iterator();
+      private Iterator<ExtendedCell> currentIterator = null;
+      private ExtendedCell currentCell;
+
+      @Override
+      public ExtendedCell current() {
+        return this.currentCell;
+      }
+
+      @Override
+      public boolean advance() {
+        while (true) {
+          if (this.currentIterator == null) {
+            if (!this.entries.hasNext()) return false;
+            this.currentIterator = this.entries.next().getValue().iterator();
+          }
+          if (this.currentIterator.hasNext()) {
+            this.currentCell = this.currentIterator.next();
+            return true;
+          }
+          this.currentCell = null;
+          this.currentIterator = null;
+        }
+      }
+    };
+  }
+
+  /** Returns CellScanner interface over <code>cellArray</code> */
+  public static ExtendedCellScanner createExtendedCellScanner(final ExtendedCell[] cellArray) {
+    return new ExtendedCellScanner() {
+      private final ExtendedCell[] cells = cellArray;
+      private int index = -1;
+
+      @Override
+      public ExtendedCell current() {
+        if (cells == null) {
+          return null;
+        }
+        return (index < 0) ? null : this.cells[index];
+      }
+
+      @Override
+      public boolean advance() {
+        if (cells == null) {
+          return false;
+        }
+        return ++index < this.cells.length;
+      }
+    };
+  }
+
+  /** Returns ExtendedCellScanner interface over <code>cellIterable</code> */
+  public static ExtendedCellScanner
+    createExtendedCellScanner(final Iterable<ExtendedCell> cellIterable) {
+    if (cellIterable == null) {
+      return null;
+    }
+    return createExtendedCellScanner(cellIterable.iterator());
+  }
+
+  /**
+   * Returns ExtendedCellScanner interface over <code>cellIterable</code> or null if
+   * <code>cells</code> is null
+   */
+  public static ExtendedCellScanner createExtendedCellScanner(final Iterator<ExtendedCell> cells) {
+    if (cells == null) {
+      return null;
+    }
+    return new ExtendedCellScanner() {
+      private final Iterator<ExtendedCell> iterator = cells;
+      private ExtendedCell current = null;
+
+      @Override
+      public ExtendedCell current() {
+        return this.current;
+      }
+
+      @Override
+      public boolean advance() {
+        boolean hasNext = this.iterator.hasNext();
+        this.current = hasNext ? this.iterator.next() : null;
+        return hasNext;
+      }
+    };
+  }
 }
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/TagUtil.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/TagUtil.java
index 6d911bccd58a..cc15fa7ba752 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/TagUtil.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/TagUtil.java
@@ -66,12 +66,12 @@ public static Pair<Integer, Integer> readVIntValuePart(Tag tag, int offset) thro
   }
 
   /** Returns A List&lt;Tag&gt; of any Tags found in <code>cell</code> else null. */
-  public static List<Tag> carryForwardTags(final Cell cell) {
+  public static List<Tag> carryForwardTags(final ExtendedCell cell) {
     return carryForwardTags(null, cell);
   }
 
   /** Add to <code>tagsOrNull</code> any Tags <code>cell</code> is carrying or null if none. */
-  public static List<Tag> carryForwardTags(final List<Tag> tagsOrNull, final Cell cell) {
+  public static List<Tag> carryForwardTags(final List<Tag> tagsOrNull, final ExtendedCell cell) {
     Iterator<Tag> itr = PrivateCellUtil.tagsIterator(cell);
     if (itr == EMPTY_TAGS_ITR) {
       // If no Tags, return early.
@@ -87,7 +87,7 @@ public static List<Tag> carryForwardTags(final List<Tag> tagsOrNull, final Cell
     return tags;
   }
 
-  public static byte[] concatTags(byte[] tags, Cell cell) {
+  public static byte[] concatTags(byte[] tags, ExtendedCell cell) {
     int cellTagsLen = cell.getTagsLength();
     if (cellTagsLen == 0) {
       // If no Tags, return early.
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/BaseDecoder.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/BaseDecoder.java
index 9a2a29356b14..8f4692ee778f 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/BaseDecoder.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/BaseDecoder.java
@@ -22,21 +22,21 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.PushbackInputStream;
-import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
- * TODO javadoc
+ * Base implementation for {@link Codec.Decoder}.
  */
 @InterfaceAudience.LimitedPrivate({ HBaseInterfaceAudience.COPROC, HBaseInterfaceAudience.PHOENIX })
 public abstract class BaseDecoder implements Codec.Decoder {
   protected static final Logger LOG = LoggerFactory.getLogger(BaseDecoder.class);
 
   protected final InputStream in;
-  private Cell current = null;
+  private ExtendedCell current = null;
 
   protected static class PBIS extends PushbackInputStream {
     public PBIS(InputStream in, int size) {
@@ -98,10 +98,10 @@ protected InputStream getInputStream() {
    *         thrown if EOF is reached prematurely. Does not return null.
    */
   @NonNull
-  protected abstract Cell parseCell() throws IOException;
+  protected abstract ExtendedCell parseCell() throws IOException;
 
   @Override
-  public Cell current() {
+  public ExtendedCell current() {
     return this.current;
   }
 }
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/BaseEncoder.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/BaseEncoder.java
index 3ca5d2462de3..4875fcd227c9 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/BaseEncoder.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/BaseEncoder.java
@@ -19,7 +19,7 @@
 
 import java.io.IOException;
 import java.io.OutputStream;
-import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.yetus.audience.InterfaceAudience;
 
@@ -42,7 +42,7 @@ protected OutputStream getOuputStream() {
   }
 
   @Override
-  public abstract void write(Cell cell) throws IOException;
+  public abstract void write(ExtendedCell cell) throws IOException;
 
   protected void checkFlushed() throws CodecException {
     if (this.flushed) throw new CodecException("Flushed; done");
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/CellCodec.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/CellCodec.java
index f4552c038267..356513be7f75 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/CellCodec.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/CellCodec.java
@@ -21,8 +21,8 @@
 import java.io.InputStream;
 import java.io.OutputStream;
 import org.apache.commons.io.IOUtils;
-import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellBuilderType;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.ExtendedCellBuilder;
 import org.apache.hadoop.hbase.ExtendedCellBuilderFactory;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
@@ -43,7 +43,7 @@ static class CellEncoder extends BaseEncoder {
     }
 
     @Override
-    public void write(Cell cell) throws IOException {
+    public void write(ExtendedCell cell) throws IOException {
       checkFlushed();
       // Row
       write(cell.getRowArray(), cell.getRowOffset(), cell.getRowLength());
@@ -80,7 +80,7 @@ public CellDecoder(final InputStream in) {
     }
 
     @Override
-    protected Cell parseCell() throws IOException {
+    protected ExtendedCell parseCell() throws IOException {
       byte[] row = readByteArray(this.in);
       byte[] family = readByteArray(in);
       byte[] qualifier = readByteArray(in);
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/CellCodecWithTags.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/CellCodecWithTags.java
index 07bfb53d5df7..6a8e7e944439 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/CellCodecWithTags.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/CellCodecWithTags.java
@@ -21,8 +21,8 @@
 import java.io.InputStream;
 import java.io.OutputStream;
 import org.apache.commons.io.IOUtils;
-import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellBuilderType;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.ExtendedCellBuilder;
 import org.apache.hadoop.hbase.ExtendedCellBuilderFactory;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
@@ -44,7 +44,7 @@ static class CellEncoder extends BaseEncoder {
     }
 
     @Override
-    public void write(Cell cell) throws IOException {
+    public void write(ExtendedCell cell) throws IOException {
       checkFlushed();
       // Row
       write(cell.getRowArray(), cell.getRowOffset(), cell.getRowLength());
@@ -82,7 +82,7 @@ public CellDecoder(final InputStream in) {
     }
 
     @Override
-    protected Cell parseCell() throws IOException {
+    protected ExtendedCell parseCell() throws IOException {
       byte[] row = readByteArray(this.in);
       byte[] family = readByteArray(in);
       byte[] qualifier = readByteArray(in);
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/Codec.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/Codec.java
index df8a94f5614b..18c8b8ea0ab8 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/Codec.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/Codec.java
@@ -19,7 +19,7 @@
 
 import java.io.InputStream;
 import java.io.OutputStream;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.hadoop.hbase.io.CellOutputStream;
 import org.apache.hadoop.hbase.nio.ByteBuff;
@@ -46,7 +46,7 @@ interface Encoder extends CellOutputStream {
    * Implementations should implicitly clean up any resources allocated when the Decoder/CellScanner
    * runs off the end of the cell block. Do this rather than require the user call close explicitly.
    */
-  interface Decoder extends CellScanner {
+  interface Decoder extends ExtendedCellScanner {
   }
 
   Decoder getDecoder(InputStream is);
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/KeyValueCodec.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/KeyValueCodec.java
index 9913eac3615c..ef40b395b7b1 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/KeyValueCodec.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/KeyValueCodec.java
@@ -21,7 +21,7 @@
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.nio.ByteBuffer;
-import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.hadoop.hbase.KeyValueUtil;
 import org.apache.hadoop.hbase.NoTagsByteBufferKeyValue;
@@ -55,7 +55,7 @@ public KeyValueEncoder(final OutputStream out) {
     }
 
     @Override
-    public void write(Cell cell) throws IOException {
+    public void write(ExtendedCell cell) throws IOException {
       checkFlushed();
       // Do not write tags over RPC
       ByteBufferUtils.putInt(this.out, KeyValueUtil.getSerializedSize(cell, false));
@@ -69,7 +69,7 @@ public KeyValueDecoder(final InputStream in) {
     }
 
     @Override
-    protected Cell parseCell() throws IOException {
+    protected ExtendedCell parseCell() throws IOException {
       // No tags here
       return KeyValueUtil.createKeyValueFromInputStream(in, false);
     }
@@ -78,7 +78,7 @@ protected Cell parseCell() throws IOException {
   public static class ByteBuffKeyValueDecoder implements Codec.Decoder {
 
     protected final ByteBuff buf;
-    protected Cell current = null;
+    protected ExtendedCell current = null;
 
     public ByteBuffKeyValueDecoder(ByteBuff buf) {
       this.buf = buf;
@@ -101,15 +101,15 @@ public boolean advance() throws IOException {
     }
 
     @Override
-    public Cell current() {
+    public ExtendedCell current() {
       return this.current;
     }
 
-    protected Cell createCell(byte[] buf, int offset, int len) {
+    protected ExtendedCell createCell(byte[] buf, int offset, int len) {
       return new NoTagsKeyValue(buf, offset, len);
     }
 
-    protected Cell createCell(ByteBuffer bb, int pos, int len) {
+    protected ExtendedCell createCell(ByteBuffer bb, int pos, int len) {
       // We know there is not going to be any tags.
       return new NoTagsByteBufferKeyValue(bb, pos, len);
     }
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/KeyValueCodecWithTags.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/KeyValueCodecWithTags.java
index 8c2c20625dfb..655bc4c5f261 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/KeyValueCodecWithTags.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/codec/KeyValueCodecWithTags.java
@@ -22,7 +22,7 @@
 import java.io.OutputStream;
 import java.nio.ByteBuffer;
 import org.apache.hadoop.hbase.ByteBufferKeyValue;
-import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.KeyValueUtil;
@@ -58,7 +58,7 @@ public KeyValueEncoder(final OutputStream out) {
     }
 
     @Override
-    public void write(Cell cell) throws IOException {
+    public void write(ExtendedCell cell) throws IOException {
       checkFlushed();
       // Write tags
       ByteBufferUtils.putInt(this.out, KeyValueUtil.getSerializedSize(cell, true));
@@ -72,7 +72,7 @@ public KeyValueDecoder(final InputStream in) {
     }
 
     @Override
-    protected Cell parseCell() throws IOException {
+    protected ExtendedCell parseCell() throws IOException {
       // create KeyValue with tags
       return KeyValueUtil.createKeyValueFromInputStream(in, true);
     }
@@ -85,12 +85,12 @@ public ByteBuffKeyValueDecoder(ByteBuff buf) {
     }
 
     @Override
-    protected Cell createCell(byte[] buf, int offset, int len) {
+    protected ExtendedCell createCell(byte[] buf, int offset, int len) {
       return new KeyValue(buf, offset, len);
     }
 
     @Override
-    protected Cell createCell(ByteBuffer bb, int pos, int len) {
+    protected ExtendedCell createCell(ByteBuffer bb, int pos, int len) {
       return new ByteBufferKeyValue(bb, pos, len);
     }
   }
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/io/CellOutputStream.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/io/CellOutputStream.java
index d1310137e8ce..8236dceca913 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/io/CellOutputStream.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/io/CellOutputStream.java
@@ -18,7 +18,7 @@
 package org.apache.hadoop.hbase.io;
 
 import java.io.IOException;
-import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.yetus.audience.InterfaceStability;
 
@@ -40,7 +40,7 @@ public interface CellOutputStream {
    * the copy of the Cell that was added in the write.
    * @param cell Cell to write out
    */
-  void write(Cell cell) throws IOException;
+  void write(ExtendedCell cell) throws IOException;
 
   /**
    * Let the implementation decide what to do. Usually means writing accumulated data into a byte[]
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/io/SizedCellScanner.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/io/SizedExtendedCellScanner.java
similarity index 85%
rename from hbase-common/src/main/java/org/apache/hadoop/hbase/io/SizedCellScanner.java
rename to hbase-common/src/main/java/org/apache/hadoop/hbase/io/SizedExtendedCellScanner.java
index 379dfca051a3..8f31ba8fc832 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/io/SizedCellScanner.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/io/SizedExtendedCellScanner.java
@@ -17,15 +17,13 @@
  */
 package org.apache.hadoop.hbase.io;
 
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.yetus.audience.InterfaceAudience;
-import org.apache.yetus.audience.InterfaceStability;
 
 /**
  * A CellScanner that knows its size in memory in bytes. Used playing the CellScanner into an
  * in-memory buffer; knowing the size ahead of time saves on background buffer resizings.
  */
 @InterfaceAudience.Private
-@InterfaceStability.Unstable
-public interface SizedCellScanner extends CellScanner, HeapSize {
+public interface SizedExtendedCellScanner extends ExtendedCellScanner, HeapSize {
 }
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/EncodedDataBlock.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/EncodedDataBlock.java
index 68b300ae60fe..31724723bcd4 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/EncodedDataBlock.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/EncodedDataBlock.java
@@ -29,7 +29,7 @@
 import java.util.List;
 import org.apache.commons.lang3.NotImplementedException;
 import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.io.compress.Compression.Algorithm;
@@ -93,7 +93,7 @@ public EncodedDataBlock(Configuration conf, DataBlockEncoder dataBlockEncoder,
    * @param headerSize header size of the block.
    * @return Forwards sequential iterator.
    */
-  public Iterator<Cell> getIterator(int headerSize) {
+  public Iterator<ExtendedCell> getIterator(int headerSize) {
     final int rawSize = rawKVs.length;
     byte[] encodedDataWithHeader = getEncodedData();
     int bytesToSkip = headerSize + Bytes.SIZEOF_SHORT;
@@ -101,7 +101,7 @@ public Iterator<Cell> getIterator(int headerSize) {
       encodedDataWithHeader.length - bytesToSkip);
     final DataInputStream dis = new DataInputStream(bais);
 
-    return new Iterator<Cell>() {
+    return new Iterator<ExtendedCell>() {
       private ByteBuffer decompressedData = null;
       private Iterator<Boolean> it = isTagsLenZero.iterator();
 
@@ -114,7 +114,7 @@ public boolean hasNext() {
       }
 
       @Override
-      public Cell next() {
+      public ExtendedCell next() {
         if (decompressedData == null) {
           try {
             decompressedData = dataBlockEncoder.decodeKeyValues(dis,
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/NoneEncoder.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/NoneEncoder.java
index 2c48e5b7d7b8..7fb4fd9685e9 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/NoneEncoder.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/NoneEncoder.java
@@ -19,7 +19,7 @@
 
 import java.io.DataOutputStream;
 import java.io.IOException;
-import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.KeyValueUtil;
 import org.apache.hadoop.hbase.PrivateCellUtil;
@@ -37,7 +37,7 @@ public NoneEncoder(DataOutputStream out, HFileBlockDefaultEncodingContext encodi
     this.encodingCtx = encodingCtx;
   }
 
-  public int write(Cell cell) throws IOException {
+  public int write(ExtendedCell cell) throws IOException {
     // We write tags seperately because though there is no tag in KV
     // if the hfilecontext says include tags we need the tags length to be
     // written
diff --git a/hbase-common/src/test/java/org/apache/hadoop/hbase/TestCellComparator.java b/hbase-common/src/test/java/org/apache/hadoop/hbase/TestCellComparator.java
index c4b24728b427..553b39311369 100644
--- a/hbase-common/src/test/java/org/apache/hadoop/hbase/TestCellComparator.java
+++ b/hbase-common/src/test/java/org/apache/hadoop/hbase/TestCellComparator.java
@@ -76,7 +76,7 @@ public void testCompareCells() {
 
     kv1 = new KeyValue(row1, fam1, qual1, 1L, KeyValue.Type.Put);
     kv2 = new KeyValue(row1, fam1, qual1, 1L, KeyValue.Type.Put);
-    assertTrue(CellUtil.equals(kv1, kv2));
+    assertTrue(PrivateCellUtil.equals(kv1, kv2));
   }
 
   @Test
diff --git a/hbase-common/src/test/java/org/apache/hadoop/hbase/TestCellUtil.java b/hbase-common/src/test/java/org/apache/hadoop/hbase/TestCellUtil.java
index dcd796fa3d4f..3ff63ef6ff65 100644
--- a/hbase-common/src/test/java/org/apache/hadoop/hbase/TestCellUtil.java
+++ b/hbase-common/src/test/java/org/apache/hadoop/hbase/TestCellUtil.java
@@ -22,7 +22,6 @@
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.math.BigDecimal;
 import java.nio.ByteBuffer;
@@ -92,7 +91,7 @@ public boolean advance() {
   /**
    * Cell used in test. Has row only.
    */
-  private static class TestCell implements Cell {
+  private static class TestCell implements ExtendedCell {
     private final byte[] row;
 
     TestCell(final int i) {
@@ -116,67 +115,56 @@ public short getRowLength() {
 
     @Override
     public byte[] getFamilyArray() {
-      // TODO Auto-generated method stub
       return null;
     }
 
     @Override
     public int getFamilyOffset() {
-      // TODO Auto-generated method stub
       return 0;
     }
 
     @Override
     public byte getFamilyLength() {
-      // TODO Auto-generated method stub
       return 0;
     }
 
     @Override
     public byte[] getQualifierArray() {
-      // TODO Auto-generated method stub
       return null;
     }
 
     @Override
     public int getQualifierOffset() {
-      // TODO Auto-generated method stub
       return 0;
     }
 
     @Override
     public int getQualifierLength() {
-      // TODO Auto-generated method stub
       return 0;
     }
 
     @Override
     public long getTimestamp() {
-      // TODO Auto-generated method stub
       return 0;
     }
 
     @Override
     public byte getTypeByte() {
-      // TODO Auto-generated method stub
       return 0;
     }
 
     @Override
     public byte[] getValueArray() {
-      // TODO Auto-generated method stub
       return null;
     }
 
     @Override
     public int getValueOffset() {
-      // TODO Auto-generated method stub
       return 0;
     }
 
     @Override
     public int getValueLength() {
-      // TODO Auto-generated method stub
       return 0;
     }
 
@@ -187,25 +175,21 @@ public int getSerializedSize() {
 
     @Override
     public byte[] getTagsArray() {
-      // TODO Auto-generated method stub
       return null;
     }
 
     @Override
     public int getTagsOffset() {
-      // TODO Auto-generated method stub
       return 0;
     }
 
     @Override
     public long getSequenceId() {
-      // TODO Auto-generated method stub
       return 0;
     }
 
     @Override
     public int getTagsLength() {
-      // TODO Auto-generated method stub
       return 0;
     }
 
@@ -213,6 +197,20 @@ public int getTagsLength() {
     public long heapSize() {
       return 0;
     }
+
+    @Override
+    public void setSequenceId(long seqId) throws IOException {
+
+    }
+
+    @Override
+    public void setTimestamp(long ts) throws IOException {
+
+    }
+
+    @Override
+    public void setTimestamp(byte[] ts) throws IOException {
+    }
   }
 
   /**
@@ -444,7 +442,7 @@ public void testCloneCellFieldsFromByteBufferedCell() {
     KeyValue kv =
       new KeyValue(r, f, q, 0, q.length, 1234L, KeyValue.Type.Put, v, 0, v.length, tags);
     ByteBuffer buffer = ByteBuffer.wrap(kv.getBuffer());
-    Cell bbCell = new ByteBufferKeyValue(buffer, 0, buffer.remaining());
+    ExtendedCell bbCell = new ByteBufferKeyValue(buffer, 0, buffer.remaining());
     byte[] rDest = CellUtil.cloneRow(bbCell);
     assertTrue(Bytes.equals(r, rDest));
     byte[] fDest = CellUtil.cloneFamily(bbCell);
@@ -519,30 +517,9 @@ public void testCellFieldsAsPrimitiveTypesFromByteBufferedCell() {
     assertEquals(bd, PrivateCellUtil.getValueAsBigDecimal(bbCell));
   }
 
-  @Test
-  public void testWriteCell() throws IOException {
-    byte[] r = Bytes.toBytes("row1");
-    byte[] f = Bytes.toBytes("cf1");
-    byte[] q1 = Bytes.toBytes("qual1");
-    byte[] v = Bytes.toBytes("val1");
-    byte[] tags = Bytes.toBytes("tag1");
-    KeyValue kv =
-      new KeyValue(r, f, q1, 0, q1.length, 1234L, KeyValue.Type.Put, v, 0, v.length, tags);
-    NonExtendedCell nonExtCell = new NonExtendedCell(kv);
-    ByteArrayOutputStream os = new ByteArrayOutputStream();
-    PrivateCellUtil.writeCell(nonExtCell, os, true);
-    byte[] byteArray = os.toByteArray();
-    KeyValue res = new KeyValue(byteArray);
-    assertTrue(CellUtil.equals(kv, res));
-  }
-
-  // Workaround for jdk 11 - reflective access to interface default methods for testGetType
-  private static abstract class CellForMockito implements Cell {
-  }
-
   @Test
   public void testGetType() {
-    CellForMockito c = Mockito.mock(CellForMockito.class);
+    ExtendedCell c = Mockito.mock(ExtendedCell.class);
     Mockito.when(c.getType()).thenCallRealMethod();
     for (Cell.Type type : Cell.Type.values()) {
       Mockito.when(c.getTypeByte()).thenReturn(type.getCode());
@@ -563,112 +540,4 @@ public void testGetType() {
     } catch (UnsupportedOperationException e) {
     }
   }
-
-  private static class NonExtendedCell implements Cell {
-    private KeyValue kv;
-
-    public NonExtendedCell(KeyValue kv) {
-      this.kv = kv;
-    }
-
-    @Override
-    public byte[] getRowArray() {
-      return this.kv.getRowArray();
-    }
-
-    @Override
-    public int getRowOffset() {
-      return this.kv.getRowOffset();
-    }
-
-    @Override
-    public short getRowLength() {
-      return this.kv.getRowLength();
-    }
-
-    @Override
-    public byte[] getFamilyArray() {
-      return this.kv.getFamilyArray();
-    }
-
-    @Override
-    public int getFamilyOffset() {
-      return this.kv.getFamilyOffset();
-    }
-
-    @Override
-    public byte getFamilyLength() {
-      return this.kv.getFamilyLength();
-    }
-
-    @Override
-    public byte[] getQualifierArray() {
-      return this.kv.getQualifierArray();
-    }
-
-    @Override
-    public int getQualifierOffset() {
-      return this.kv.getQualifierOffset();
-    }
-
-    @Override
-    public int getQualifierLength() {
-      return this.kv.getQualifierLength();
-    }
-
-    @Override
-    public long getTimestamp() {
-      return this.kv.getTimestamp();
-    }
-
-    @Override
-    public byte getTypeByte() {
-      return this.kv.getTypeByte();
-    }
-
-    @Override
-    public long getSequenceId() {
-      return this.kv.getSequenceId();
-    }
-
-    @Override
-    public byte[] getValueArray() {
-      return this.kv.getValueArray();
-    }
-
-    @Override
-    public int getValueOffset() {
-      return this.kv.getValueOffset();
-    }
-
-    @Override
-    public int getValueLength() {
-      return this.kv.getValueLength();
-    }
-
-    @Override
-    public int getSerializedSize() {
-      return this.kv.getSerializedSize();
-    }
-
-    @Override
-    public byte[] getTagsArray() {
-      return this.kv.getTagsArray();
-    }
-
-    @Override
-    public int getTagsOffset() {
-      return this.kv.getTagsOffset();
-    }
-
-    @Override
-    public int getTagsLength() {
-      return this.kv.getTagsLength();
-    }
-
-    @Override
-    public long heapSize() {
-      return this.kv.heapSize();
-    }
-  }
 }
diff --git a/hbase-common/src/test/java/org/apache/hadoop/hbase/codec/TestCellCodec.java b/hbase-common/src/test/java/org/apache/hadoop/hbase/codec/TestCellCodec.java
index 9963e37c17f6..3508419cea78 100644
--- a/hbase-common/src/test/java/org/apache/hadoop/hbase/codec/TestCellCodec.java
+++ b/hbase-common/src/test/java/org/apache/hadoop/hbase/codec/TestCellCodec.java
@@ -26,10 +26,10 @@
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
 import java.io.IOException;
-import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.KeyValue;
+import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.testclassification.MiscTests;
 import org.apache.hadoop.hbase.testclassification.SmallTests;
 import org.apache.hadoop.hbase.util.Bytes;
@@ -113,14 +113,14 @@ public void testThree() throws IOException {
     DataInputStream dis = new DataInputStream(cis);
     Codec.Decoder decoder = codec.getDecoder(dis);
     assertTrue(decoder.advance());
-    Cell c = decoder.current();
-    assertTrue(CellUtil.equals(c, kv1));
+    ExtendedCell c = decoder.current();
+    assertTrue(PrivateCellUtil.equals(c, kv1));
     assertTrue(decoder.advance());
     c = decoder.current();
-    assertTrue(CellUtil.equals(c, kv2));
+    assertTrue(PrivateCellUtil.equals(c, kv2));
     assertTrue(decoder.advance());
     c = decoder.current();
-    assertTrue(CellUtil.equals(c, kv3));
+    assertTrue(PrivateCellUtil.equals(c, kv3));
     assertFalse(decoder.advance());
     dis.close();
     assertEquals(offset, cis.getCount());
diff --git a/hbase-common/src/test/java/org/apache/hadoop/hbase/codec/TestCellCodecWithTags.java b/hbase-common/src/test/java/org/apache/hadoop/hbase/codec/TestCellCodecWithTags.java
index b44473ee49e6..17c95eb2c729 100644
--- a/hbase-common/src/test/java/org/apache/hadoop/hbase/codec/TestCellCodecWithTags.java
+++ b/hbase-common/src/test/java/org/apache/hadoop/hbase/codec/TestCellCodecWithTags.java
@@ -28,8 +28,8 @@
 import java.io.IOException;
 import java.util.List;
 import org.apache.hadoop.hbase.ArrayBackedTag;
-import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.KeyValue;
@@ -58,15 +58,15 @@ public void testCellWithTag() throws IOException {
     DataOutputStream dos = new DataOutputStream(cos);
     Codec codec = new CellCodecWithTags();
     Codec.Encoder encoder = codec.getEncoder(dos);
-    final Cell cell1 = new KeyValue(Bytes.toBytes("r"), Bytes.toBytes("f"), Bytes.toBytes("1"),
-      HConstants.LATEST_TIMESTAMP, Bytes.toBytes("1"),
+    final ExtendedCell cell1 = new KeyValue(Bytes.toBytes("r"), Bytes.toBytes("f"),
+      Bytes.toBytes("1"), HConstants.LATEST_TIMESTAMP, Bytes.toBytes("1"),
       new Tag[] { new ArrayBackedTag((byte) 1, Bytes.toBytes("teststring1")),
         new ArrayBackedTag((byte) 2, Bytes.toBytes("teststring2")) });
-    final Cell cell2 = new KeyValue(Bytes.toBytes("r"), Bytes.toBytes("f"), Bytes.toBytes("2"),
-      HConstants.LATEST_TIMESTAMP, Bytes.toBytes("2"),
+    final ExtendedCell cell2 = new KeyValue(Bytes.toBytes("r"), Bytes.toBytes("f"),
+      Bytes.toBytes("2"), HConstants.LATEST_TIMESTAMP, Bytes.toBytes("2"),
       new Tag[] { new ArrayBackedTag((byte) 1, Bytes.toBytes("teststring3")), });
-    final Cell cell3 = new KeyValue(Bytes.toBytes("r"), Bytes.toBytes("f"), Bytes.toBytes("3"),
-      HConstants.LATEST_TIMESTAMP, Bytes.toBytes("3"),
+    final ExtendedCell cell3 = new KeyValue(Bytes.toBytes("r"), Bytes.toBytes("f"),
+      Bytes.toBytes("3"), HConstants.LATEST_TIMESTAMP, Bytes.toBytes("3"),
       new Tag[] { new ArrayBackedTag((byte) 2, Bytes.toBytes("teststring4")),
         new ArrayBackedTag((byte) 2, Bytes.toBytes("teststring5")),
         new ArrayBackedTag((byte) 1, Bytes.toBytes("teststring6")) });
@@ -81,7 +81,7 @@ public void testCellWithTag() throws IOException {
     DataInputStream dis = new DataInputStream(cis);
     Codec.Decoder decoder = codec.getDecoder(dis);
     assertTrue(decoder.advance());
-    Cell c = decoder.current();
+    ExtendedCell c = decoder.current();
     assertTrue(CellUtil.equals(c, cell1));
     List<Tag> tags = PrivateCellUtil.getTags(c);
     assertEquals(2, tags.size());
diff --git a/hbase-common/src/test/java/org/apache/hadoop/hbase/codec/TestKeyValueCodecWithTags.java b/hbase-common/src/test/java/org/apache/hadoop/hbase/codec/TestKeyValueCodecWithTags.java
index 66a874e5c5ec..e2bdecbf7c6b 100644
--- a/hbase-common/src/test/java/org/apache/hadoop/hbase/codec/TestKeyValueCodecWithTags.java
+++ b/hbase-common/src/test/java/org/apache/hadoop/hbase/codec/TestKeyValueCodecWithTags.java
@@ -28,8 +28,8 @@
 import java.io.IOException;
 import java.util.List;
 import org.apache.hadoop.hbase.ArrayBackedTag;
-import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.KeyValue;
@@ -81,7 +81,7 @@ public void testKeyValueWithTag() throws IOException {
     DataInputStream dis = new DataInputStream(cis);
     Codec.Decoder decoder = codec.getDecoder(dis);
     assertTrue(decoder.advance());
-    Cell c = decoder.current();
+    ExtendedCell c = decoder.current();
     assertTrue(CellUtil.equals(c, kv1));
     List<Tag> tags = PrivateCellUtil.getTags(c);
     assertEquals(2, tags.size());
diff --git a/hbase-endpoint/src/test/java/org/apache/hadoop/hbase/client/TestRpcControllerFactory.java b/hbase-endpoint/src/test/java/org/apache/hadoop/hbase/client/TestRpcControllerFactory.java
index 9d122fb0b81c..cb6e14d1b278 100644
--- a/hbase-endpoint/src/test/java/org/apache/hadoop/hbase/client/TestRpcControllerFactory.java
+++ b/hbase-endpoint/src/test/java/org/apache/hadoop/hbase/client/TestRpcControllerFactory.java
@@ -26,8 +26,8 @@
 import java.util.List;
 import java.util.concurrent.atomic.AtomicInteger;
 import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.hbase.CellScannable;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCellScannable;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
 import org.apache.hadoop.hbase.HConstants;
@@ -72,13 +72,14 @@ public HBaseRpcController newController() {
     }
 
     @Override
-    public HBaseRpcController newController(RegionInfo regionInfo, CellScanner cellScanner) {
+    public HBaseRpcController newController(RegionInfo regionInfo,
+      ExtendedCellScanner cellScanner) {
       return new CountingRpcController(super.newController(regionInfo, cellScanner));
     }
 
     @Override
     public HBaseRpcController newController(RegionInfo regionInfo,
-      List<CellScannable> cellIterables) {
+      List<ExtendedCellScannable> cellIterables) {
       return new CountingRpcController(super.newController(regionInfo, cellIterables));
     }
   }
diff --git a/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/CellSerialization.java b/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/CellSerialization.java
index 9d567f95a0e0..456f99629e34 100644
--- a/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/CellSerialization.java
+++ b/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/CellSerialization.java
@@ -23,6 +23,7 @@
 import java.io.InputStream;
 import java.io.OutputStream;
 import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.KeyValueUtil;
 import org.apache.hadoop.hbase.PrivateCellUtil;
@@ -85,7 +86,12 @@ public void open(OutputStream os) throws IOException {
     @Override
     public void serialize(Cell kv) throws IOException {
       dos.writeInt(PrivateCellUtil.estimatedSerializedSizeOf(kv) - Bytes.SIZEOF_INT);
-      PrivateCellUtil.writeCell(kv, dos, true);
+      if (kv instanceof ExtendedCell) {
+        ((ExtendedCell) kv).write(dos, true);
+      } else {
+        throw new UnsupportedOperationException(
+          "Unsupported cell type: " + kv.getClass().getName());
+      }
     }
   }
 }
diff --git a/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/CellSortReducer.java b/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/CellSortReducer.java
index 9380b0e71336..dd6ff00497f4 100644
--- a/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/CellSortReducer.java
+++ b/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/CellSortReducer.java
@@ -17,10 +17,10 @@
  */
 package org.apache.hadoop.hbase.mapreduce;
 
-import java.io.IOException;
 import java.util.TreeSet;
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellComparator;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
 import org.apache.hadoop.hbase.util.MapReduceExtendedCell;
@@ -38,19 +38,17 @@ public class CellSortReducer
   protected void reduce(ImmutableBytesWritable row, Iterable<Cell> kvs,
     Reducer<ImmutableBytesWritable, Cell, ImmutableBytesWritable, Cell>.Context context)
     throws java.io.IOException, InterruptedException {
-    TreeSet<Cell> map = new TreeSet<>(CellComparator.getInstance());
+    TreeSet<ExtendedCell> set = new TreeSet<>(CellComparator.getInstance());
     for (Cell kv : kvs) {
-      try {
-        map.add(PrivateCellUtil.deepClone(kv));
-      } catch (CloneNotSupportedException e) {
-        throw new IOException(e);
-      }
+      set.add(PrivateCellUtil.ensureExtendedCell(kv));
     }
-    context.setStatus("Read " + map.getClass());
+    context.setStatus("Read " + set.getClass());
     int index = 0;
-    for (Cell kv : map) {
+    for (ExtendedCell kv : set) {
       context.write(row, new MapReduceExtendedCell(kv));
-      if (++index % 100 == 0) context.setStatus("Wrote " + index);
+      if (++index % 100 == 0) {
+        context.setStatus("Wrote " + index);
+      }
     }
   }
 }
diff --git a/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/ExtendedCellSerialization.java b/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/ExtendedCellSerialization.java
index c784b2561881..9e89c7896261 100644
--- a/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/ExtendedCellSerialization.java
+++ b/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/ExtendedCellSerialization.java
@@ -94,7 +94,7 @@ public void open(OutputStream os) throws IOException {
     @Override
     public void serialize(ExtendedCell kv) throws IOException {
       dos.writeInt(PrivateCellUtil.estimatedSerializedSizeOf(kv) - Bytes.SIZEOF_INT);
-      PrivateCellUtil.writeCell(kv, dos, true);
+      kv.write(dos, true);
       dos.writeLong(kv.getSequenceId());
     }
   }
diff --git a/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/HFileOutputFormat2.java b/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/HFileOutputFormat2.java
index 225a2dc6fe2b..51e23abc8ca6 100644
--- a/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/HFileOutputFormat2.java
+++ b/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/HFileOutputFormat2.java
@@ -240,13 +240,13 @@ static <V extends Cell> RecordWriter<ImmutableBytesWritable, V> createRecordWrit
 
       @Override
       public void write(ImmutableBytesWritable row, V cell) throws IOException {
-        Cell kv = cell;
         // null input == user explicitly wants to flush
-        if (row == null && kv == null) {
+        if (row == null && cell == null) {
           rollWriters(null);
           return;
         }
 
+        ExtendedCell kv = PrivateCellUtil.ensureExtendedCell(cell);
         byte[] rowKey = CellUtil.cloneRow(kv);
         int length = (PrivateCellUtil.estimatedSerializedSizeOf(kv)) - Bytes.SIZEOF_INT;
         byte[] family = CellUtil.cloneFamily(kv);
diff --git a/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/Import.java b/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/Import.java
index 6605c6783ba8..8a8b846959b6 100644
--- a/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/Import.java
+++ b/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/Import.java
@@ -38,6 +38,7 @@
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellComparator;
 import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.KeyValueUtil;
@@ -51,6 +52,7 @@
 import org.apache.hadoop.hbase.client.Delete;
 import org.apache.hadoop.hbase.client.Durability;
 import org.apache.hadoop.hbase.client.Mutation;
+import org.apache.hadoop.hbase.client.PackagePrivateFieldAccessor;
 import org.apache.hadoop.hbase.client.Put;
 import org.apache.hadoop.hbase.client.RegionLocator;
 import org.apache.hadoop.hbase.client.Result;
@@ -114,7 +116,7 @@ public int getPartition(CellWritableComparable key, Cell value, int numPartition
 
   public static class CellWritableComparable implements WritableComparable<CellWritableComparable> {
 
-    private Cell kv = null;
+    private ExtendedCell kv = null;
 
     static {
       // register this comparator
@@ -125,7 +127,7 @@ public CellWritableComparable() {
     }
 
     public CellWritableComparable(Cell kv) {
-      this.kv = kv;
+      this.kv = (ExtendedCell) kv;
     }
 
     @Override
@@ -174,7 +176,7 @@ protected void reduce(CellWritableComparable row, Iterable<Cell> kvs,
       int index = 0;
       for (Cell kv : kvs) {
         context.write(new ImmutableBytesWritable(CellUtil.cloneRow(kv)),
-          new MapReduceExtendedCell(kv));
+          new MapReduceExtendedCell(PrivateCellUtil.ensureExtendedCell(kv)));
         if (++index % 100 == 0) context.setStatus("Wrote " + index + " KeyValues, "
           + "and the rowkey whose is being wrote is " + Bytes.toString(kv.getRowArray()));
       }
@@ -203,10 +205,12 @@ public void map(ImmutableBytesWritable row, Result value, Context context) throw
           filter == null || !filter.filterRowKey(
             PrivateCellUtil.createFirstOnRow(row.get(), row.getOffset(), (short) row.getLength()))
         ) {
-          for (Cell kv : value.rawCells()) {
+          for (ExtendedCell kv : PackagePrivateFieldAccessor.getExtendedRawCells(value)) {
             kv = filterKv(filter, kv);
             // skip if we filtered it out
-            if (kv == null) continue;
+            if (kv == null) {
+              continue;
+            }
             Cell ret = convertKv(kv, cfRenameMap);
             context.write(new CellWritableComparable(ret), ret);
           }
@@ -267,10 +271,12 @@ public void map(ImmutableBytesWritable row, Result value, Context context) throw
           filter == null || !filter.filterRowKey(
             PrivateCellUtil.createFirstOnRow(row.get(), row.getOffset(), (short) row.getLength()))
         ) {
-          for (Cell kv : value.rawCells()) {
+          for (ExtendedCell kv : PackagePrivateFieldAccessor.getExtendedRawCells(value)) {
             kv = filterKv(filter, kv);
             // skip if we filtered it out
-            if (kv == null) continue;
+            if (kv == null) {
+              continue;
+            }
             context.write(row, new MapReduceExtendedCell(convertKv(kv, cfRenameMap)));
           }
         }
@@ -330,10 +336,12 @@ private void writeResult(ImmutableBytesWritable key, Result result, Context cont
 
     protected void processKV(ImmutableBytesWritable key, Result result, Context context, Put put,
       Delete delete) throws IOException, InterruptedException {
-      for (Cell kv : result.rawCells()) {
+      for (ExtendedCell kv : PackagePrivateFieldAccessor.getExtendedRawCells(result)) {
         kv = filterKv(filter, kv);
         // skip if we filter it out
-        if (kv == null) continue;
+        if (kv == null) {
+          continue;
+        }
 
         kv = convertKv(kv, cfRenameMap);
         // Deletes and Puts are gathered and written when finished
@@ -476,7 +484,7 @@ private static ArrayList<byte[]> toQuotedByteArrays(String... stringArgs) {
    * @return <tt>null</tt> if the key should not be written, otherwise returns the original
    *         {@link Cell}
    */
-  public static Cell filterKv(Filter filter, Cell c) throws IOException {
+  public static ExtendedCell filterKv(Filter filter, ExtendedCell c) throws IOException {
     // apply the filter and skip this kv if the filter doesn't apply
     if (filter != null) {
       Filter.ReturnCode code = filter.filterCell(c);
@@ -495,7 +503,7 @@ public static Cell filterKv(Filter filter, Cell c) throws IOException {
   }
 
   // helper: create a new KeyValue based on CF rename map
-  private static Cell convertKv(Cell kv, Map<byte[], byte[]> cfRenameMap) {
+  private static ExtendedCell convertKv(ExtendedCell kv, Map<byte[], byte[]> cfRenameMap) {
     if (cfRenameMap != null) {
       // If there's a rename mapping for this CF, create a new KeyValue
       byte[] newCfName = cfRenameMap.get(CellUtil.cloneFamily(kv));
diff --git a/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/PutCombiner.java b/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/PutCombiner.java
index 90dc5c1d555f..cd25736bd6ee 100644
--- a/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/PutCombiner.java
+++ b/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/PutCombiner.java
@@ -21,10 +21,8 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
-import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.ExtendedCell;
-import org.apache.hadoop.hbase.KeyValue;
-import org.apache.hadoop.hbase.KeyValueUtil;
+import org.apache.hadoop.hbase.client.PackagePrivateFieldAccessor;
 import org.apache.hadoop.hbase.client.Put;
 import org.apache.hadoop.mapreduce.Reducer;
 import org.apache.yetus.audience.InterfaceAudience;
@@ -51,45 +49,51 @@ protected void reduce(K row, Iterable<Put> vals, Context context)
       context.getConfiguration().getLong("putcombiner.row.threshold", 1L * (1 << 30));
     int cnt = 0;
     long curSize = 0;
-    Put put = null;
-    Map<byte[], List<Cell>> familyMap = null;
+    Put combinedPut = null;
+    Map<byte[], List<ExtendedCell>> combinedFamilyMap = null;
     for (Put p : vals) {
       cnt++;
-      if (put == null) {
-        put = p;
-        familyMap = put.getFamilyCellMap();
+      if (combinedPut == null) {
+        combinedPut = p;
+        combinedFamilyMap = PackagePrivateFieldAccessor.getExtendedFamilyCellMap(combinedPut);
       } else {
-        for (Entry<byte[], List<Cell>> entry : p.getFamilyCellMap().entrySet()) {
-          List<Cell> cells = familyMap.get(entry.getKey());
-          List<Cell> kvs = (cells != null) ? (List<Cell>) cells : null;
-          for (Cell cell : entry.getValue()) {
-            KeyValue kv = KeyValueUtil.ensureKeyValue((ExtendedCell) cell);
-            curSize += kv.heapSize();
-            if (kvs != null) {
-              kvs.add(kv);
+        for (Entry<byte[], List<ExtendedCell>> entry : PackagePrivateFieldAccessor
+          .getExtendedFamilyCellMap(p).entrySet()) {
+          List<ExtendedCell> existCells = combinedFamilyMap.get(entry.getKey());
+          if (existCells == null) {
+            // no cells for this family yet, just put it
+            combinedFamilyMap.put(entry.getKey(), entry.getValue());
+            // do not forget to calculate the size
+            for (ExtendedCell cell : entry.getValue()) {
+              curSize += cell.heapSize();
+            }
+          } else {
+            // otherwise just add the cells to the existent list for this family
+            for (ExtendedCell cell : entry.getValue()) {
+              existCells.add(cell);
+              curSize += cell.heapSize();
             }
           }
-          if (cells == null) {
-            familyMap.put(entry.getKey(), entry.getValue());
-          }
         }
-        if (cnt % 10 == 0) context.setStatus("Combine " + cnt);
+        if (cnt % 10 == 0) {
+          context.setStatus("Combine " + cnt);
+        }
         if (curSize > threshold) {
           if (LOG.isDebugEnabled()) {
             LOG.debug(String.format("Combined %d Put(s) into %d.", cnt, 1));
           }
-          context.write(row, put);
-          put = null;
+          context.write(row, combinedPut);
+          combinedPut = null;
           curSize = 0;
           cnt = 0;
         }
       }
     }
-    if (put != null) {
+    if (combinedPut != null) {
       if (LOG.isDebugEnabled()) {
         LOG.debug(String.format("Combined %d Put(s) into %d.", cnt, 1));
       }
-      context.write(row, put);
+      context.write(row, combinedPut);
     }
   }
 }
diff --git a/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/PutSortReducer.java b/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/PutSortReducer.java
index b4061d6be6a9..c8f32c205fb7 100644
--- a/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/PutSortReducer.java
+++ b/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/PutSortReducer.java
@@ -24,7 +24,6 @@
 import java.util.TreeSet;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.ArrayBackedTag;
-import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellComparator;
 import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.KeyValue;
@@ -32,6 +31,7 @@
 import org.apache.hadoop.hbase.Tag;
 import org.apache.hadoop.hbase.TagType;
 import org.apache.hadoop.hbase.TagUtil;
+import org.apache.hadoop.hbase.client.PackagePrivateFieldAccessor;
 import org.apache.hadoop.hbase.client.Put;
 import org.apache.hadoop.hbase.exceptions.DeserializationException;
 import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
@@ -62,9 +62,9 @@ public class PutSortReducer
   }
 
   @Override
-  protected void reduce(ImmutableBytesWritable row, java.lang.Iterable<Put> puts,
+  protected void reduce(ImmutableBytesWritable row, Iterable<Put> puts,
     Reducer<ImmutableBytesWritable, Put, ImmutableBytesWritable, KeyValue>.Context context)
-    throws java.io.IOException, InterruptedException {
+    throws IOException, InterruptedException {
     // although reduce() is called per-row, handle pathological case
     long threshold =
       context.getConfiguration().getLong("putsortreducer.row.threshold", 1L * (1 << 30));
@@ -100,8 +100,9 @@ protected void reduce(ImmutableBytesWritable row, java.lang.Iterable<Put> puts,
           // just ignoring the bad one?
           throw new IOException("Invalid visibility expression found in mutation " + p, e);
         }
-        for (List<Cell> cells : p.getFamilyCellMap().values()) {
-          for (ExtendedCell cell : (List<ExtendedCell>) (List) cells) {
+        for (List<ExtendedCell> cells : PackagePrivateFieldAccessor.getExtendedFamilyCellMap(p)
+          .values()) {
+          for (ExtendedCell cell : cells) {
             // Creating the KV which needs to be directly written to HFiles. Using the Facade
             // KVCreator for creation of kvs.
             KeyValue kv = null;
diff --git a/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/WALPlayer.java b/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/WALPlayer.java
index 37e99c096e5c..888e285f340e 100644
--- a/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/WALPlayer.java
+++ b/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/WALPlayer.java
@@ -117,7 +117,8 @@ public void map(WALKey key, WALEdit value, Context context) throws IOException {
             byte[] outKey = multiTableSupport
               ? Bytes.add(table.getName(), Bytes.toBytes(tableSeparator), CellUtil.cloneRow(cell))
               : CellUtil.cloneRow(cell);
-            context.write(new ImmutableBytesWritable(outKey), new MapReduceExtendedCell(cell));
+            context.write(new ImmutableBytesWritable(outKey),
+              new MapReduceExtendedCell(PrivateCellUtil.ensureExtendedCell(cell)));
           }
         }
       } catch (InterruptedException e) {
diff --git a/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/util/MapReduceExtendedCell.java b/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/util/MapReduceExtendedCell.java
index ca0d5f63a078..4233e96f2c79 100644
--- a/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/util/MapReduceExtendedCell.java
+++ b/hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/util/MapReduceExtendedCell.java
@@ -21,7 +21,6 @@
 import java.io.OutputStream;
 import java.nio.ByteBuffer;
 import org.apache.hadoop.hbase.ByteBufferExtendedCell;
-import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.PrivateCellUtil;
@@ -33,9 +32,9 @@
 @InterfaceAudience.Private
 public class MapReduceExtendedCell extends ByteBufferExtendedCell {
 
-  private final Cell cell;
+  private final ExtendedCell cell;
 
-  public MapReduceExtendedCell(Cell cell) {
+  public MapReduceExtendedCell(ExtendedCell cell) {
     this.cell = cell;
   }
 
@@ -226,17 +225,17 @@ public String toString() {
 
   @Override
   public void setSequenceId(long seqId) throws IOException {
-    PrivateCellUtil.setSequenceId(cell, seqId);
+    cell.setSequenceId(seqId);
   }
 
   @Override
   public void setTimestamp(long ts) throws IOException {
-    PrivateCellUtil.setTimestamp(cell, ts);
+    cell.setTimestamp(ts);
   }
 
   @Override
   public void setTimestamp(byte[] ts) throws IOException {
-    PrivateCellUtil.setTimestamp(cell, ts);
+    cell.setTimestamp(ts);
   }
 
   @Override
@@ -246,7 +245,7 @@ public long heapSize() {
 
   @Override
   public int write(OutputStream out, boolean withTags) throws IOException {
-    return PrivateCellUtil.writeCell(cell, out, withTags);
+    return cell.write(out, withTags);
   }
 
   @Override
@@ -256,15 +255,11 @@ public int getSerializedSize(boolean withTags) {
 
   @Override
   public void write(ByteBuffer buf, int offset) {
-    PrivateCellUtil.writeCellToBuffer(cell, buf, offset);
+    cell.write(buf, offset);
   }
 
   @Override
   public ExtendedCell deepClone() {
-    try {
-      return (ExtendedCell) PrivateCellUtil.deepClone(cell);
-    } catch (CloneNotSupportedException e) {
-      throw new RuntimeException(e);
-    }
+    return cell.deepClone();
   }
 }
diff --git a/hbase-mapreduce/src/test/java/org/apache/hadoop/hbase/mapreduce/TestHFileOutputFormat2.java b/hbase-mapreduce/src/test/java/org/apache/hadoop/hbase/mapreduce/TestHFileOutputFormat2.java
index e67ee3dbb736..0714f27e64d9 100644
--- a/hbase-mapreduce/src/test/java/org/apache/hadoop/hbase/mapreduce/TestHFileOutputFormat2.java
+++ b/hbase-mapreduce/src/test/java/org/apache/hadoop/hbase/mapreduce/TestHFileOutputFormat2.java
@@ -56,6 +56,7 @@
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.CompatibilitySingletonFactory;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
@@ -518,7 +519,7 @@ public void test_WritingTagData() throws Exception {
           HFile.createReader(fs, keyFileStatus.getPath(), new CacheConfig(conf), true, conf);
         HFileScanner scanner = reader.getScanner(conf, false, false, false);
         scanner.seekTo();
-        Cell cell = scanner.getCell();
+        ExtendedCell cell = scanner.getCell();
         List<Tag> tagsFromCell = PrivateCellUtil.getTags(cell);
         assertTrue(tagsFromCell.size() > 0);
         for (Tag tag : tagsFromCell) {
diff --git a/hbase-mapreduce/src/test/java/org/apache/hadoop/hbase/mapreduce/TestImportExport.java b/hbase-mapreduce/src/test/java/org/apache/hadoop/hbase/mapreduce/TestImportExport.java
index 5e3e52de6ad4..25bec82da09e 100644
--- a/hbase-mapreduce/src/test/java/org/apache/hadoop/hbase/mapreduce/TestImportExport.java
+++ b/hbase-mapreduce/src/test/java/org/apache/hadoop/hbase/mapreduce/TestImportExport.java
@@ -42,9 +42,9 @@
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hbase.ArrayBackedTag;
 import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.CellScanner;
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.ExtendedCell;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
 import org.apache.hadoop.hbase.HConstants;
@@ -60,6 +60,7 @@
 import org.apache.hadoop.hbase.client.Durability;
 import org.apache.hadoop.hbase.client.Get;
 import org.apache.hadoop.hbase.client.Mutation;
+import org.apache.hadoop.hbase.client.PackagePrivateFieldAccessor;
 import org.apache.hadoop.hbase.client.Put;
 import org.apache.hadoop.hbase.client.RegionInfo;
 import org.apache.hadoop.hbase.client.Result;
@@ -365,7 +366,7 @@ public void testWithDeletes() throws Throwable {
       s.setRaw(true);
       ResultScanner scanner = t.getScanner(s);
       Result r = scanner.next();
-      Cell[] res = r.rawCells();
+      ExtendedCell[] res = PackagePrivateFieldAccessor.getExtendedRawCells(r);
       assertTrue(PrivateCellUtil.isDeleteFamily(res[0]));
       assertEquals(now + 4, res[1].getTimestamp());
       assertEquals(now + 3, res[2].getTimestamp());
@@ -820,7 +821,7 @@ public void testTagsAddition() throws Throwable {
   }
 
   private void checkWhetherTagExists(TableName table, boolean tagExists) throws IOException {
-    List<Cell> values = new ArrayList<>();
+    List<ExtendedCell> values = new ArrayList<>();
     for (HRegion region : UTIL.getHBaseCluster().getRegions(table)) {
       Scan scan = new Scan();
       // Make sure to set rawScan to true so that we will get Delete Markers.
@@ -830,13 +831,13 @@ private void checkWhetherTagExists(TableName table, boolean tagExists) throws IO
       // Need to use RegionScanner instead of table#getScanner since the latter will
       // not return tags since it will go through rpc layer and remove tags intentionally.
       RegionScanner scanner = region.getScanner(scan);
-      scanner.next(values);
+      scanner.next((List) values);
       if (!values.isEmpty()) {
         break;
       }
     }
     boolean deleteFound = false;
-    for (Cell cell : values) {
+    for (ExtendedCell cell : values) {
       if (PrivateCellUtil.isDelete(cell.getType().getCode())) {
         deleteFound = true;
         List<Tag> tags = PrivateCellUtil.getTags(cell);
@@ -881,11 +882,11 @@ public void preBatchMutate(ObserverContext<RegionCoprocessorEnvironment> c,
         }
         Tag sourceOpTag = new ArrayBackedTag(TEST_TAG_TYPE, sourceOpAttr);
         List<Cell> updatedCells = new ArrayList<>();
-        for (CellScanner cellScanner = m.cellScanner(); cellScanner.advance();) {
-          Cell cell = cellScanner.current();
+        for (ExtendedCellScanner cellScanner = m.cellScanner(); cellScanner.advance();) {
+          ExtendedCell cell = cellScanner.current();
           List<Tag> tags = PrivateCellUtil.getTags(cell);
           tags.add(sourceOpTag);
-          Cell updatedCell = PrivateCellUtil.createCell((ExtendedCell) cell, tags);
+          Cell updatedCell = PrivateCellUtil.createCell(cell, tags);
           updatedCells.add(updatedCell);
         }
         m.getFamilyCellMap().clear();
@@ -934,9 +935,10 @@ public void testTagsWithEmptyCodec() throws Exception {
       int count = 0;
       Result result;
       while ((result = scanner.next()) != null) {
-        List<Cell> cells = result.listCells();
+        List<ExtendedCell> cells =
+          Arrays.asList(PackagePrivateFieldAccessor.getExtendedRawCells(result));
         assertEquals(2, cells.size());
-        Cell cell = cells.get(0);
+        ExtendedCell cell = cells.get(0);
         assertTrue(CellUtil.isDelete(cell));
         List<Tag> tags = PrivateCellUtil.getTags(cell);
         assertEquals(0, tags.size());
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/client/AsyncRegionReplicationRetryingCaller.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/client/AsyncRegionReplicationRetryingCaller.java
index e2b45fe30c3c..a0ca5b990dd1 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/client/AsyncRegionReplicationRetryingCaller.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/client/AsyncRegionReplicationRetryingCaller.java
@@ -22,8 +22,8 @@
 import java.io.IOException;
 import java.util.Collections;
 import java.util.List;
-import org.apache.hadoop.hbase.CellScanner;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HRegionLocation;
 import org.apache.hadoop.hbase.protobuf.ReplicationProtobufUtil;
 import org.apache.hadoop.hbase.util.Pair;
@@ -94,7 +94,7 @@ private void call(HRegionLocation loc) {
         err -> conn.getLocator().updateCachedLocationOnError(loc, err));
       return;
     }
-    Pair<ReplicateWALEntryRequest, CellScanner> pair = ReplicationProtobufUtil
+    Pair<ReplicateWALEntryRequest, ExtendedCellScanner> pair = ReplicationProtobufUtil
       .buildReplicateWALEntryRequest(entries, replica.getEncodedNameAsBytes(), null, null, null);
     resetCallTimeout();
     controller.setCellScanner(pair.getSecond());
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/client/AsyncRegionServerAdmin.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/client/AsyncRegionServerAdmin.java
index f5fcc02e9186..81707fe1f16b 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/client/AsyncRegionServerAdmin.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/client/AsyncRegionServerAdmin.java
@@ -19,7 +19,7 @@
 
 import java.io.IOException;
 import java.util.concurrent.CompletableFuture;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.ipc.HBaseRpcController;
 import org.apache.yetus.audience.InterfaceAudience;
@@ -95,7 +95,8 @@ private interface RpcCall<RESP> {
     void call(AdminService.Interface stub, HBaseRpcController controller, RpcCallback<RESP> done);
   }
 
-  private <RESP> CompletableFuture<RESP> call(RpcCall<RESP> rpcCall, CellScanner cellScanner) {
+  private <RESP> CompletableFuture<RESP> call(RpcCall<RESP> rpcCall,
+    ExtendedCellScanner cellScanner) {
     CompletableFuture<RESP> future = new CompletableFuture<>();
     HBaseRpcController controller = conn.rpcControllerFactory.newController(null, cellScanner);
     try {
@@ -158,8 +159,8 @@ public CompletableFuture<CompactRegionResponse> compactRegion(CompactRegionReque
     return call((stub, controller, done) -> stub.compactRegion(controller, request, done));
   }
 
-  public CompletableFuture<ReplicateWALEntryResponse>
-    replicateWALEntry(ReplicateWALEntryRequest request, CellScanner cellScanner, int timeout) {
+  public CompletableFuture<ReplicateWALEntryResponse> replicateWALEntry(
+    ReplicateWALEntryRequest request, ExtendedCellScanner cellScanner, int timeout) {
     return call((stub, controller, done) -> {
       controller.setCallTimeout(timeout);
       stub.replicateWALEntry(controller, request, done);
@@ -167,7 +168,7 @@ public CompletableFuture<CompactRegionResponse> compactRegion(CompactRegionReque
   }
 
   public CompletableFuture<ReplicateWALEntryResponse> replay(ReplicateWALEntryRequest request,
-    CellScanner cellScanner) {
+    ExtendedCellScanner cellScanner) {
     return call((stub, controller, done) -> stub.replay(controller, request, done), cellScanner);
   }
 
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/codec/MessageCodec.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/codec/MessageCodec.java
index a6d6940e1e4c..8482a819c0d5 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/codec/MessageCodec.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/codec/MessageCodec.java
@@ -20,8 +20,8 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
-import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellBuilderType;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.ExtendedCellBuilder;
 import org.apache.hadoop.hbase.ExtendedCellBuilderFactory;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
@@ -46,7 +46,7 @@ static class MessageEncoder extends BaseEncoder {
     }
 
     @Override
-    public void write(Cell cell) throws IOException {
+    public void write(ExtendedCell cell) throws IOException {
       checkFlushed();
       CellProtos.Cell.Builder builder = CellProtos.Cell.newBuilder();
       // This copies bytes from Cell to ByteString. I don't see anyway around the copy.
@@ -75,7 +75,7 @@ static class MessageDecoder extends BaseDecoder {
     }
 
     @Override
-    protected Cell parseCell() throws IOException {
+    protected ExtendedCell parseCell() throws IOException {
       return ProtobufUtil.toCell(cellBuilder, CellProtos.Cell.parseDelimitedFrom(this.in), false);
     }
   }
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/HFilePrettyPrinter.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/HFilePrettyPrinter.java
index 0c32303746c0..9900aa63cab6 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/HFilePrettyPrinter.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/HFilePrettyPrinter.java
@@ -48,6 +48,7 @@
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellComparator;
 import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.hadoop.hbase.HConstants;
@@ -369,7 +370,7 @@ private void scanKeysValues(Path file, KeyValueStatsCollector fileStats, HFileSc
     Set<String> foundMobFiles = new LinkedHashSet<>(FOUND_MOB_FILES_CACHE_CAPACITY);
     Set<String> missingMobFiles = new LinkedHashSet<>(MISSING_MOB_FILES_CACHE_CAPACITY);
     do {
-      Cell cell = scanner.getCell();
+      ExtendedCell cell = scanner.getCell();
       if (row != null && row.length != 0) {
         int result = CellComparator.getInstance().compareRows(cell, row, 0, row.length);
         if (result > 0) {
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/CallRunner.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/CallRunner.java
index 0134e11d8914..ce3ea3fd9414 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/CallRunner.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/CallRunner.java
@@ -23,7 +23,7 @@
 import java.net.InetSocketAddress;
 import java.nio.channels.ClosedChannelException;
 import org.apache.hadoop.hbase.CallDroppedException;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.hadoop.hbase.exceptions.TimeoutIOException;
 import org.apache.hadoop.hbase.monitoring.MonitoredRPCHandler;
@@ -111,7 +111,7 @@ public void run() {
       }
       Throwable errorThrowable = null;
       String error = null;
-      Pair<Message, CellScanner> resultPair = null;
+      Pair<Message, ExtendedCellScanner> resultPair = null;
       RpcServer.CurCall.set(call);
       final Span ipcServerSpan = new IpcServerSpanBuilder(call).build();
       try (Scope ignored1 = ipcServerSpan.makeCurrent()) {
@@ -156,7 +156,7 @@ public void run() {
       call.cleanup();
       // Set the response
       Message param = resultPair != null ? resultPair.getFirst() : null;
-      CellScanner cells = resultPair != null ? resultPair.getSecond() : null;
+      ExtendedCellScanner cells = resultPair != null ? resultPair.getSecond() : null;
       call.setResponse(param, cells, errorThrowable, error);
       call.sendResponseIfReady();
       // don't touch `span` here because its status and `end()` are managed in `call#setResponse()`
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/NettyServerCall.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/NettyServerCall.java
index 4f0540da80a7..62cac989d8a7 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/NettyServerCall.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/NettyServerCall.java
@@ -19,7 +19,7 @@
 
 import java.io.IOException;
 import java.net.InetAddress;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.io.ByteBuffAllocator;
 import org.apache.hadoop.hbase.ipc.RpcServer.CallCleanup;
 import org.apache.yetus.audience.InterfaceAudience;
@@ -39,7 +39,7 @@
 class NettyServerCall extends ServerCall<NettyServerRpcConnection> {
 
   NettyServerCall(int id, BlockingService service, MethodDescriptor md, RequestHeader header,
-    Message param, CellScanner cellScanner, NettyServerRpcConnection connection, long size,
+    Message param, ExtendedCellScanner cellScanner, NettyServerRpcConnection connection, long size,
     InetAddress remoteAddress, long receiveTime, int timeout, ByteBuffAllocator bbAllocator,
     CellBlockBuilder cellBlockBuilder, CallCleanup reqCleanup) {
     super(id, service, md, header, param, cellScanner, connection, size, remoteAddress, receiveTime,
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/NettyServerRpcConnection.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/NettyServerRpcConnection.java
index f52357539dec..f63b8d2730f7 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/NettyServerRpcConnection.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/NettyServerRpcConnection.java
@@ -20,7 +20,7 @@
 import java.io.IOException;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.ipc.RpcServer.CallCleanup;
 import org.apache.hadoop.hbase.nio.ByteBuff;
 import org.apache.hadoop.hbase.nio.SingleByteBuff;
@@ -107,7 +107,7 @@ public boolean isConnectionOpen() {
 
   @Override
   public NettyServerCall createCall(int id, final BlockingService service,
-    final MethodDescriptor md, RequestHeader header, Message param, CellScanner cellScanner,
+    final MethodDescriptor md, RequestHeader header, Message param, ExtendedCellScanner cellScanner,
     long size, final InetAddress remoteAddress, int timeout, CallCleanup reqCleanup) {
     return new NettyServerCall(id, service, md, header, param, cellScanner, this, size,
       remoteAddress, EnvironmentEdgeManager.currentTime(), timeout, this.rpcServer.bbAllocator,
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RpcCall.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RpcCall.java
index 2d06aa7c47af..804d7b32bb42 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RpcCall.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RpcCall.java
@@ -20,7 +20,7 @@
 import java.io.IOException;
 import java.util.Map;
 import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.yetus.audience.InterfaceStability;
@@ -48,7 +48,7 @@ public interface RpcCall extends RpcCallContext {
   Message getParam();
 
   /** Returns The CellScanner that can carry input and result payload. */
-  CellScanner getCellScanner();
+  ExtendedCellScanner getCellScanner();
 
   /** Returns The timestamp when the call is constructed. */
   long getReceiveTime();
@@ -117,7 +117,8 @@ public interface RpcCall extends RpcCallContext {
    * @param errorThrowable The error Throwable resulting from the call.
    * @param error          Extra error message.
    */
-  void setResponse(Message param, CellScanner cells, Throwable errorThrowable, String error);
+  void setResponse(Message param, ExtendedCellScanner cells, Throwable errorThrowable,
+    String error);
 
   /**
    * Send the response of this RPC call. Implementation provides the underlying facility
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RpcServer.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RpcServer.java
index a84d132a0132..4ff1a0b54828 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RpcServer.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RpcServer.java
@@ -38,6 +38,7 @@
 import org.apache.hadoop.hbase.CallQueueTooBigException;
 import org.apache.hadoop.hbase.CellScanner;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.Server;
 import org.apache.hadoop.hbase.conf.ConfigurationObserver;
@@ -428,7 +429,7 @@ public void setSecretManager(SecretManager<? extends TokenIdentifier> secretMana
    * the protobuf response.
    */
   @Override
-  public Pair<Message, CellScanner> call(RpcCall call, MonitoredRPCHandler status)
+  public Pair<Message, ExtendedCellScanner> call(RpcCall call, MonitoredRPCHandler status)
     throws IOException {
     try {
       MethodDescriptor md = call.getMethod();
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RpcServerInterface.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RpcServerInterface.java
index 2c0dd1cc2b0e..9bf5fc3817dc 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RpcServerInterface.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RpcServerInterface.java
@@ -20,7 +20,7 @@
 import java.io.IOException;
 import java.net.InetSocketAddress;
 import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.io.ByteBuffAllocator;
 import org.apache.hadoop.hbase.monitoring.MonitoredRPCHandler;
 import org.apache.hadoop.hbase.namequeues.NamedQueueRecorder;
@@ -45,7 +45,8 @@ public interface RpcServerInterface {
 
   InetSocketAddress getListenerAddress();
 
-  Pair<Message, CellScanner> call(RpcCall call, MonitoredRPCHandler status) throws IOException;
+  Pair<Message, ExtendedCellScanner> call(RpcCall call, MonitoredRPCHandler status)
+    throws IOException;
 
   void setErrorHandler(HBaseRPCErrorHandler handler);
 
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/ServerCall.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/ServerCall.java
index 25d153c068aa..c2c6b4d063c2 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/ServerCall.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/ServerCall.java
@@ -30,8 +30,8 @@
 import java.util.Map;
 import java.util.Optional;
 import java.util.concurrent.atomic.AtomicInteger;
-import org.apache.hadoop.hbase.CellScanner;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HBaseServerException;
 import org.apache.hadoop.hbase.exceptions.RegionMovedException;
 import org.apache.hadoop.hbase.io.ByteBuffAllocator;
@@ -72,7 +72,7 @@ public abstract class ServerCall<T extends ServerRpcConnection> implements RpcCa
   protected final RequestHeader header;
   protected Message param; // the parameter passed
   // Optional cell data passed outside of protobufs.
-  protected final CellScanner cellScanner;
+  protected final ExtendedCellScanner cellScanner;
   protected final T connection; // connection to client
   protected final long receiveTime; // the time received when response is null
   // the time served when response is not null
@@ -120,8 +120,8 @@ public abstract class ServerCall<T extends ServerRpcConnection> implements RpcCa
   @edu.umd.cs.findbugs.annotations.SuppressWarnings(value = "NP_NULL_ON_SOME_PATH",
       justification = "Can't figure why this complaint is happening... see below")
   ServerCall(int id, BlockingService service, MethodDescriptor md, RequestHeader header,
-    Message param, CellScanner cellScanner, T connection, long size, InetAddress remoteAddress,
-    long receiveTime, int timeout, ByteBuffAllocator byteBuffAllocator,
+    Message param, ExtendedCellScanner cellScanner, T connection, long size,
+    InetAddress remoteAddress, long receiveTime, int timeout, ByteBuffAllocator byteBuffAllocator,
     CellBlockBuilder cellBlockBuilder, CallCleanup reqCleanup) {
     this.id = id;
     this.service = service;
@@ -273,7 +273,7 @@ public String toShortString() {
   }
 
   @Override
-  public synchronized void setResponse(Message m, final CellScanner cells, Throwable t,
+  public synchronized void setResponse(Message m, final ExtendedCellScanner cells, Throwable t,
     String errorMsg) {
     if (this.isError) {
       return;
@@ -544,7 +544,7 @@ public Message getParam() {
   }
 
   @Override
-  public CellScanner getCellScanner() {
+  public ExtendedCellScanner getCellScanner() {
     return cellScanner;
   }
 
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/ServerRpcConnection.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/ServerRpcConnection.java
index 31f46f30c382..c17a8da90416 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/ServerRpcConnection.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/ServerRpcConnection.java
@@ -39,8 +39,8 @@
 import org.apache.commons.crypto.cipher.CryptoCipherFactory;
 import org.apache.commons.crypto.random.CryptoRandom;
 import org.apache.commons.crypto.random.CryptoRandomFactory;
-import org.apache.hadoop.hbase.CellScanner;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.client.ConnectionRegistryEndpoint;
 import org.apache.hadoop.hbase.client.VersionInfoUtil;
 import org.apache.hadoop.hbase.codec.Codec;
@@ -588,7 +588,7 @@ protected void processRequest(ByteBuff buf) throws IOException, InterruptedExcep
       }
       MethodDescriptor md = null;
       Message param = null;
-      CellScanner cellScanner = null;
+      ExtendedCellScanner cellScanner = null;
       try {
         if (header.hasRequestParam() && header.getRequestParam()) {
           md = this.service.getDescriptorForType().findMethodByName(header.getMethodName());
@@ -816,7 +816,7 @@ boolean isSimpleAuthentication() {
   public abstract boolean isConnectionOpen();
 
   public abstract ServerCall<?> createCall(int id, BlockingService service, MethodDescriptor md,
-    RequestHeader header, Message param, CellScanner cellScanner, long size,
+    RequestHeader header, Message param, ExtendedCellScanner cellScanner, long size,
     InetAddress remoteAddress, int timeout, CallCleanup reqCleanup);
 
   private static class ByteBuffByteInput extends ByteInput {
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/SimpleServerCall.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/SimpleServerCall.java
index 5c5e9102115c..aa6e2b7b4aca 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/SimpleServerCall.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/SimpleServerCall.java
@@ -19,7 +19,7 @@
 
 import java.io.IOException;
 import java.net.InetAddress;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.io.ByteBuffAllocator;
 import org.apache.hadoop.hbase.ipc.RpcServer.CallCleanup;
 import org.apache.yetus.audience.InterfaceAudience;
@@ -43,7 +43,7 @@ class SimpleServerCall extends ServerCall<SimpleServerRpcConnection> {
   @edu.umd.cs.findbugs.annotations.SuppressWarnings(value = "NP_NULL_ON_SOME_PATH",
       justification = "Can't figure why this complaint is happening... see below")
   SimpleServerCall(int id, final BlockingService service, final MethodDescriptor md,
-    RequestHeader header, Message param, CellScanner cellScanner,
+    RequestHeader header, Message param, ExtendedCellScanner cellScanner,
     SimpleServerRpcConnection connection, long size, final InetAddress remoteAddress,
     long receiveTime, int timeout, ByteBuffAllocator bbAllocator, CellBlockBuilder cellBlockBuilder,
     CallCleanup reqCleanup, SimpleRpcServerResponder responder) {
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/SimpleServerRpcConnection.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/SimpleServerRpcConnection.java
index 1b28c19b4306..e8619b2eb7f5 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/SimpleServerRpcConnection.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/SimpleServerRpcConnection.java
@@ -30,8 +30,8 @@
 import java.util.concurrent.atomic.LongAdder;
 import java.util.concurrent.locks.Lock;
 import java.util.concurrent.locks.ReentrantLock;
-import org.apache.hadoop.hbase.CellScanner;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.client.VersionInfoUtil;
 import org.apache.hadoop.hbase.exceptions.RequestTooBigException;
 import org.apache.hadoop.hbase.ipc.RpcServer.CallCleanup;
@@ -456,7 +456,7 @@ public boolean isConnectionOpen() {
 
   @Override
   public SimpleServerCall createCall(int id, BlockingService service, MethodDescriptor md,
-    RequestHeader header, Message param, CellScanner cellScanner, long size,
+    RequestHeader header, Message param, ExtendedCellScanner cellScanner, long size,
     InetAddress remoteAddress, int timeout, CallCleanup reqCleanup) {
     return new SimpleServerCall(id, service, md, header, param, cellScanner, this, size,
       remoteAddress, EnvironmentEdgeManager.currentTime(), timeout, this.rpcServer.bbAllocator,
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/mob/MobUtils.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/mob/MobUtils.java
index 2fadc83340ed..66160dd4aa64 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/mob/MobUtils.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/mob/MobUtils.java
@@ -120,7 +120,7 @@ public static Date parseDate(String dateString) throws ParseException {
    * @param cell The current cell.
    * @return True if the cell has a mob reference tag, false if it doesn't.
    */
-  public static boolean isMobReferenceCell(Cell cell) {
+  public static boolean isMobReferenceCell(ExtendedCell cell) {
     if (cell.getTagsLength() > 0) {
       Optional<Tag> tag = PrivateCellUtil.getTag(cell, TagType.MOB_REFERENCE_TAG_TYPE);
       if (tag.isPresent()) {
@@ -135,7 +135,7 @@ public static boolean isMobReferenceCell(Cell cell) {
    * @param cell The current cell.
    * @return The table name tag.
    */
-  private static Optional<Tag> getTableNameTag(Cell cell) {
+  private static Optional<Tag> getTableNameTag(ExtendedCell cell) {
     Optional<Tag> tag = Optional.empty();
     if (cell.getTagsLength() > 0) {
       tag = PrivateCellUtil.getTag(cell, TagType.MOB_TABLE_NAME_TAG_TYPE);
@@ -148,7 +148,7 @@ private static Optional<Tag> getTableNameTag(Cell cell) {
    * @param cell to extract tag from
    * @return table name as a string. empty if the tag is not found.
    */
-  public static Optional<String> getTableNameString(Cell cell) {
+  public static Optional<String> getTableNameString(ExtendedCell cell) {
     Optional<Tag> tag = getTableNameTag(cell);
     Optional<String> name = Optional.empty();
     if (tag.isPresent()) {
@@ -162,7 +162,7 @@ public static Optional<String> getTableNameString(Cell cell) {
    * @param cell to extract tag from
    * @return name of table as a TableName. empty if the tag is not found.
    */
-  public static Optional<TableName> getTableName(Cell cell) {
+  public static Optional<TableName> getTableName(ExtendedCell cell) {
     Optional<Tag> maybe = getTableNameTag(cell);
     Optional<TableName> name = Optional.empty();
     if (maybe.isPresent()) {
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/protobuf/ReplicationProtobufUtil.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/protobuf/ReplicationProtobufUtil.java
index 6754fdef08ab..0b1736e21a46 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/protobuf/ReplicationProtobufUtil.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/protobuf/ReplicationProtobufUtil.java
@@ -24,10 +24,11 @@
 import java.util.concurrent.CompletableFuture;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCell;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.client.AsyncRegionServerAdmin;
-import org.apache.hadoop.hbase.io.SizedCellScanner;
+import org.apache.hadoop.hbase.io.SizedExtendedCellScanner;
 import org.apache.hadoop.hbase.regionserver.wal.WALCellCodec;
 import org.apache.hadoop.hbase.util.Pair;
 import org.apache.hadoop.hbase.wal.WAL.Entry;
@@ -56,8 +57,8 @@ public class ReplicationProtobufUtil {
   public static CompletableFuture<ReplicateWALEntryResponse> replicateWALEntry(
     AsyncRegionServerAdmin admin, Entry[] entries, String replicationClusterId,
     Path sourceBaseNamespaceDir, Path sourceHFileArchiveDir, int timeout) {
-    Pair<ReplicateWALEntryRequest, CellScanner> p = buildReplicateWALEntryRequest(entries, null,
-      replicationClusterId, sourceBaseNamespaceDir, sourceHFileArchiveDir);
+    Pair<ReplicateWALEntryRequest, ExtendedCellScanner> p = buildReplicateWALEntryRequest(entries,
+      null, replicationClusterId, sourceBaseNamespaceDir, sourceHFileArchiveDir);
     return admin.replicateWALEntry(p.getFirst(), p.getSecond(), timeout);
   }
 
@@ -66,7 +67,7 @@ public static CompletableFuture<ReplicateWALEntryResponse> replicateWALEntry(
    * @param entries the WAL entries to be replicated
    * @return a pair of ReplicateWALEntryRequest and a CellScanner over all the WALEdit values found.
    */
-  public static Pair<ReplicateWALEntryRequest, CellScanner>
+  public static Pair<ReplicateWALEntryRequest, ExtendedCellScanner>
     buildReplicateWALEntryRequest(final Entry[] entries) {
     return buildReplicateWALEntryRequest(entries, null, null, null, null);
   }
@@ -81,11 +82,11 @@ public static CompletableFuture<ReplicateWALEntryResponse> replicateWALEntry(
    * @param sourceHFileArchiveDir  Path to the source cluster hfile archive directory
    * @return a pair of ReplicateWALEntryRequest and a CellScanner over all the WALEdit values found.
    */
-  public static Pair<ReplicateWALEntryRequest, CellScanner> buildReplicateWALEntryRequest(
+  public static Pair<ReplicateWALEntryRequest, ExtendedCellScanner> buildReplicateWALEntryRequest(
     final Entry[] entries, byte[] encodedRegionName, String replicationClusterId,
     Path sourceBaseNamespaceDir, Path sourceHFileArchiveDir) {
     // Accumulate all the Cells seen in here.
-    List<List<? extends Cell>> allCells = new ArrayList<>(entries.length);
+    List<List<? extends ExtendedCell>> allCells = new ArrayList<>(entries.length);
     int size = 0;
     WALEntry.Builder entryBuilder = WALEntry.newBuilder();
     ReplicateWALEntryRequest.Builder builder = ReplicateWALEntryRequest.newBuilder();
@@ -104,7 +105,8 @@ public static Pair<ReplicateWALEntryRequest, CellScanner> buildReplicateWALEntry
       }
       entryBuilder.setKey(keyBuilder.build());
       WALEdit edit = entry.getEdit();
-      List<Cell> cells = edit.getCells();
+      // TODO: avoid this cast
+      List<ExtendedCell> cells = (List) edit.getCells();
       // Add up the size. It is used later serializing out the kvs.
       for (Cell cell : cells) {
         size += PrivateCellUtil.estimatedSerializedSizeOf(cell);
@@ -130,21 +132,24 @@ public static Pair<ReplicateWALEntryRequest, CellScanner> buildReplicateWALEntry
   }
 
   /** Returns <code>cells</code> packaged as a CellScanner */
-  static CellScanner getCellScanner(final List<List<? extends Cell>> cells, final int size) {
-    return new SizedCellScanner() {
-      private final Iterator<List<? extends Cell>> entries = cells.iterator();
-      private Iterator<? extends Cell> currentIterator = null;
-      private Cell currentCell;
+  static ExtendedCellScanner getCellScanner(final List<List<? extends ExtendedCell>> cells,
+    final int size) {
+    return new SizedExtendedCellScanner() {
+      private final Iterator<List<? extends ExtendedCell>> entries = cells.iterator();
+      private Iterator<? extends ExtendedCell> currentIterator = null;
+      private ExtendedCell currentCell;
 
       @Override
-      public Cell current() {
+      public ExtendedCell current() {
         return this.currentCell;
       }
 
       @Override
       public boolean advance() {
         if (this.currentIterator == null) {
-          if (!this.entries.hasNext()) return false;
+          if (!this.entries.hasNext()) {
+            return false;
+          }
           this.currentIterator = this.entries.next().iterator();
         }
         if (this.currentIterator.hasNext()) {
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegion.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegion.java
index 2792ab2754cd..68f5356f5549 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegion.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegion.java
@@ -112,6 +112,7 @@
 import org.apache.hadoop.hbase.client.Increment;
 import org.apache.hadoop.hbase.client.IsolationLevel;
 import org.apache.hadoop.hbase.client.Mutation;
+import org.apache.hadoop.hbase.client.PackagePrivateFieldAccessor;
 import org.apache.hadoop.hbase.client.Put;
 import org.apache.hadoop.hbase.client.RegionInfo;
 import org.apache.hadoop.hbase.client.RegionReplicaUtil;
@@ -3512,7 +3513,7 @@ protected void checkAndPrepareMutation(int index, long timestamp) throws IOExcep
           // store the family map reference to allow for mutations
           // we know that in mutation, only ExtendedCells are allow so here we do a fake cast, to
           // simplify later logic
-          familyCellMaps[index] = (Map) mutation.getFamilyCellMap();
+          familyCellMaps[index] = PackagePrivateFieldAccessor.getExtendedFamilyCellMap(mutation);
         }
 
         // store durability for the batch (highest durability of all operations in the batch)
@@ -4063,7 +4064,8 @@ private Map<byte[], List<ExtendedCell>> reckonDeltas(Mutation mutation,
       assert mutation instanceof Increment || mutation instanceof Append;
       Map<byte[], List<ExtendedCell>> ret = new TreeMap<>(Bytes.BYTES_COMPARATOR);
       // Process a Store/family at a time.
-      for (Map.Entry<byte[], List<Cell>> entry : mutation.getFamilyCellMap().entrySet()) {
+      for (Map.Entry<byte[], List<ExtendedCell>> entry : PackagePrivateFieldAccessor
+        .getExtendedFamilyCellMap(mutation).entrySet()) {
         final byte[] columnFamilyName = entry.getKey();
         List<ExtendedCell> deltas = (List) entry.getValue();
         // Reckon for the Store what to apply to WAL and MemStore.
@@ -4184,9 +4186,9 @@ private List<ExtendedCell> reckonDeltasByStore(HStore store, Mutation mutation,
       return cellPairs.stream().map(Pair::getSecond).collect(Collectors.toList());
     }
 
-    private static ExtendedCell reckonDelta(final Cell delta, final Cell currentCell,
-      final byte[] columnFamily, final long now, Mutation mutation, Function<Cell, byte[]> supplier)
-      throws IOException {
+    private static ExtendedCell reckonDelta(final ExtendedCell delta,
+      final ExtendedCell currentCell, final byte[] columnFamily, final long now, Mutation mutation,
+      Function<ExtendedCell, byte[]> supplier) throws IOException {
       // Forward any tags found on the delta.
       List<Tag> tags = TagUtil.carryForwardTags(delta);
       if (currentCell != null) {
@@ -4204,7 +4206,6 @@ private static ExtendedCell reckonDelta(final Cell delta, final Cell currentCell
       } else {
         tags = TagUtil.carryForwardTTLTag(tags, mutation.getTTL());
         PrivateCellUtil.updateLatestStamp(delta, now);
-        assert delta instanceof ExtendedCell;
         ExtendedCell deltaCell = (ExtendedCell) delta;
         return CollectionUtils.isEmpty(tags)
           ? deltaCell
@@ -4522,7 +4523,8 @@ private void checkAndMergeCPMutations(final MiniBatchOperationInProgress<Mutatio
 
           // Returned mutations from coprocessor correspond to the Mutation at index i. We can
           // directly add the cells from those mutations to the familyMaps of this mutation.
-          Map<byte[], List<ExtendedCell>> cpFamilyMap = (Map) cpMutation.getFamilyCellMap();
+          Map<byte[], List<ExtendedCell>> cpFamilyMap =
+            PackagePrivateFieldAccessor.getExtendedFamilyCellMap(cpMutation);
           region.rewriteCellTags(cpFamilyMap, mutation);
           // will get added to the memStore later
           mergeFamilyMaps(familyCellMaps[i], cpFamilyMap);
@@ -5094,14 +5096,16 @@ private CheckAndMutateResult checkAndMutateInternal(CheckAndMutate checkAndMutat
           byte[] byteTs = Bytes.toBytes(ts);
           if (mutation != null) {
             if (mutation instanceof Put) {
-              updateCellTimestamps((Iterable) mutation.getFamilyCellMap().values(), byteTs);
+              updateCellTimestamps(
+                PackagePrivateFieldAccessor.getExtendedFamilyCellMap(mutation).values(), byteTs);
             }
             // And else 'delete' is not needed since it already does a second get, and sets the
             // timestamp from get (see prepareDeleteTimestamps).
           } else {
             for (Mutation m : rowMutations.getMutations()) {
               if (m instanceof Put) {
-                updateCellTimestamps((Iterable) m.getFamilyCellMap().values(), byteTs);
+                updateCellTimestamps(
+                  PackagePrivateFieldAccessor.getExtendedFamilyCellMap(m).values(), byteTs);
               }
             }
             // And else 'delete' is not needed since it already does a second get, and sets the
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/MobReferenceOnlyFilter.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/MobReferenceOnlyFilter.java
index 4efc29dea100..f3191c6374d8 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/MobReferenceOnlyFilter.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/MobReferenceOnlyFilter.java
@@ -18,6 +18,7 @@
 package org.apache.hadoop.hbase.regionserver;
 
 import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.filter.FilterBase;
 import org.apache.hadoop.hbase.mob.MobUtils;
 import org.apache.yetus.audience.InterfaceAudience;
@@ -30,9 +31,9 @@ class MobReferenceOnlyFilter extends FilterBase {
 
   @Override
   public ReturnCode filterCell(final Cell cell) {
-    if (null != cell) {
+    if (null != cell && cell instanceof ExtendedCell) {
       // If a cell with a mob reference tag, it's included.
-      if (MobUtils.isMobReferenceCell(cell)) {
+      if (MobUtils.isMobReferenceCell((ExtendedCell) cell)) {
         return ReturnCode.INCLUDE;
       }
     }
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/RSRpcServices.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/RSRpcServices.java
index 66c97fb9401f..47011c5b5520 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/RSRpcServices.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/RSRpcServices.java
@@ -47,11 +47,12 @@
 import org.apache.hadoop.hbase.CacheEvictionStats;
 import org.apache.hadoop.hbase.CacheEvictionStatsBuilder;
 import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.CellScannable;
 import org.apache.hadoop.hbase.CellScanner;
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
 import org.apache.hadoop.hbase.DroppedSnapshotException;
+import org.apache.hadoop.hbase.ExtendedCellScannable;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HBaseIOException;
 import org.apache.hadoop.hbase.HBaseRpcServicesBase;
 import org.apache.hadoop.hbase.HConstants;
@@ -72,6 +73,7 @@
 import org.apache.hadoop.hbase.client.Increment;
 import org.apache.hadoop.hbase.client.Mutation;
 import org.apache.hadoop.hbase.client.OperationWithAttributes;
+import org.apache.hadoop.hbase.client.PackagePrivateFieldAccessor;
 import org.apache.hadoop.hbase.client.Put;
 import org.apache.hadoop.hbase.client.RegionInfo;
 import org.apache.hadoop.hbase.client.RegionReplicaUtil;
@@ -581,7 +583,7 @@ private void addResults(ScanResponse.Builder builder, List<Result> results,
         builder.addCellsPerResult(res.size());
         builder.addPartialFlagPerResult(res.mayHaveMoreCellsInRow());
       }
-      controller.setCellScanner(CellUtil.createCellScanner(results));
+      controller.setCellScanner(PrivateCellUtil.createExtendedCellScanner(results));
     } else {
       for (Result res : results) {
         ClientProtos.Result pbr = ProtobufUtil.toResult(res);
@@ -725,10 +727,10 @@ private Result increment(final HRegion region, final OperationQuota quota,
    * @param context       the current RpcCallContext
    * @return Return the <code>cellScanner</code> passed
    */
-  private List<CellScannable> doNonAtomicRegionMutation(final HRegion region,
+  private List<ExtendedCellScannable> doNonAtomicRegionMutation(final HRegion region,
     final OperationQuota quota, final RegionAction actions, final CellScanner cellScanner,
-    final RegionActionResult.Builder builder, List<CellScannable> cellsToReturn, long nonceGroup,
-    final RegionScannersCloseCallBack closeCallBack, RpcCallContext context,
+    final RegionActionResult.Builder builder, List<ExtendedCellScannable> cellsToReturn,
+    long nonceGroup, final RegionScannersCloseCallBack closeCallBack, RpcCallContext context,
     ActivePolicyEnforcement spaceQuotaEnforcement) {
     // Gather up CONTIGUOUS Puts and Deletes in this mutations List. Idea is that rather than do
     // one at a time, we instead pass them in batch. Be aware that the corresponding
@@ -2053,9 +2055,9 @@ public WarmupRegionResponse warmupRegion(final RpcController controller,
     return response;
   }
 
-  private CellScanner getAndReset(RpcController controller) {
+  private ExtendedCellScanner getAndReset(RpcController controller) {
     HBaseRpcController hrc = (HBaseRpcController) controller;
-    CellScanner cells = hrc.cellScanner();
+    ExtendedCellScanner cells = hrc.cellScanner();
     hrc.setCellScanner(null);
     return cells;
   }
@@ -2498,8 +2500,8 @@ public GetResponse get(final RpcController controller, final GetRequest request)
             && VersionInfoUtil.hasMinimumVersion(context.getClientVersionInfo(), 1, 3)
         ) {
           pbr = ProtobufUtil.toResultNoData(r);
-          ((HBaseRpcController) controller)
-            .setCellScanner(CellUtil.createCellScanner(r.rawCells()));
+          ((HBaseRpcController) controller).setCellScanner(PrivateCellUtil
+            .createExtendedCellScanner(PackagePrivateFieldAccessor.getExtendedRawCells(r)));
           addSize(context, r);
         } else {
           pbr = ProtobufUtil.toResult(r);
@@ -2648,10 +2650,7 @@ public MultiResponse multi(final RpcController rpcc, final MultiRequest request)
     // rpc controller is how we bring in data via the back door; it is unprotobuf'ed data.
     // It is also the conduit via which we pass back data.
     HBaseRpcController controller = (HBaseRpcController) rpcc;
-    CellScanner cellScanner = controller != null ? controller.cellScanner() : null;
-    if (controller != null) {
-      controller.setCellScanner(null);
-    }
+    CellScanner cellScanner = controller != null ? getAndReset(controller) : null;
 
     long nonceGroup = request.hasNonceGroup() ? request.getNonceGroup() : HConstants.NO_NONCE;
 
@@ -2732,7 +2731,7 @@ public MultiResponse multi(final RpcController rpcc, final MultiRequest request)
     }
 
     // this will contain all the cells that we need to return. It's created later, if needed.
-    List<CellScannable> cellsToReturn = null;
+    List<ExtendedCellScannable> cellsToReturn = null;
     RegionScannersCloseCallBack closeCallBack = null;
     RpcCallContext context = RpcServer.getCurrentCall().orElse(null);
     Map<RegionSpecifier, ClientProtos.RegionLoadStats> regionStats =
@@ -2858,7 +2857,7 @@ public MultiResponse multi(final RpcController rpcc, final MultiRequest request)
     }
     // Load the controller with the Cells to return.
     if (cellsToReturn != null && !cellsToReturn.isEmpty() && controller != null) {
-      controller.setCellScanner(CellUtil.createCellScanner(cellsToReturn));
+      controller.setCellScanner(PrivateCellUtil.createExtendedCellScanner(cellsToReturn));
     }
 
     MultiRegionLoadStats.Builder builder = MultiRegionLoadStats.newBuilder();
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/ReversedMobStoreScanner.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/ReversedMobStoreScanner.java
index 505cd5dedcee..81a4cc467f98 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/ReversedMobStoreScanner.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/ReversedMobStoreScanner.java
@@ -75,7 +75,7 @@ public boolean next(List<Cell> outResult, ScannerContext ctx) throws IOException
       for (int i = 0; i < outResult.size(); i++) {
         Cell cell = outResult.get(i);
         assert cell instanceof ExtendedCell;
-        if (MobUtils.isMobReferenceCell(cell)) {
+        if (MobUtils.isMobReferenceCell((ExtendedCell) cell)) {
           MobCell mobCell = mobStore.resolve((ExtendedCell) cell, cacheMobBlocks, readPt,
             readEmptyValueOnMobCellMiss);
           mobKVCount++;
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/AsyncProtobufLogWriter.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/AsyncProtobufLogWriter.java
index bb874a001d2f..dff2052efe78 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/AsyncProtobufLogWriter.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/AsyncProtobufLogWriter.java
@@ -31,6 +31,7 @@
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.exceptions.TimeoutIOException;
 import org.apache.hadoop.hbase.io.ByteBufferWriter;
@@ -139,7 +140,7 @@ public void append(Entry entry) {
     }
     try {
       for (Cell cell : entry.getEdit().getCells()) {
-        cellEncoder.write(cell);
+        cellEncoder.write((ExtendedCell) cell);
       }
     } catch (IOException e) {
       throw new AssertionError("should not happen", e);
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/ProtobufLogWriter.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/ProtobufLogWriter.java
index 52317949cc83..6e6727db085d 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/ProtobufLogWriter.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/ProtobufLogWriter.java
@@ -26,6 +26,7 @@
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.StreamCapabilities;
 import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.io.asyncfs.monitor.StreamSlowMonitor;
 import org.apache.hadoop.hbase.util.AtomicUtils;
 import org.apache.hadoop.hbase.util.CommonFSUtils;
@@ -58,7 +59,7 @@ public void append(Entry entry) throws IOException {
       .writeDelimitedTo(output);
     for (Cell cell : entry.getEdit().getCells()) {
       // cellEncoder must assume little about the stream, since we write PB and cells in turn.
-      cellEncoder.write(cell);
+      cellEncoder.write((ExtendedCell) cell);
     }
     length.set(output.getPos());
   }
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/SecureWALCellCodec.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/SecureWALCellCodec.java
index 754368f73f3c..ec47283469c9 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/SecureWALCellCodec.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/SecureWALCellCodec.java
@@ -24,7 +24,6 @@
 import java.io.OutputStream;
 import org.apache.commons.io.IOUtils;
 import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.KeyValueUtil;
@@ -79,7 +78,7 @@ public EncryptedKvDecoder(InputStream in, Decryptor decryptor) {
     }
 
     @Override
-    protected Cell parseCell() throws IOException {
+    protected ExtendedCell parseCell() throws IOException {
       if (this.decryptor == null) {
         return super.parseCell();
       }
@@ -174,7 +173,7 @@ public EncryptedKvEncoder(OutputStream os, Encryptor encryptor) {
     }
 
     @Override
-    public void write(Cell c) throws IOException {
+    public void write(ExtendedCell c) throws IOException {
       if (encryptor == null) {
         super.write(c);
         return;
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/WALCellCodec.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/WALCellCodec.java
index e6a20b0d0206..87154a62066c 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/WALCellCodec.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/WALCellCodec.java
@@ -233,9 +233,7 @@ public CompressedKvEncoder(OutputStream out, CompressionContext compression) {
     }
 
     @Override
-    public void write(Cell c) throws IOException {
-      assert c instanceof ExtendedCell;
-      ExtendedCell cell = (ExtendedCell) c;
+    public void write(ExtendedCell cell) throws IOException {
       // We first write the KeyValue infrastructure as VInts.
       StreamUtils.writeRawVInt32(out, KeyValueUtil.keyLength(cell));
       StreamUtils.writeRawVInt32(out, cell.getValueLength());
@@ -290,7 +288,7 @@ public CompressedKvDecoder(InputStream in, CompressionContext compression) {
     }
 
     @Override
-    protected Cell parseCell() throws IOException {
+    protected ExtendedCell parseCell() throws IOException {
       int keylength = StreamUtils.readRawVarint32(in);
       int vlength = StreamUtils.readRawVarint32(in);
       int tagsLength = StreamUtils.readRawVarint32(in);
@@ -396,7 +394,7 @@ public EnsureKvEncoder(OutputStream out) {
     }
 
     @Override
-    public void write(Cell cell) throws IOException {
+    public void write(ExtendedCell cell) throws IOException {
       checkFlushed();
       // Make sure to write tags into WAL
       ByteBufferUtils.putInt(this.out, KeyValueUtil.getSerializedSize(cell, true));
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/replication/regionserver/ReplaySyncReplicationWALCallable.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/replication/regionserver/ReplaySyncReplicationWALCallable.java
index a60186c13dc7..427fe80b0c36 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/replication/regionserver/ReplaySyncReplicationWALCallable.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/replication/regionserver/ReplaySyncReplicationWALCallable.java
@@ -23,8 +23,8 @@
 import java.util.List;
 import java.util.concurrent.locks.Lock;
 import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.hbase.CellScanner;
 import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.executor.EventType;
 import org.apache.hadoop.hbase.procedure2.BaseRSProcedureCallable;
 import org.apache.hadoop.hbase.protobuf.ReplicationProtobufUtil;
@@ -106,8 +106,9 @@ private void replayWAL(String wal) throws IOException {
     try {
       List<Entry> entries = readWALEntries(reader, wal);
       while (!entries.isEmpty()) {
-        Pair<AdminProtos.ReplicateWALEntryRequest, CellScanner> pair = ReplicationProtobufUtil
-          .buildReplicateWALEntryRequest(entries.toArray(new Entry[entries.size()]));
+        Pair<AdminProtos.ReplicateWALEntryRequest, ExtendedCellScanner> pair =
+          ReplicationProtobufUtil
+            .buildReplicateWALEntryRequest(entries.toArray(new Entry[entries.size()]));
         ReplicateWALEntryRequest request = pair.getFirst();
         rs.getReplicationSinkService().replicateLogEntries(request.getEntryList(), pair.getSecond(),
           request.getReplicationClusterId(), request.getSourceBaseNamespaceDirPath(),
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/security/access/AccessController.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/security/access/AccessController.java
index d0c19d7cfcd5..f0158f299f22 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/security/access/AccessController.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/security/access/AccessController.java
@@ -35,13 +35,13 @@
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.ArrayBackedTag;
 import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.CellScanner;
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.CompareOperator;
 import org.apache.hadoop.hbase.CompoundConfiguration;
 import org.apache.hadoop.hbase.CoprocessorEnvironment;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
 import org.apache.hadoop.hbase.ExtendedCell;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.KeyValue;
@@ -644,7 +644,7 @@ private void checkForReservedTagPresence(User user, Mutation m) throws IOExcepti
     if (m.getAttribute(TAG_CHECK_PASSED) != null) {
       return;
     }
-    for (CellScanner cellScanner = m.cellScanner(); cellScanner.advance();) {
+    for (ExtendedCellScanner cellScanner = m.cellScanner(); cellScanner.advance();) {
       Iterator<Tag> tagsItr = PrivateCellUtil.tagsIterator(cellScanner.current());
       while (tagsItr.hasNext()) {
         if (tagsItr.next().getType() == PermissionStorage.ACL_TAG_TYPE) {
@@ -1732,8 +1732,9 @@ private Cell createNewCellWithTags(Mutation mutation, Cell oldCell, Cell newCell
     // there is no need to rewrite them again. Just extract non-acl tags of newCell if we need to
     // add a new acl tag for the cell. Actually, oldCell is useless here.
     List<Tag> tags = Lists.newArrayList();
-    if (newCell != null) {
-      Iterator<Tag> tagIterator = PrivateCellUtil.tagsIterator(newCell);
+    ExtendedCell newExtendedCell = (ExtendedCell) newCell;
+    if (newExtendedCell != null) {
+      Iterator<Tag> tagIterator = PrivateCellUtil.tagsIterator(newExtendedCell);
       while (tagIterator.hasNext()) {
         Tag tag = tagIterator.next();
         if (tag.getType() != PermissionStorage.ACL_TAG_TYPE) {
@@ -1750,8 +1751,7 @@ private Cell createNewCellWithTags(Mutation mutation, Cell oldCell, Cell newCell
     // We have checked the ACL tag of mutation is not null.
     // So that the tags could not be empty.
     tags.add(new ArrayBackedTag(PermissionStorage.ACL_TAG_TYPE, mutation.getACL()));
-    assert newCell instanceof ExtendedCell;
-    return PrivateCellUtil.createCell((ExtendedCell) newCell, tags);
+    return PrivateCellUtil.createCell(newExtendedCell, tags);
   }
 
   @Override
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/security/access/AuthManager.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/security/access/AuthManager.java
index 023eccbd27d3..c27063752c58 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/security/access/AuthManager.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/security/access/AuthManager.java
@@ -27,6 +27,7 @@
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.AuthUtil;
 import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.TableName;
 import org.apache.hadoop.hbase.exceptions.DeserializationException;
 import org.apache.hadoop.hbase.security.Superusers;
@@ -452,7 +453,9 @@ private boolean authorizeFamily(Set<TablePermission> permissions, TableName tabl
    */
   public boolean authorizeCell(User user, TableName table, Cell cell, Permission.Action action) {
     try {
-      List<Permission> perms = PermissionStorage.getCellPermissionsForUser(user, cell);
+      assert cell instanceof ExtendedCell;
+      List<Permission> perms =
+        PermissionStorage.getCellPermissionsForUser(user, (ExtendedCell) cell);
       if (LOG.isTraceEnabled()) {
         LOG.trace("Perms for user {} in table {} in cell {}: {}", user.getShortName(), table, cell,
           (perms != null ? perms : ""));
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/security/access/PermissionStorage.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/security/access/PermissionStorage.java
index 7a4444291017..b66c0ed0b099 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/security/access/PermissionStorage.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/security/access/PermissionStorage.java
@@ -38,6 +38,7 @@
 import org.apache.hadoop.hbase.CellBuilderType;
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.CompareOperator;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.NamespaceDescriptor;
 import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.TableName;
@@ -866,7 +867,7 @@ public static byte[] fromNamespaceEntry(byte[] namespace) {
     return Arrays.copyOfRange(namespace, 1, namespace.length);
   }
 
-  public static List<Permission> getCellPermissionsForUser(User user, Cell cell)
+  public static List<Permission> getCellPermissionsForUser(User user, ExtendedCell cell)
     throws IOException {
     // Save an object allocation where we can
     if (cell.getTagsLength() == 0) {
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/TestCustomPriorityRpcControllerFactory.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/TestCustomPriorityRpcControllerFactory.java
index fde491983cea..435037ab17d2 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/TestCustomPriorityRpcControllerFactory.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/TestCustomPriorityRpcControllerFactory.java
@@ -281,12 +281,12 @@ public HBaseRpcController newController() {
     }
 
     @Override
-    public HBaseRpcController newController(CellScanner cellScanner) {
+    public HBaseRpcController newController(ExtendedCellScanner cellScanner) {
       return new PriorityController(EXPECTED_PRIORITY.get(), super.newController(cellScanner));
     }
 
     @Override
-    public HBaseRpcController newController(List<CellScannable> cellIterables) {
+    public HBaseRpcController newController(List<ExtendedCellScannable> cellIterables) {
       return new PriorityController(EXPECTED_PRIORITY.get(), super.newController(cellIterables));
     }
   }
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestFromClientSide.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestFromClientSide.java
index 8e5895c6914e..2e4a13fc8ce4 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestFromClientSide.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestFromClientSide.java
@@ -37,6 +37,7 @@
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.CompareOperator;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
 import org.apache.hadoop.hbase.HConstants;
@@ -232,7 +233,7 @@ public void testKeepDeletedCells() throws Exception {
       s.setTimeRange(0, ts + 3);
       s.readAllVersions();
       ResultScanner scanner = h.getScanner(s);
-      Cell[] kvs = scanner.next().rawCells();
+      ExtendedCell[] kvs = scanner.next().rawExtendedCells();
       assertArrayEquals(T2, CellUtil.cloneValue(kvs[0]));
       assertArrayEquals(T1, CellUtil.cloneValue(kvs[1]));
       scanner.close();
@@ -241,7 +242,7 @@ public void testKeepDeletedCells() throws Exception {
       s.setRaw(true);
       s.readAllVersions();
       scanner = h.getScanner(s);
-      kvs = scanner.next().rawCells();
+      kvs = scanner.next().rawExtendedCells();
       assertTrue(PrivateCellUtil.isDeleteFamily(kvs[0]));
       assertArrayEquals(T3, CellUtil.cloneValue(kvs[1]));
       assertTrue(CellUtil.isDelete(kvs[2]));
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestIncrementsFromClientSide.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestIncrementsFromClientSide.java
index f2b0f75724d8..be70c4c5cd64 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestIncrementsFromClientSide.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestIncrementsFromClientSide.java
@@ -35,6 +35,7 @@
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellBuilderType;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.ExtendedCellBuilderFactory;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
@@ -566,8 +567,8 @@ public void testIncrementWithTtlTags() throws Exception {
         int count = 0;
         Result result;
         while ((result = scanner.next()) != null) {
-          Cell[] cells = result.rawCells();
-          for (Cell cell : cells) {
+          ExtendedCell[] cells = result.rawExtendedCells();
+          for (ExtendedCell cell : cells) {
             List<Tag> tags = PrivateCellUtil.getTags(cell);
             // Make sure there is only 1 tag.
             assertEquals(1, tags.size());
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestMalformedCellFromClient.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestMalformedCellFromClient.java
index 64f4c89a34fa..37422c1f1a0f 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestMalformedCellFromClient.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestMalformedCellFromClient.java
@@ -32,9 +32,11 @@
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.CompareOperator;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
 import org.apache.hadoop.hbase.HConstants;
+import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.TableName;
 import org.apache.hadoop.hbase.ipc.HBaseRpcController;
 import org.apache.hadoop.hbase.regionserver.HRegion;
@@ -199,14 +201,15 @@ public void testAtomicOperations() throws Exception {
             ProtobufUtil.toMutationNoData(ClientProtos.MutationProto.MutationType.PUT, put))))
         .build();
 
-    List<Cell> cells = new ArrayList<>();
+    List<ExtendedCell> cells = new ArrayList<>();
     for (Mutation m : rm.getMutations()) {
       cells.addAll(m.getCellList(FAMILY));
     }
     cells.addAll(put.getCellList(FAMILY));
     assertEquals(3, cells.size());
     HBaseRpcController controller = Mockito.mock(HBaseRpcController.class);
-    Mockito.when(controller.cellScanner()).thenReturn(CellUtil.createCellScanner(cells));
+    Mockito.when(controller.cellScanner())
+      .thenReturn(PrivateCellUtil.createExtendedCellScanner(cells));
     HRegionServer rs = TEST_UTIL.getMiniHBaseCluster().getRegionServer(TEST_UTIL
       .getMiniHBaseCluster().getServerHoldingRegion(TABLE_NAME, r.getRegionInfo().getRegionName()));
 
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/codec/CodecPerformance.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/codec/CodecPerformance.java
index 272bf1c46096..2481cb200d80 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/codec/CodecPerformance.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/codec/CodecPerformance.java
@@ -24,7 +24,8 @@
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCell;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.io.CellOutputStream;
 import org.apache.hadoop.hbase.util.Bytes;
@@ -42,8 +43,8 @@ public class CodecPerformance {
   @Deprecated
   public static final Logger LOG = LoggerFactory.getLogger(CodecPerformance.class);
 
-  static Cell[] getCells(final int howMany) {
-    Cell[] cells = new Cell[howMany];
+  static ExtendedCell[] getCells(final int howMany) {
+    ExtendedCell[] cells = new ExtendedCell[howMany];
     for (int i = 0; i < howMany; i++) {
       byte[] index = Bytes.toBytes(i);
       KeyValue kv = new KeyValue(index, Bytes.toBytes("f"), index, index);
@@ -62,7 +63,7 @@ static int getRoughSize(final Cell[] cells) {
   }
 
   static byte[] runEncoderTest(final int index, final int initialBufferSize,
-    final ByteArrayOutputStream baos, final CellOutputStream encoder, final Cell[] cells)
+    final ByteArrayOutputStream baos, final CellOutputStream encoder, final ExtendedCell[] cells)
     throws IOException {
     long startTime = EnvironmentEdgeManager.currentTime();
     for (int i = 0; i < cells.length; i++) {
@@ -76,9 +77,9 @@ static byte[] runEncoderTest(final int index, final int initialBufferSize,
     return baos.toByteArray();
   }
 
-  static Cell[] runDecoderTest(final int index, final int count, final CellScanner decoder)
-    throws IOException {
-    Cell[] cells = new Cell[count];
+  static ExtendedCell[] runDecoderTest(final int index, final int count,
+    final ExtendedCellScanner decoder) throws IOException {
+    ExtendedCell[] cells = new ExtendedCell[count];
     long startTime = EnvironmentEdgeManager.currentTime();
     for (int i = 0; decoder.advance(); i++) {
       cells[i] = decoder.current();
@@ -94,10 +95,10 @@ static void verifyCells(final Cell[] input, final Cell[] output) {
     assertArrayEquals(input, output);
   }
 
-  static void doCodec(final Codec codec, final Cell[] cells, final int cycles, final int count,
-    final int initialBufferSize) throws IOException {
+  static void doCodec(final Codec codec, final ExtendedCell[] cells, final int cycles,
+    final int count, final int initialBufferSize) throws IOException {
     byte[] bytes = null;
-    Cell[] cellsDecoded = null;
+    ExtendedCell[] cellsDecoded = null;
     for (int i = 0; i < cycles; i++) {
       ByteArrayOutputStream baos = new ByteArrayOutputStream(initialBufferSize);
       Codec.Encoder encoder = codec.getEncoder(baos);
@@ -117,7 +118,7 @@ public static void main(String[] args) throws IOException {
     // How many times to do an operation; repeat gives hotspot chance to warm up.
     final int cycles = 30;
 
-    Cell[] cells = getCells(count);
+    ExtendedCell[] cells = getCells(count);
     int size = getRoughSize(cells);
     int initialBufferSize = 2 * size; // Multiply by 2 to ensure we don't have to grow buffer
 
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/codec/TestCellMessageCodec.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/codec/TestCellMessageCodec.java
index d580c3d7ff18..657f770dd32a 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/codec/TestCellMessageCodec.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/codec/TestCellMessageCodec.java
@@ -26,10 +26,10 @@
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
 import java.io.IOException;
-import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.KeyValue;
+import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.testclassification.MiscTests;
 import org.apache.hadoop.hbase.testclassification.SmallTests;
 import org.apache.hadoop.hbase.util.Bytes;
@@ -116,14 +116,14 @@ public void testThree() throws IOException {
     DataInputStream dis = new DataInputStream(cis);
     Codec.Decoder decoder = cmc.getDecoder(dis);
     assertTrue(decoder.advance());
-    Cell c = decoder.current();
-    assertTrue(CellUtil.equals(c, kv1));
+    ExtendedCell c = decoder.current();
+    assertTrue(PrivateCellUtil.equals(c, kv1));
     assertTrue(decoder.advance());
     c = decoder.current();
-    assertTrue(CellUtil.equals(c, kv2));
+    assertTrue(PrivateCellUtil.equals(c, kv2));
     assertTrue(decoder.advance());
     c = decoder.current();
-    assertTrue(CellUtil.equals(c, kv3));
+    assertTrue(PrivateCellUtil.equals(c, kv3));
     assertFalse(decoder.advance());
     dis.close();
     assertEquals(offset, cis.getCount());
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/coprocessor/TestPostIncrementAndAppendBeforeWAL.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/coprocessor/TestPostIncrementAndAppendBeforeWAL.java
index 406618295ca0..64f47e1d1bac 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/coprocessor/TestPostIncrementAndAppendBeforeWAL.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/coprocessor/TestPostIncrementAndAppendBeforeWAL.java
@@ -30,6 +30,7 @@
 import org.apache.hadoop.hbase.CellBuilderType;
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.ExtendedCellBuilderFactory;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
@@ -247,7 +248,7 @@ public void testAppendTTLWithACLTag() throws Exception {
     }
   }
 
-  private static boolean checkAclTag(byte[] acl, Cell cell) {
+  private static boolean checkAclTag(byte[] acl, ExtendedCell cell) {
     Iterator<Tag> iter = PrivateCellUtil.tagsIterator(cell);
     while (iter.hasNext()) {
       Tag tag = iter.next();
@@ -342,7 +343,10 @@ public List<Pair<Cell, Cell>> postIncrementBeforeWAL(
       List<Pair<Cell, Cell>> cellPairs) throws IOException {
       List<Pair<Cell, Cell>> result = super.postIncrementBeforeWAL(ctx, mutation, cellPairs);
       for (Pair<Cell, Cell> pair : result) {
-        if (mutation.getACL() != null && !checkAclTag(mutation.getACL(), pair.getSecond())) {
+        if (
+          mutation.getACL() != null
+            && !checkAclTag(mutation.getACL(), (ExtendedCell) pair.getSecond())
+        ) {
           throw new DoNotRetryIOException("Unmatched ACL tag.");
         }
       }
@@ -355,7 +359,10 @@ public List<Pair<Cell, Cell>> postAppendBeforeWAL(
       List<Pair<Cell, Cell>> cellPairs) throws IOException {
       List<Pair<Cell, Cell>> result = super.postAppendBeforeWAL(ctx, mutation, cellPairs);
       for (Pair<Cell, Cell> pair : result) {
-        if (mutation.getACL() != null && !checkAclTag(mutation.getACL(), pair.getSecond())) {
+        if (
+          mutation.getACL() != null
+            && !checkAclTag(mutation.getACL(), (ExtendedCell) pair.getSecond())
+        ) {
           throw new DoNotRetryIOException("Unmatched ACL tag.");
         }
       }
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/filter/TestFilterList.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/filter/TestFilterList.java
index f64381a8a22e..26144d4adea4 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/filter/TestFilterList.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/filter/TestFilterList.java
@@ -31,6 +31,7 @@
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellComparator;
 import org.apache.hadoop.hbase.CompareOperator;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.KeyValueUtil;
@@ -554,12 +555,14 @@ Lists.<Filter> newArrayList(
 
     // Value for fam:qual1 should be stripped:
     assertEquals(Filter.ReturnCode.INCLUDE, flist.filterCell(kvQual1));
-    final KeyValue transformedQual1 = KeyValueUtil.ensureKeyValue(flist.transformCell(kvQual1));
+    final KeyValue transformedQual1 =
+      KeyValueUtil.ensureKeyValue((ExtendedCell) flist.transformCell(kvQual1));
     assertEquals(0, transformedQual1.getValueLength());
 
     // Value for fam:qual2 should not be stripped:
     assertEquals(Filter.ReturnCode.INCLUDE, flist.filterCell(kvQual2));
-    final KeyValue transformedQual2 = KeyValueUtil.ensureKeyValue(flist.transformCell(kvQual2));
+    final KeyValue transformedQual2 =
+      KeyValueUtil.ensureKeyValue((ExtendedCell) flist.transformCell(kvQual2));
     assertEquals("value", Bytes.toString(transformedQual2.getValueArray(),
       transformedQual2.getValueOffset(), transformedQual2.getValueLength()));
 
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/io/compress/HFileTestBase.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/io/compress/HFileTestBase.java
index 024fb04c6873..afbaceebeea1 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/io/compress/HFileTestBase.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/io/compress/HFileTestBase.java
@@ -27,7 +27,7 @@
 import org.apache.hadoop.fs.FSDataOutputStream;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.KeyValue;
@@ -88,7 +88,7 @@ public void doTest(Configuration conf, Path path, Compression.Algorithm compress
       scanner = reader.getScanner(conf, false, false);
       assertTrue("Initial seekTo failed", scanner.seekTo());
       do {
-        Cell kv = scanner.getCell();
+        ExtendedCell kv = scanner.getCell();
         assertTrue("Read back an unexpected or invalid KV",
           testKvs.contains(KeyValueUtil.ensureKeyValue(kv)));
         i++;
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/io/encoding/TestBufferedDataBlockEncoder.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/io/encoding/TestBufferedDataBlockEncoder.java
index 68ce5e359f56..24d69d88c101 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/io/encoding/TestBufferedDataBlockEncoder.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/io/encoding/TestBufferedDataBlockEncoder.java
@@ -24,11 +24,11 @@
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.nio.ByteBuffer;
-import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.KeyValue.Type;
+import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.codec.Codec.Decoder;
 import org.apache.hadoop.hbase.codec.Codec.Encoder;
 import org.apache.hadoop.hbase.codec.KeyValueCodecWithTags;
@@ -127,11 +127,11 @@ public void testKVCodecWithTagsForDecodedCellsWithNoTags() throws Exception {
     ByteArrayInputStream is = new ByteArrayInputStream(os.toByteArray());
     Decoder decoder = codec.getDecoder(is);
     assertTrue(decoder.advance());
-    assertTrue(CellUtil.equals(c1, decoder.current()));
+    assertTrue(PrivateCellUtil.equals(c1, decoder.current()));
     assertTrue(decoder.advance());
-    assertTrue(CellUtil.equals(c2, decoder.current()));
+    assertTrue(PrivateCellUtil.equals(c2, decoder.current()));
     assertTrue(decoder.advance());
-    assertTrue(CellUtil.equals(c3, decoder.current()));
+    assertTrue(PrivateCellUtil.equals(c3, decoder.current()));
     assertFalse(decoder.advance());
   }
 }
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/io/encoding/TestDataBlockEncoders.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/io/encoding/TestDataBlockEncoders.java
index 6ae5a74ebe8d..a37c5a5a5f90 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/io/encoding/TestDataBlockEncoders.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/io/encoding/TestDataBlockEncoders.java
@@ -327,7 +327,7 @@ public void testNextOnSample() throws IOException {
       int i = 0;
       do {
         KeyValue expectedKeyValue = sampleKv.get(i);
-        Cell cell = seeker.getCell();
+        ExtendedCell cell = seeker.getCell();
         if (
           PrivateCellUtil.compareKeyIgnoresMvcc(CellComparatorImpl.COMPARATOR, expectedKeyValue,
             cell) != 0
@@ -360,7 +360,7 @@ public void testFirstKeyInBlockOnSample() throws IOException {
       DataBlockEncoder encoder = encoding.getEncoder();
       ByteBuffer encodedBuffer = encodeKeyValues(encoding, sampleKv,
         getEncodingContext(conf, Compression.Algorithm.NONE, encoding), this.useOffheapData);
-      Cell key = encoder.getFirstKeyCellInBlock(new SingleByteBuff(encodedBuffer));
+      ExtendedCell key = encoder.getFirstKeyCellInBlock(new SingleByteBuff(encodedBuffer));
       KeyValue firstKv = sampleKv.get(0);
       if (0 != PrivateCellUtil.compareKeyIgnoresMvcc(CellComparatorImpl.COMPARATOR, key, firstKv)) {
         int commonPrefix = PrivateCellUtil.findCommonPrefixInFlatKey(key, firstKv, false, true);
@@ -394,20 +394,20 @@ public void testRowIndexWithTagsButNoTagsInCell() throws IOException {
 
   private void checkSeekingConsistency(List<DataBlockEncoder.EncodedSeeker> encodedSeekers,
     boolean seekBefore, ExtendedCell keyValue) {
-    Cell expectedKeyValue = null;
+    ExtendedCell expectedKeyValue = null;
     ByteBuffer expectedKey = null;
     ByteBuffer expectedValue = null;
     for (DataBlockEncoder.EncodedSeeker seeker : encodedSeekers) {
       seeker.seekToKeyInBlock(keyValue, seekBefore);
       seeker.rewind();
 
-      Cell actualKeyValue = seeker.getCell();
+      ExtendedCell actualKeyValue = seeker.getCell();
       ByteBuffer actualKey = null;
       actualKey = ByteBuffer.wrap(((KeyValue) seeker.getKey()).getKey());
       ByteBuffer actualValue = seeker.getValueShallowCopy();
 
       if (expectedKeyValue != null) {
-        assertTrue(CellUtil.equals(expectedKeyValue, actualKeyValue));
+        assertTrue(PrivateCellUtil.equals(expectedKeyValue, actualKeyValue));
       } else {
         expectedKeyValue = actualKeyValue;
       }
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/io/hfile/TestHFileEncryption.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/io/hfile/TestHFileEncryption.java
index f3711428ce53..663c0d540499 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/io/hfile/TestHFileEncryption.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/io/hfile/TestHFileEncryption.java
@@ -34,7 +34,7 @@
 import org.apache.hadoop.fs.FSDataOutputStream;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseCommonTestingUtil;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
@@ -244,7 +244,7 @@ public void testHFileEncryption() throws Exception {
           scanner = reader.getScanner(conf, false, false);
           assertTrue("Initial seekTo failed", scanner.seekTo());
           do {
-            Cell kv = scanner.getCell();
+            ExtendedCell kv = scanner.getCell();
             assertTrue("Read back an unexpected or invalid KV",
               testKvs.contains(KeyValueUtil.ensureKeyValue(kv)));
             i++;
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/io/hfile/TestScannerFromBucketCache.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/io/hfile/TestScannerFromBucketCache.java
index 837ee17110ec..ec1ebfd9d633 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/io/hfile/TestScannerFromBucketCache.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/io/hfile/TestScannerFromBucketCache.java
@@ -26,7 +26,7 @@
 import java.util.List;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.ByteBufferKeyValue;
-import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
 import org.apache.hadoop.hbase.HConstants;
@@ -116,9 +116,9 @@ public void testBasicScanWithLRUCache() throws IOException {
     String method = this.getName();
     this.region = initHRegion(tableName, method, conf, test_util, fam1);
     try {
-      List<Cell> expected = insertData(row1, qf1, qf2, fam1, ts1, ts2, ts3, false);
+      List<ExtendedCell> expected = insertData(row1, qf1, qf2, fam1, ts1, ts2, ts3, false);
 
-      List<Cell> actual = performScan(row1, fam1);
+      List<ExtendedCell> actual = performScan(row1, fam1);
       // Verify result
       for (int i = 0; i < expected.size(); i++) {
         assertFalse(actual.get(i) instanceof ByteBufferKeyValue);
@@ -154,9 +154,9 @@ public void testBasicScanWithOffheapBucketCache() throws IOException {
     String method = this.getName();
     this.region = initHRegion(tableName, method, conf, test_util, fam1);
     try {
-      List<Cell> expected = insertData(row1, qf1, qf2, fam1, ts1, ts2, ts3, false);
+      List<ExtendedCell> expected = insertData(row1, qf1, qf2, fam1, ts1, ts2, ts3, false);
 
-      List<Cell> actual = performScan(row1, fam1);
+      List<ExtendedCell> actual = performScan(row1, fam1);
       // Verify result
       for (int i = 0; i < expected.size(); i++) {
         assertFalse(actual.get(i) instanceof ByteBufferKeyValue);
@@ -195,9 +195,9 @@ public void testBasicScanWithOffheapBucketCacheWithMBB() throws IOException {
     String method = this.getName();
     this.region = initHRegion(tableName, method, conf, test_util, fam1);
     try {
-      List<Cell> expected = insertData(row1, qf1, qf2, fam1, ts1, ts2, ts3, true);
+      List<ExtendedCell> expected = insertData(row1, qf1, qf2, fam1, ts1, ts2, ts3, true);
 
-      List<Cell> actual = performScan(row1, fam1);
+      List<ExtendedCell> actual = performScan(row1, fam1);
       // Verify result
       for (int i = 0; i < expected.size(); i++) {
         assertFalse(actual.get(i) instanceof ByteBufferKeyValue);
@@ -211,7 +211,7 @@ public void testBasicScanWithOffheapBucketCacheWithMBB() throws IOException {
       actual = new ArrayList<>();
       InternalScanner scanner = region.getScanner(scan);
 
-      boolean hasNext = scanner.next(actual);
+      boolean hasNext = scanner.next((List) actual);
       assertEquals(false, hasNext);
       // Verify result
       for (int i = 0; i < expected.size(); i++) {
@@ -229,7 +229,7 @@ public void testBasicScanWithOffheapBucketCacheWithMBB() throws IOException {
     }
   }
 
-  private List<Cell> insertData(byte[] row1, byte[] qf1, byte[] qf2, byte[] fam1, long ts1,
+  private List<ExtendedCell> insertData(byte[] row1, byte[] qf1, byte[] qf2, byte[] fam1, long ts1,
     long ts2, long ts3, boolean withVal) throws IOException {
     // Putting data in Region
     Put put = null;
@@ -276,7 +276,7 @@ private List<Cell> insertData(byte[] row1, byte[] qf1, byte[] qf2, byte[] fam1,
     }
 
     // Expected
-    List<Cell> expected = new ArrayList<>();
+    List<ExtendedCell> expected = new ArrayList<>();
     expected.add(kv13);
     expected.add(kv12);
     expected.add(kv23);
@@ -284,12 +284,12 @@ private List<Cell> insertData(byte[] row1, byte[] qf1, byte[] qf2, byte[] fam1,
     return expected;
   }
 
-  private List<Cell> performScan(byte[] row1, byte[] fam1) throws IOException {
+  private List<ExtendedCell> performScan(byte[] row1, byte[] fam1) throws IOException {
     Scan scan = new Scan().withStartRow(row1).addFamily(fam1).readVersions(MAX_VERSIONS);
-    List<Cell> actual = new ArrayList<>();
+    List<ExtendedCell> actual = new ArrayList<>();
     InternalScanner scanner = region.getScanner(scan);
 
-    boolean hasNext = scanner.next(actual);
+    boolean hasNext = scanner.next((List) actual);
     assertEquals(false, hasNext);
     return actual;
   }
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/io/hfile/TestSeekBeforeWithInlineBlocks.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/io/hfile/TestSeekBeforeWithInlineBlocks.java
index 04c38127d51f..f07238e134d2 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/io/hfile/TestSeekBeforeWithInlineBlocks.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/io/hfile/TestSeekBeforeWithInlineBlocks.java
@@ -25,13 +25,13 @@
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.KeyValue;
+import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.fs.HFileSystem;
 import org.apache.hadoop.hbase.regionserver.BloomType;
 import org.apache.hadoop.hbase.regionserver.StoreFileWriter;
@@ -178,8 +178,8 @@ private void checkNoSeekBefore(ExtendedCell[] cells, HFileScanner scanner, int i
   }
 
   /** Check a key/value pair after it was read by the reader */
-  private void checkCell(Cell expected, Cell actual) {
+  private void checkCell(ExtendedCell expected, ExtendedCell actual) {
     assertTrue(String.format("Expected key %s, but was %s", CellUtil.getCellKeyAsString(expected),
-      CellUtil.getCellKeyAsString(actual)), CellUtil.equals(expected, actual));
+      CellUtil.getCellKeyAsString(actual)), PrivateCellUtil.equals(expected, actual));
   }
 }
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/io/hfile/TestSeekTo.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/io/hfile/TestSeekTo.java
index bf26b019e2a1..4c55c85f9035 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/io/hfile/TestSeekTo.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/io/hfile/TestSeekTo.java
@@ -33,6 +33,7 @@
 import org.apache.hadoop.hbase.ArrayBackedTag;
 import org.apache.hadoop.hbase.ByteBufferKeyValue;
 import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
 import org.apache.hadoop.hbase.HConstants;
@@ -171,7 +172,7 @@ protected void testSeekBeforeInternals(TagUsage tagUsage) throws IOException {
     assertEquals("g", toRowStr(scanner.getCell()));
     assertTrue(scanner.seekBefore(toKV("j", tagUsage)));
     assertEquals("i", toRowStr(scanner.getCell()));
-    Cell cell = scanner.getCell();
+    ExtendedCell cell = scanner.getCell();
     if (tagUsage != TagUsage.NO_TAG && cell.getTagsLength() > 0) {
       Iterator<Tag> tagsIterator = PrivateCellUtil.tagsIterator(cell);
       while (tagsIterator.hasNext()) {
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/ipc/AbstractTestIPC.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/ipc/AbstractTestIPC.java
index 0f0c22baf9fc..248e8f9d8cef 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/ipc/AbstractTestIPC.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/ipc/AbstractTestIPC.java
@@ -62,14 +62,14 @@
 import java.util.Collections;
 import java.util.List;
 import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellScanner;
-import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.HBaseServerBase;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.MatcherPredicate;
+import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.Server;
 import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.Waiter;
@@ -176,7 +176,7 @@ public void testNoCodec() throws IOException, ServiceException {
   public void testCompressCellBlock() throws IOException, ServiceException {
     Configuration clientConf = new Configuration(CONF);
     clientConf.set("hbase.client.rpc.compressor", GzipCodec.class.getCanonicalName());
-    List<Cell> cells = new ArrayList<>();
+    List<ExtendedCell> cells = new ArrayList<>();
     int count = 3;
     for (int i = 0; i < count; i++) {
       cells.add(CELL);
@@ -188,7 +188,8 @@ public void testCompressCellBlock() throws IOException, ServiceException {
     try (AbstractRpcClient<?> client = createRpcClient(clientConf)) {
       rpcServer.start();
       BlockingInterface stub = newBlockingStub(client, rpcServer.getListenerAddress());
-      HBaseRpcController pcrc = new HBaseRpcControllerImpl(CellUtil.createCellScanner(cells));
+      HBaseRpcController pcrc =
+        new HBaseRpcControllerImpl(PrivateCellUtil.createExtendedCellScanner(cells));
       String message = "hello";
       assertEquals(message,
         stub.echo(pcrc, EchoRequestProto.newBuilder().setMessage(message).build()).getMessage());
@@ -270,9 +271,8 @@ public void testRpcMaxRequestSize() throws IOException, ServiceException {
       }
       // set total RPC size bigger than 100 bytes
       EchoRequestProto param = EchoRequestProto.newBuilder().setMessage(message.toString()).build();
-      stub.echo(
-        new HBaseRpcControllerImpl(CellUtil.createCellScanner(ImmutableList.<Cell> of(CELL))),
-        param);
+      stub.echo(new HBaseRpcControllerImpl(
+        PrivateCellUtil.createExtendedCellScanner(ImmutableList.<ExtendedCell> of(CELL))), param);
       fail("RPC should have failed because it exceeds max request size");
     } catch (ServiceException e) {
       LOG.info("Caught expected exception: " + e);
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/ipc/TestNettyChannelWritability.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/ipc/TestNettyChannelWritability.java
index 001f6dbd22c7..64fc47ca1940 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/ipc/TestNettyChannelWritability.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/ipc/TestNettyChannelWritability.java
@@ -32,13 +32,13 @@
 import java.util.concurrent.CompletionException;
 import java.util.concurrent.atomic.AtomicInteger;
 import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellScanner;
-import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.CompatibilityFactory;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.KeyValue;
+import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.test.MetricsAssertHelper;
 import org.apache.hadoop.hbase.testclassification.MediumTests;
 import org.apache.hadoop.hbase.testclassification.RPCTests;
@@ -112,7 +112,7 @@ public void testNettyWritableFatalThreshold() throws Exception {
 
   private void sendAndReceive(Configuration conf, NettyRpcServer rpcServer, int requestCount)
     throws Exception {
-    List<Cell> cells = new ArrayList<>();
+    List<ExtendedCell> cells = new ArrayList<>();
     int count = 3;
     for (int i = 0; i < count; i++) {
       cells.add(CELL);
@@ -136,9 +136,10 @@ private void sendAndReceive(Configuration conf, NettyRpcServer rpcServer, int re
     }
   }
 
-  private void sendMessage(List<Cell> cells,
+  private void sendMessage(List<ExtendedCell> cells,
     TestRpcServiceProtos.TestProtobufRpcProto.BlockingInterface stub) throws Exception {
-    HBaseRpcController pcrc = new HBaseRpcControllerImpl(CellUtil.createCellScanner(cells));
+    HBaseRpcController pcrc =
+      new HBaseRpcControllerImpl(PrivateCellUtil.createExtendedCellScanner(cells));
     String message = "hello";
     assertEquals(message,
       stub.echo(pcrc, TestProtos.EchoRequestProto.newBuilder().setMessage(message).build())
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/ipc/TestProtobufRpcServiceImpl.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/ipc/TestProtobufRpcServiceImpl.java
index b2ac0a3deb9b..edb9a64a7a8e 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/ipc/TestProtobufRpcServiceImpl.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/ipc/TestProtobufRpcServiceImpl.java
@@ -21,10 +21,10 @@
 import java.net.InetSocketAddress;
 import java.util.ArrayList;
 import java.util.List;
-import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.CellScanner;
-import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
+import org.apache.hadoop.hbase.ExtendedCell;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
+import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.security.User;
 import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
@@ -82,8 +82,8 @@ public EchoResponseProto echo(RpcController controller, EchoRequestProto request
       HBaseRpcController pcrc = (HBaseRpcController) controller;
       // If cells, scan them to check we are able to iterate what we were given and since this is an
       // echo, just put them back on the controller creating a new block. Tests our block building.
-      CellScanner cellScanner = pcrc.cellScanner();
-      List<Cell> list = null;
+      ExtendedCellScanner cellScanner = pcrc.cellScanner();
+      List<ExtendedCell> list = null;
       if (cellScanner != null) {
         list = new ArrayList<>();
         try {
@@ -94,7 +94,7 @@ public EchoResponseProto echo(RpcController controller, EchoRequestProto request
           throw new ServiceException(e);
         }
       }
-      cellScanner = CellUtil.createCellScanner(list);
+      cellScanner = PrivateCellUtil.createExtendedCellScanner(list);
       pcrc.setCellScanner(cellScanner);
     }
     return EchoResponseProto.newBuilder().setMessage(request.getMessage()).build();
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/master/MockRegionServer.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/master/MockRegionServer.java
index a7164a6fab64..a25bae6ec7bd 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/master/MockRegionServer.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/master/MockRegionServer.java
@@ -33,10 +33,10 @@
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.hbase.Abortable;
-import org.apache.hadoop.hbase.CellScannable;
-import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.ChoreService;
 import org.apache.hadoop.hbase.CoordinatedStateManager;
+import org.apache.hadoop.hbase.ExtendedCellScannable;
+import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.TableDescriptors;
 import org.apache.hadoop.hbase.TableName;
@@ -388,9 +388,10 @@ public ScanResponse scan(RpcController controller, ScanRequest request) throws S
         Result result = next(scannerId);
         if (result != null) {
           builder.addCellsPerResult(result.size());
-          List<CellScannable> results = new ArrayList<>(1);
+          List<ExtendedCellScannable> results = new ArrayList<>(1);
           results.add(result);
-          ((HBaseRpcController) controller).setCellScanner(CellUtil.createCellScanner(results));
+          ((HBaseRpcController) controller)
+            .setCellScanner(PrivateCellUtil.createExtendedCellScanner(results));
           builder.setMoreResults(true);
         } else {
           builder.setMoreResults(false);
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/mob/TestMobStoreCompaction.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/mob/TestMobStoreCompaction.java
index c2f2b3fd4260..835d8b83d69e 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/mob/TestMobStoreCompaction.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/mob/TestMobStoreCompaction.java
@@ -39,6 +39,7 @@
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
 import org.apache.hadoop.hbase.HConstants;
@@ -373,11 +374,11 @@ private int countMobRows() throws IOException {
     InternalScanner scanner = region.getScanner(scan);
 
     int scannedCount = 0;
-    List<Cell> results = new ArrayList<>();
+    List<ExtendedCell> results = new ArrayList<>();
     boolean hasMore = true;
     while (hasMore) {
-      hasMore = scanner.next(results);
-      for (Cell c : results) {
+      hasMore = scanner.next((List) results);
+      for (ExtendedCell c : results) {
         if (MobUtils.isMobReferenceCell(c)) {
           scannedCount++;
         }
@@ -401,15 +402,15 @@ private int countReferencedMobFiles() throws IOException {
     scan.setAttribute(MobConstants.MOB_SCAN_RAW, Bytes.toBytes(Boolean.TRUE));
     InternalScanner scanner = region.getScanner(scan);
 
-    List<Cell> kvs = new ArrayList<>();
+    List<ExtendedCell> kvs = new ArrayList<>();
     boolean hasMore = true;
     String fileName;
     Set<String> files = new HashSet<>();
     do {
       kvs.clear();
-      hasMore = scanner.next(kvs);
+      hasMore = scanner.next((List) kvs);
       for (Cell kv : kvs) {
-        if (!MobUtils.isMobReferenceCell(kv)) {
+        if (!MobUtils.isMobReferenceCell((ExtendedCell) kv)) {
           continue;
         }
         if (!MobUtils.hasValidMobRefCellValue(kv)) {
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/namequeues/TestNamedQueueRecorder.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/namequeues/TestNamedQueueRecorder.java
index 124214e46af3..05243bd93a6c 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/namequeues/TestNamedQueueRecorder.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/namequeues/TestNamedQueueRecorder.java
@@ -31,7 +31,7 @@
 import java.util.concurrent.TimeUnit;
 import java.util.stream.Collectors;
 import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
 import org.apache.hadoop.hbase.HConstants;
@@ -717,7 +717,7 @@ public Message getParam() {
       }
 
       @Override
-      public CellScanner getCellScanner() {
+      public ExtendedCellScanner getCellScanner() {
         return null;
       }
 
@@ -783,7 +783,7 @@ public int getRemotePort() {
       }
 
       @Override
-      public void setResponse(Message param, CellScanner cells, Throwable errorThrowable,
+      public void setResponse(Message param, ExtendedCellScanner cells, Throwable errorThrowable,
         String error) {
       }
 
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/namequeues/TestRpcLogDetails.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/namequeues/TestRpcLogDetails.java
index 1de0a0d31a33..4ec3e90aad86 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/namequeues/TestRpcLogDetails.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/namequeues/TestRpcLogDetails.java
@@ -29,7 +29,7 @@
 import java.util.Collections;
 import java.util.Map;
 import java.util.Optional;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.ipc.RpcCall;
 import org.apache.hadoop.hbase.ipc.RpcCallback;
@@ -118,7 +118,7 @@ public Message getParam() {
       }
 
       @Override
-      public CellScanner getCellScanner() {
+      public ExtendedCellScanner getCellScanner() {
         return null;
       }
 
@@ -182,7 +182,7 @@ public int getRemotePort() {
       }
 
       @Override
-      public void setResponse(Message param, CellScanner cells, Throwable errorThrowable,
+      public void setResponse(Message param, ExtendedCellScanner cells, Throwable errorThrowable,
         String error) {
       }
 
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/procedure2/store/region/TestRegionProcedureStore.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/procedure2/store/region/TestRegionProcedureStore.java
index fdd5c7d5cf90..b440431f1fb0 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/procedure2/store/region/TestRegionProcedureStore.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/procedure2/store/region/TestRegionProcedureStore.java
@@ -28,7 +28,7 @@
 import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.client.Get;
 import org.apache.hadoop.hbase.ipc.RpcCall;
@@ -184,7 +184,7 @@ public Message getParam() {
       }
 
       @Override
-      public CellScanner getCellScanner() {
+      public ExtendedCellScanner getCellScanner() {
         return null;
       }
 
@@ -244,7 +244,7 @@ public int getRemotePort() {
       }
 
       @Override
-      public void setResponse(Message param, CellScanner cells, Throwable errorThrowable,
+      public void setResponse(Message param, ExtendedCellScanner cells, Throwable errorThrowable,
         String error) {
       }
 
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/protobuf/TestReplicationProtobuf.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/protobuf/TestReplicationProtobuf.java
index 5dd0ce8dafb7..bfbeed768554 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/protobuf/TestReplicationProtobuf.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/protobuf/TestReplicationProtobuf.java
@@ -23,8 +23,8 @@
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
-import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.testclassification.MiscTests;
@@ -46,19 +46,19 @@ public class TestReplicationProtobuf {
    */
   @Test
   public void testGetCellScanner() throws IOException {
-    List<Cell> a = new ArrayList<>();
+    List<ExtendedCell> a = new ArrayList<>();
     KeyValue akv = new KeyValue(Bytes.toBytes("a"), -1L);
     a.add(akv);
     // Add a few just to make it less regular.
     a.add(new KeyValue(Bytes.toBytes("aa"), -1L));
     a.add(new KeyValue(Bytes.toBytes("aaa"), -1L));
-    List<Cell> b = new ArrayList<>();
+    List<ExtendedCell> b = new ArrayList<>();
     KeyValue bkv = new KeyValue(Bytes.toBytes("b"), -1L);
     a.add(bkv);
-    List<Cell> c = new ArrayList<>();
+    List<ExtendedCell> c = new ArrayList<>();
     KeyValue ckv = new KeyValue(Bytes.toBytes("c"), -1L);
     c.add(ckv);
-    List<List<? extends Cell>> all = new ArrayList<>();
+    List<List<? extends ExtendedCell>> all = new ArrayList<>();
     all.add(a);
     all.add(b);
     all.add(c);
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/DataBlockEncodingTool.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/DataBlockEncodingTool.java
index ec9de92e9f25..edabfc51f2bb 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/DataBlockEncodingTool.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/DataBlockEncodingTool.java
@@ -30,7 +30,7 @@
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.KeyValueUtil;
@@ -251,7 +251,7 @@ public boolean verifyCodecs(final KeyValueScanner scanner, final int kvLimit) th
     KeyValue currentKv;
 
     scanner.seek(KeyValue.LOWESTKEY);
-    List<Iterator<Cell>> codecIterators = new ArrayList<>();
+    List<Iterator<ExtendedCell>> codecIterators = new ArrayList<>();
     for (EncodedDataBlock codec : codecs) {
       codecIterators.add(codec.getIterator(HFileBlock.headerSize(useHBaseChecksum)));
     }
@@ -260,8 +260,8 @@ public boolean verifyCodecs(final KeyValueScanner scanner, final int kvLimit) th
     while ((currentKv = KeyValueUtil.ensureKeyValue(scanner.next())) != null && j < kvLimit) {
       // Iterates through key/value pairs
       ++j;
-      for (Iterator<Cell> it : codecIterators) {
-        Cell c = it.next();
+      for (Iterator<ExtendedCell> it : codecIterators) {
+        ExtendedCell c = it.next();
         KeyValue codecKv = KeyValueUtil.ensureKeyValue(c);
         if (
           codecKv == null
@@ -337,7 +337,7 @@ private int benchmarkEncoder(int previousTotalSize, EncodedDataBlock codec) {
     for (int itTime = 0; itTime < benchmarkNTimes; ++itTime) {
       totalSize = 0;
 
-      Iterator<Cell> it;
+      Iterator<ExtendedCell> it;
 
       it = codec.getIterator(HFileBlock.headerSize(useHBaseChecksum));
 
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/EncodedSeekPerformanceTest.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/EncodedSeekPerformanceTest.java
index 601370357744..f33faf8c8e02 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/EncodedSeekPerformanceTest.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/EncodedSeekPerformanceTest.java
@@ -23,7 +23,6 @@
 import java.util.Random;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
 import org.apache.hadoop.hbase.HConstants;
@@ -97,7 +96,7 @@ private void runTest(Path path, DataBlockEncoding blockEncoding, List<ExtendedCe
     StoreFileScanner scanner = reader.getStoreFileScanner(true, false, false, 0, 0, false);
 
     long startReadingTime = System.nanoTime();
-    Cell current;
+    ExtendedCell current;
     scanner.seek(KeyValue.LOWESTKEY);
     while (null != (current = scanner.next())) { // just iterate it!
       if (KeyValueUtil.ensureKeyValue(current).getLength() < 0) {
@@ -111,7 +110,7 @@ private void runTest(Path path, DataBlockEncoding blockEncoding, List<ExtendedCe
     long startSeeksTime = System.nanoTime();
     for (ExtendedCell keyValue : seeks) {
       scanner.seek(keyValue);
-      Cell toVerify = scanner.next();
+      ExtendedCell toVerify = scanner.next();
       if (!keyValue.equals(toVerify)) {
         System.out
           .println(String.format("KeyValue doesn't match:\n" + "Orig key: %s\n" + "Ret key:  %s",
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestBlocksScanned.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestBlocksScanned.java
index 066eaf53cc16..0d0b2d087832 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestBlocksScanned.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestBlocksScanned.java
@@ -24,7 +24,7 @@
 import java.util.List;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
 import org.apache.hadoop.hbase.KeyValueUtil;
@@ -114,8 +114,8 @@ private void _testBlocksScanned(TableDescriptor td) throws Exception {
     scan.readVersions(1);
 
     InternalScanner s = r.getScanner(scan);
-    List<Cell> results = new ArrayList<>();
-    while (s.next(results))
+    List<ExtendedCell> results = new ArrayList<>();
+    while (s.next((List) results))
       ;
     s.close();
 
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestCellFlatSet.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestCellFlatSet.java
index e2f9ac2f34ac..52826e2e8e23 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestCellFlatSet.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestCellFlatSet.java
@@ -31,11 +31,11 @@
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellComparator;
-import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.KeyValueUtil;
+import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.io.util.MemorySizeUtil;
 import org.apache.hadoop.hbase.regionserver.ChunkCreator.ChunkType;
 import org.apache.hadoop.hbase.testclassification.RegionServerTests;
@@ -187,10 +187,10 @@ private void testSubSet(CellSet<ExtendedCell> cs) throws Exception {
       Iterator<ExtendedCell> excludeIter = excludeTail.iterator();
       Iterator<ExtendedCell> includeIter = includeTail.iterator();
       for (int j = 1 + i; j != ascCells.length; ++j) {
-        assertEquals(true, CellUtil.equals(excludeIter.next(), ascCells[j]));
+        assertEquals(true, PrivateCellUtil.equals(excludeIter.next(), ascCells[j]));
       }
       for (int j = i; j != ascCells.length; ++j) {
-        assertEquals(true, CellUtil.equals(includeIter.next(), ascCells[j]));
+        assertEquals(true, PrivateCellUtil.equals(includeIter.next(), ascCells[j]));
       }
     }
     assertEquals(NUM_OF_CELLS, cs.tailSet(lowerOuterCell, false).size());
@@ -203,10 +203,10 @@ private void testSubSet(CellSet<ExtendedCell> cs) throws Exception {
       Iterator<ExtendedCell> excludeIter = excludeHead.iterator();
       Iterator<ExtendedCell> includeIter = includeHead.iterator();
       for (int j = 0; j != i; ++j) {
-        assertEquals(true, CellUtil.equals(excludeIter.next(), ascCells[j]));
+        assertEquals(true, PrivateCellUtil.equals(excludeIter.next(), ascCells[j]));
       }
       for (int j = 0; j != i + 1; ++j) {
-        assertEquals(true, CellUtil.equals(includeIter.next(), ascCells[j]));
+        assertEquals(true, PrivateCellUtil.equals(includeIter.next(), ascCells[j]));
       }
     }
     assertEquals(0, cs.headSet(lowerOuterCell, false).size());
@@ -217,7 +217,7 @@ private void testSubSet(CellSet<ExtendedCell> cs) throws Exception {
     assertEquals(NUM_OF_CELLS, sub.size());
     Iterator<ExtendedCell> iter = sub.values().iterator();
     for (int i = 0; i != ascCells.length; ++i) {
-      assertEquals(true, CellUtil.equals(iter.next(), ascCells[i]));
+      assertEquals(true, PrivateCellUtil.equals(iter.next(), ascCells[i]));
     }
   }
 
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHMobStore.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHMobStore.java
index 53e183f82590..c9e6cd83ec6f 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHMobStore.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHMobStore.java
@@ -311,15 +311,15 @@ public void testGetReferencesFromFiles() throws IOException {
     InternalScanner scanner = (InternalScanner) store.getScanner(scan,
       scan.getFamilyMap().get(store.getColumnFamilyDescriptor().getName()), 0);
 
-    List<Cell> results = new ArrayList<>();
-    scanner.next(results);
+    List<ExtendedCell> results = new ArrayList<>();
+    scanner.next((List) results);
     Collections.sort(results, CellComparatorImpl.COMPARATOR);
     scanner.close();
 
     // Compare
     Assert.assertEquals(expected.size(), results.size());
     for (int i = 0; i < results.size(); i++) {
-      Cell cell = results.get(i);
+      ExtendedCell cell = results.get(i);
       Assert.assertTrue(MobUtils.isMobReferenceCell(cell));
     }
   }
@@ -399,15 +399,15 @@ public void testMobCellSizeThreshold() throws IOException {
     InternalScanner scanner = (InternalScanner) store.getScanner(scan,
       scan.getFamilyMap().get(store.getColumnFamilyDescriptor().getName()), 0);
 
-    List<Cell> results = new ArrayList<>();
-    scanner.next(results);
+    List<ExtendedCell> results = new ArrayList<>();
+    scanner.next((List) results);
     Collections.sort(results, CellComparatorImpl.COMPARATOR);
     scanner.close();
 
     // Compare
     Assert.assertEquals(expected.size(), results.size());
     for (int i = 0; i < results.size(); i++) {
-      Cell cell = results.get(i);
+      ExtendedCell cell = results.get(i);
       // this is not mob reference cell.
       Assert.assertFalse(MobUtils.isMobReferenceCell(cell));
       Assert.assertEquals(expected.get(i), results.get(i));
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHRegion.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHRegion.java
index a271920c0150..d9856b40a831 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHRegion.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHRegion.java
@@ -82,6 +82,7 @@
 import org.apache.hadoop.hbase.CompatibilitySingletonFactory;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
 import org.apache.hadoop.hbase.DroppedSnapshotException;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.ExtendedCellBuilderFactory;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseConfiguration;
@@ -3780,26 +3781,26 @@ public void testRegionScanner_Next() throws IOException {
     scan.addFamily(fam2);
     scan.addFamily(fam4);
     try (InternalScanner is = region.getScanner(scan)) {
-      List<Cell> res = null;
+      List<ExtendedCell> res = null;
 
       // Result 1
-      List<Cell> expected1 = new ArrayList<>();
+      List<ExtendedCell> expected1 = new ArrayList<>();
       expected1.add(new KeyValue(row1, fam2, null, ts, KeyValue.Type.Put, null));
       expected1.add(new KeyValue(row1, fam4, null, ts, KeyValue.Type.Put, null));
 
       res = new ArrayList<>();
-      is.next(res);
+      is.next((List) res);
       for (int i = 0; i < res.size(); i++) {
         assertTrue(PrivateCellUtil.equalsIgnoreMvccVersion(expected1.get(i), res.get(i)));
       }
 
       // Result 2
-      List<Cell> expected2 = new ArrayList<>();
+      List<ExtendedCell> expected2 = new ArrayList<>();
       expected2.add(new KeyValue(row2, fam2, null, ts, KeyValue.Type.Put, null));
       expected2.add(new KeyValue(row2, fam4, null, ts, KeyValue.Type.Put, null));
 
       res = new ArrayList<>();
-      is.next(res);
+      is.next((List) res);
       for (int i = 0; i < res.size(); i++) {
         assertTrue(PrivateCellUtil.equalsIgnoreMvccVersion(expected2.get(i), res.get(i)));
       }
@@ -3894,7 +3895,7 @@ public void testScanner_ExplicitColumns_FromFilesOnly_EnforceVersions() throws I
     region.flush(true);
 
     // Expected
-    List<Cell> expected = new ArrayList<>();
+    List<ExtendedCell> expected = new ArrayList<>();
     expected.add(kv13);
     expected.add(kv12);
     expected.add(kv23);
@@ -3904,9 +3905,9 @@ public void testScanner_ExplicitColumns_FromFilesOnly_EnforceVersions() throws I
     scan.addColumn(fam1, qf1);
     scan.addColumn(fam1, qf2);
     scan.readVersions(MAX_VERSIONS);
-    List<Cell> actual = new ArrayList<>();
+    List<ExtendedCell> actual = new ArrayList<>();
     try (InternalScanner scanner = region.getScanner(scan)) {
-      boolean hasNext = scanner.next(actual);
+      boolean hasNext = scanner.next((List) actual);
       assertEquals(false, hasNext);
 
       // Verify result
@@ -3968,7 +3969,7 @@ public void testScanner_ExplicitColumns_FromMemStoreAndFiles_EnforceVersions()
     region.put(put);
 
     // Expected
-    List<Cell> expected = new ArrayList<>();
+    List<ExtendedCell> expected = new ArrayList<>();
     expected.add(kv14);
     expected.add(kv13);
     expected.add(kv12);
@@ -3981,9 +3982,9 @@ public void testScanner_ExplicitColumns_FromMemStoreAndFiles_EnforceVersions()
     scan.addColumn(fam1, qf2);
     int versions = 3;
     scan.readVersions(versions);
-    List<Cell> actual = new ArrayList<>();
+    List<ExtendedCell> actual = new ArrayList<>();
     try (InternalScanner scanner = region.getScanner(scan)) {
-      boolean hasNext = scanner.next(actual);
+      boolean hasNext = scanner.next((List) actual);
       assertEquals(false, hasNext);
 
       // Verify result
@@ -4082,7 +4083,7 @@ public void testScanner_Wildcard_FromFilesOnly_EnforceVersions() throws IOExcept
     region.flush(true);
 
     // Expected
-    List<Cell> expected = new ArrayList<>();
+    List<ExtendedCell> expected = new ArrayList<>();
     expected.add(kv13);
     expected.add(kv12);
     expected.add(kv23);
@@ -4091,9 +4092,9 @@ public void testScanner_Wildcard_FromFilesOnly_EnforceVersions() throws IOExcept
     Scan scan = new Scan().withStartRow(row1);
     scan.addFamily(fam1);
     scan.readVersions(MAX_VERSIONS);
-    List<Cell> actual = new ArrayList<>();
+    List<ExtendedCell> actual = new ArrayList<>();
     try (InternalScanner scanner = region.getScanner(scan)) {
-      boolean hasNext = scanner.next(actual);
+      boolean hasNext = scanner.next((List) actual);
       assertEquals(false, hasNext);
 
       // Verify result
@@ -4207,9 +4208,9 @@ public void testScanner_Wildcard_FromMemStoreAndFiles_EnforceVersions() throws I
     Scan scan = new Scan().withStartRow(row1);
     int versions = 3;
     scan.readVersions(versions);
-    List<Cell> actual = new ArrayList<>();
+    List<ExtendedCell> actual = new ArrayList<>();
     try (InternalScanner scanner = region.getScanner(scan)) {
-      boolean hasNext = scanner.next(actual);
+      boolean hasNext = scanner.next((List) actual);
       assertEquals(false, hasNext);
 
       // Verify result
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHRegionServerBulkLoad.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHRegionServerBulkLoad.java
index 7b8fcf4e334c..6a410f953fe7 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHRegionServerBulkLoad.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHRegionServerBulkLoad.java
@@ -35,6 +35,7 @@
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
@@ -397,8 +398,8 @@ static class FindBulkHBaseListener extends TestWALActionsListener.DummyWALAction
     @Override
     public void visitLogEntryBeforeWrite(RegionInfo info, WALKey logKey, WALEdit logEdit) {
       for (Cell cell : logEdit.getCells()) {
-        KeyValue kv = KeyValueUtil.ensureKeyValue(cell);
-        for (Map.Entry entry : kv.toStringMap().entrySet()) {
+        KeyValue kv = KeyValueUtil.ensureKeyValue((ExtendedCell) cell);
+        for (Map.Entry<String, Object> entry : kv.toStringMap().entrySet()) {
           if (entry.getValue().equals(Bytes.toString(WALEdit.BULK_LOAD))) {
             found = true;
           }
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHStore.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHStore.java
index a3fa1bb65db8..13f2101c0040 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHStore.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHStore.java
@@ -2113,7 +2113,7 @@ public void testForceCloneOfBigCellForCellChunkImmutableSegment() throws Excepti
       (StoreScanner) store.getScanner(new Scan(new Get(rowKey1)), quals, seqId + 1);
     SegmentScanner segmentScanner = getTypeKeyValueScanner(storeScanner, SegmentScanner.class);
     ExtendedCell resultCell1 = segmentScanner.next();
-    assertTrue(CellUtil.equals(resultCell1, originalCell1));
+    assertTrue(PrivateCellUtil.equals(resultCell1, originalCell1));
     int cell1ChunkId = resultCell1.getChunkId();
     assertTrue(cell1ChunkId != ExtendedCell.CELL_NOT_BASED_ON_CHUNK);
     assertNull(segmentScanner.next());
@@ -2140,12 +2140,12 @@ public void testForceCloneOfBigCellForCellChunkImmutableSegment() throws Excepti
     // {@link CellChunkMap#getCell} we could not get the data chunk by chunkId.
     storeScanner = (StoreScanner) store.getScanner(new Scan(new Get(rowKey1)), quals, seqId + 1);
     segmentScanner = getTypeKeyValueScanner(storeScanner, SegmentScanner.class);
-    Cell newResultCell1 = segmentScanner.next();
+    ExtendedCell newResultCell1 = segmentScanner.next();
     assertTrue(newResultCell1 != resultCell1);
-    assertTrue(CellUtil.equals(newResultCell1, originalCell1));
+    assertTrue(PrivateCellUtil.equals(newResultCell1, originalCell1));
 
-    Cell resultCell2 = segmentScanner.next();
-    assertTrue(CellUtil.equals(resultCell2, originalCell2));
+    ExtendedCell resultCell2 = segmentScanner.next();
+    assertTrue(PrivateCellUtil.equals(resultCell2, originalCell2));
     assertNull(segmentScanner.next());
     segmentScanner.close();
     storeScanner.close();
@@ -2569,17 +2569,17 @@ public void testClearSnapshotGetScannerConcurrently() throws Exception {
         assertTrue(!memStoreLAB.chunks.isEmpty());
         assertTrue(!memStoreLAB.isReclaimed());
 
-        Cell cell1 = segmentScanner.next();
-        CellUtil.equals(smallCell, cell1);
-        Cell cell2 = segmentScanner.next();
-        CellUtil.equals(largeCell, cell2);
+        ExtendedCell cell1 = segmentScanner.next();
+        PrivateCellUtil.equals(smallCell, cell1);
+        ExtendedCell cell2 = segmentScanner.next();
+        PrivateCellUtil.equals(largeCell, cell2);
         assertNull(segmentScanner.next());
       } else {
-        List<Cell> results = new ArrayList<>();
-        storeScanner.next(results);
+        List<ExtendedCell> results = new ArrayList<>();
+        storeScanner.next((List) results);
         assertEquals(2, results.size());
-        CellUtil.equals(smallCell, results.get(0));
-        CellUtil.equals(largeCell, results.get(1));
+        PrivateCellUtil.equals(smallCell, results.get(0));
+        PrivateCellUtil.equals(largeCell, results.get(1));
       }
       assertTrue(exceptionRef.get() == null);
     } finally {
@@ -2712,11 +2712,11 @@ public void testMemoryLeakWhenFlushMemStoreRetrying() throws Exception {
       assertTrue(storeScanner.currentScanners.size() == 1);
       assertTrue(storeScanner.currentScanners.get(0) instanceof StoreFileScanner);
 
-      List<Cell> results = new ArrayList<>();
-      storeScanner.next(results);
+      List<ExtendedCell> results = new ArrayList<>();
+      storeScanner.next((List) results);
       assertEquals(2, results.size());
-      CellUtil.equals(smallCell, results.get(0));
-      CellUtil.equals(largeCell, results.get(1));
+      PrivateCellUtil.equals(smallCell, results.get(0));
+      PrivateCellUtil.equals(largeCell, results.get(1));
     } finally {
       if (storeScanner != null) {
         storeScanner.close();
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHStoreFile.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHStoreFile.java
index 824c195fd0f1..3db0b3d3f64c 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHStoreFile.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHStoreFile.java
@@ -45,6 +45,7 @@
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
 import org.apache.hadoop.hbase.HConstants;
@@ -1058,8 +1059,8 @@ public void testCacheOnWriteEvictOnClose() throws Exception {
     readerTwo.loadFileInfo();
     StoreFileScanner scannerTwo = getStoreFileScanner(readerTwo, true, true);
     scannerTwo.seek(KeyValue.LOWESTKEY);
-    Cell kv1 = null;
-    Cell kv2 = null;
+    ExtendedCell kv1 = null;
+    ExtendedCell kv2 = null;
     while ((kv1 = scannerOne.next()) != null) {
       kv2 = scannerTwo.next();
       assertTrue(kv1.equals(kv2));
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestKeepDeletes.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestKeepDeletes.java
index f9c332564d94..fdaa19dc3e5a 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestKeepDeletes.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestKeepDeletes.java
@@ -29,6 +29,7 @@
 import java.util.List;
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
 import org.apache.hadoop.hbase.HConstants;
@@ -349,8 +350,8 @@ public void testRawScan() throws Exception {
     s.setRaw(true);
     s.readAllVersions();
     InternalScanner scan = region.getScanner(s);
-    List<Cell> kvs = new ArrayList<>();
-    scan.next(kvs);
+    List<ExtendedCell> kvs = new ArrayList<>();
+    scan.next((List) kvs);
     assertEquals(8, kvs.size());
     assertTrue(PrivateCellUtil.isDeleteFamily(kvs.get(0)));
     assertArrayEquals(CellUtil.cloneValue(kvs.get(1)), T3);
@@ -369,7 +370,7 @@ public void testRawScan() throws Exception {
     s.setTimeRange(0, 1);
     scan = region.getScanner(s);
     kvs = new ArrayList<>();
-    scan.next(kvs);
+    scan.next((List) kvs);
     // nothing in this interval, not even delete markers
     assertTrue(kvs.isEmpty());
 
@@ -380,7 +381,7 @@ public void testRawScan() throws Exception {
     s.setTimeRange(0, ts + 2);
     scan = region.getScanner(s);
     kvs = new ArrayList<>();
-    scan.next(kvs);
+    scan.next((List) kvs);
     assertEquals(4, kvs.size());
     assertTrue(PrivateCellUtil.isDeleteFamily(kvs.get(0)));
     assertArrayEquals(CellUtil.cloneValue(kvs.get(1)), T1);
@@ -395,7 +396,7 @@ public void testRawScan() throws Exception {
     s.setTimeRange(ts + 3, ts + 5);
     scan = region.getScanner(s);
     kvs = new ArrayList<>();
-    scan.next(kvs);
+    scan.next((List) kvs);
     assertEquals(2, kvs.size());
     assertArrayEquals(CellUtil.cloneValue(kvs.get(0)), T3);
     assertTrue(CellUtil.isDelete(kvs.get(1)));
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestMultiColumnScanner.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestMultiColumnScanner.java
index 0f55805f6fd8..0db4175916df 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestMultiColumnScanner.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestMultiColumnScanner.java
@@ -36,6 +36,7 @@
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellComparatorImpl;
 import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.KeyValueTestUtil;
@@ -210,15 +211,15 @@ public void testMultiColumnScanner() throws IOException {
         }
 
         InternalScanner scanner = region.getScanner(scan);
-        List<Cell> results = new ArrayList<>();
+        List<ExtendedCell> results = new ArrayList<>();
 
         int kvPos = 0;
         int numResults = 0;
         String queryInfo = "columns queried: " + qualSet + " (columnBitMask=" + columnBitMask
           + "), maxVersions=" + maxVersions;
 
-        while (scanner.next(results) || results.size() > 0) {
-          for (Cell kv : results) {
+        while (scanner.next((List) results) || results.size() > 0) {
+          for (ExtendedCell kv : results) {
             while (
               kvPos < kvs.size()
                 && !matchesQuery(kvs.get(kvPos), qualSet, maxVersions, lastDelTimeMap)
@@ -236,7 +237,7 @@ public void testMultiColumnScanner() throws IOException {
               "Scanner returned additional key/value: " + kv + ", " + queryInfo + deleteInfo + ";",
               kvPos < kvs.size());
             assertTrue("Scanner returned wrong key/value; " + queryInfo + deleteInfo + ";",
-              PrivateCellUtil.equalsIgnoreMvccVersion(kvs.get(kvPos), (kv)));
+              PrivateCellUtil.equalsIgnoreMvccVersion(kvs.get(kvPos), kv));
             ++kvPos;
             ++numResults;
           }
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestReplicateToReplica.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestReplicateToReplica.java
index a3b4c9e0347f..253ca876bd34 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestReplicateToReplica.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestReplicateToReplica.java
@@ -40,7 +40,7 @@
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.hbase.CellScanner;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
 import org.apache.hadoop.hbase.HConstants;
@@ -251,7 +251,7 @@ private FlushResult flushPrimary() throws IOException {
 
   private void replicate(Pair<List<WAL.Entry>, CompletableFuture<Void>> pair) throws IOException {
     Pair<ReplicateWALEntryRequest,
-      CellScanner> params = ReplicationProtobufUtil.buildReplicateWALEntryRequest(
+      ExtendedCellScanner> params = ReplicationProtobufUtil.buildReplicateWALEntryRequest(
         pair.getFirst().toArray(new WAL.Entry[0]),
         secondary.getRegionInfo().getEncodedNameAsBytes(), null, null, null);
     for (WALEntry entry : params.getFirst().getEntryList()) {
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestStoreFileScannerWithTagCompression.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestStoreFileScannerWithTagCompression.java
index 67671fe12fef..e3ba4d85a3a9 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestStoreFileScannerWithTagCompression.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestStoreFileScannerWithTagCompression.java
@@ -26,7 +26,7 @@
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hbase.ArrayBackedTag;
-import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
 import org.apache.hadoop.hbase.KeyValue;
@@ -93,7 +93,7 @@ public void testReseek() throws Exception {
       // Now do reseek with empty KV to position to the beginning of the file
       KeyValue k = KeyValueUtil.createFirstOnRow(Bytes.toBytes("k2"));
       s.reseek(k);
-      Cell kv = s.next();
+      ExtendedCell kv = s.next();
       kv = s.next();
       kv = s.next();
       byte[] key5 = Bytes.toBytes("k5");
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestTags.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestTags.java
index 45b927c07afa..b04a0054276c 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestTags.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestTags.java
@@ -29,6 +29,8 @@
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellScanner;
 import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.ExtendedCell;
+import org.apache.hadoop.hbase.ExtendedCellScanner;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
 import org.apache.hadoop.hbase.HConstants;
@@ -489,7 +491,7 @@ public void testTagsWithAppendAndIncrement() throws Exception {
       TestCoprocessorForTags.checkTagPresence = true;
       ResultScanner scanner = table.getScanner(new Scan());
       Result result = scanner.next();
-      KeyValue kv = KeyValueUtil.ensureKeyValue(result.getColumnLatestCell(f, q));
+      KeyValue kv = KeyValueUtil.ensureKeyValue((ExtendedCell) result.getColumnLatestCell(f, q));
       List<Tag> tags = TestCoprocessorForTags.tags;
       assertEquals(3L, Bytes.toLong(kv.getValueArray(), kv.getValueOffset(), kv.getValueLength()));
       assertEquals(1, tags.size());
@@ -504,7 +506,7 @@ public void testTagsWithAppendAndIncrement() throws Exception {
       TestCoprocessorForTags.checkTagPresence = true;
       scanner = table.getScanner(new Scan());
       result = scanner.next();
-      kv = KeyValueUtil.ensureKeyValue(result.getColumnLatestCell(f, q));
+      kv = KeyValueUtil.ensureKeyValue((ExtendedCell) result.getColumnLatestCell(f, q));
       tags = TestCoprocessorForTags.tags;
       assertEquals(5L, Bytes.toLong(kv.getValueArray(), kv.getValueOffset(), kv.getValueLength()));
       assertEquals(2, tags.size());
@@ -529,7 +531,7 @@ public void testTagsWithAppendAndIncrement() throws Exception {
       TestCoprocessorForTags.checkTagPresence = true;
       scanner = table.getScanner(new Scan().withStartRow(row2));
       result = scanner.next();
-      kv = KeyValueUtil.ensureKeyValue(result.getColumnLatestCell(f, q));
+      kv = KeyValueUtil.ensureKeyValue((ExtendedCell) result.getColumnLatestCell(f, q));
       tags = TestCoprocessorForTags.tags;
       assertEquals(4L, Bytes.toLong(kv.getValueArray(), kv.getValueOffset(), kv.getValueLength()));
       assertEquals(1, tags.size());
@@ -549,7 +551,7 @@ public void testTagsWithAppendAndIncrement() throws Exception {
       TestCoprocessorForTags.checkTagPresence = true;
       scanner = table.getScanner(new Scan().withStartRow(row3));
       result = scanner.next();
-      kv = KeyValueUtil.ensureKeyValue(result.getColumnLatestCell(f, q));
+      kv = KeyValueUtil.ensureKeyValue((ExtendedCell) result.getColumnLatestCell(f, q));
       tags = TestCoprocessorForTags.tags;
       assertEquals(1, tags.size());
       assertEquals("tag1", Bytes.toString(Tag.cloneValue(tags.get(0))));
@@ -563,7 +565,7 @@ public void testTagsWithAppendAndIncrement() throws Exception {
       TestCoprocessorForTags.checkTagPresence = true;
       scanner = table.getScanner(new Scan().withStartRow(row3));
       result = scanner.next();
-      kv = KeyValueUtil.ensureKeyValue(result.getColumnLatestCell(f, q));
+      kv = KeyValueUtil.ensureKeyValue((ExtendedCell) result.getColumnLatestCell(f, q));
       tags = TestCoprocessorForTags.tags;
       assertEquals(2, tags.size());
       // We cannot assume the ordering of tags
@@ -587,7 +589,7 @@ public void testTagsWithAppendAndIncrement() throws Exception {
       TestCoprocessorForTags.checkTagPresence = true;
       scanner = table.getScanner(new Scan().withStartRow(row4));
       result = scanner.next();
-      kv = KeyValueUtil.ensureKeyValue(result.getColumnLatestCell(f, q));
+      kv = KeyValueUtil.ensureKeyValue((ExtendedCell) result.getColumnLatestCell(f, q));
       tags = TestCoprocessorForTags.tags;
       assertEquals(1, tags.size());
       assertEquals("tag2", Bytes.toString(Tag.cloneValue(tags.get(0))));
@@ -653,7 +655,7 @@ private void updateMutationAddingTags(final Mutation m) {
       if (attribute != null) {
         for (List<? extends Cell> edits : m.getFamilyCellMap().values()) {
           for (Cell cell : edits) {
-            KeyValue kv = KeyValueUtil.ensureKeyValue(cell);
+            KeyValue kv = KeyValueUtil.ensureKeyValue((ExtendedCell) cell);
             if (cf == null) {
               cf = CellUtil.cloneFamily(kv);
             }
@@ -696,9 +698,9 @@ public boolean postScannerNext(ObserverContext<RegionCoprocessorEnvironment> e,
         if (results.size() > 0) {
           // Check tag presence in the 1st cell in 1st Result
           Result result = results.get(0);
-          CellScanner cellScanner = result.cellScanner();
+          ExtendedCellScanner cellScanner = result.cellScanner();
           if (cellScanner.advance()) {
-            Cell cell = cellScanner.current();
+            ExtendedCell cell = cellScanner.current();
             tags = PrivateCellUtil.getTags(cell);
           }
         }
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/compactions/TestCompactor.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/compactions/TestCompactor.java
index 5359dec2e64d..028de5066c80 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/compactions/TestCompactor.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/compactions/TestCompactor.java
@@ -203,7 +203,9 @@ public Scanner(KeyValue... kvs) {
 
     @Override
     public boolean next(List<Cell> result, ScannerContext scannerContext) throws IOException {
-      if (kvs.isEmpty()) return false;
+      if (kvs.isEmpty()) {
+        return false;
+      }
       result.add(kvs.remove(0));
       return !kvs.isEmpty();
     }
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/replication/TestReplicationWithTags.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/replication/TestReplicationWithTags.java
index 484206ad8387..33efd51368bb 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/replication/TestReplicationWithTags.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/replication/TestReplicationWithTags.java
@@ -29,6 +29,7 @@
 import org.apache.hadoop.hbase.ArrayBackedTag;
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
@@ -219,7 +220,7 @@ public void prePut(final ObserverContext<RegionCoprocessorEnvironment> e, final
       if (attribute != null) {
         for (List<? extends Cell> edits : put.getFamilyCellMap().values()) {
           for (Cell cell : edits) {
-            KeyValue kv = KeyValueUtil.ensureKeyValue(cell);
+            KeyValue kv = KeyValueUtil.ensureKeyValue((ExtendedCell) cell);
             if (cf == null) {
               cf = CellUtil.cloneFamily(kv);
             }
@@ -257,7 +258,7 @@ public void postGetOp(ObserverContext<RegionCoprocessorEnvironment> e, Get get,
         // Check tag presence in the 1st cell in 1st Result
         if (!results.isEmpty()) {
           Cell cell = results.get(0);
-          TAGS = PrivateCellUtil.getTags(cell);
+          TAGS = PrivateCellUtil.getTags((ExtendedCell) cell);
         }
       }
     }
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/security/visibility/ExpAsStringVisibilityLabelServiceImpl.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/security/visibility/ExpAsStringVisibilityLabelServiceImpl.java
index 0b9a9d663e5a..f3fd0878f9a4 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/security/visibility/ExpAsStringVisibilityLabelServiceImpl.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/security/visibility/ExpAsStringVisibilityLabelServiceImpl.java
@@ -38,6 +38,7 @@
 import org.apache.hadoop.hbase.CellBuilder;
 import org.apache.hadoop.hbase.CellBuilderFactory;
 import org.apache.hadoop.hbase.CellBuilderType;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HConstants.OperationStatusCode;
 import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.Tag;
@@ -273,7 +274,9 @@ public boolean evaluate(Cell cell) throws IOException {
     final List<String> authLabelsFinal = authLabels;
     return new VisibilityExpEvaluator() {
       @Override
-      public boolean evaluate(Cell cell) throws IOException {
+      public boolean evaluate(Cell c) throws IOException {
+        assert c instanceof ExtendedCell;
+        ExtendedCell cell = (ExtendedCell) c;
         boolean visibilityTagPresent = false;
         // Save an object allocation where we can
         if (cell.getTagsLength() > 0) {
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/security/visibility/TestVisibilityLabelsReplication.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/security/visibility/TestVisibilityLabelsReplication.java
index dc313d414ae8..10ca33e38725 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/security/visibility/TestVisibilityLabelsReplication.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/security/visibility/TestVisibilityLabelsReplication.java
@@ -33,6 +33,7 @@
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellScanner;
 import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
@@ -292,7 +293,7 @@ protected static void doAssert(byte[] row, String visTag) throws Exception {
         (Bytes.equals(cell.getRowArray(), cell.getRowOffset(), cell.getRowLength(), row, 0,
           row.length))
       ) {
-        List<Tag> tags = PrivateCellUtil.getTags(cell);
+        List<Tag> tags = PrivateCellUtil.getTags((ExtendedCell) cell);
         for (Tag tag : tags) {
           if (tag.getType() == TagType.STRING_VIS_TAG_TYPE) {
             assertEquals(visTag, Tag.getValueAsString(tag));
@@ -418,14 +419,15 @@ public void prePut(ObserverContext<RegionCoprocessorEnvironment> e, Put m, WALEd
       if (attribute != null) {
         for (List<? extends Cell> edits : m.getFamilyCellMap().values()) {
           for (Cell cell : edits) {
-            KeyValue kv = KeyValueUtil.ensureKeyValue(cell);
+            KeyValue kv = KeyValueUtil.ensureKeyValue((ExtendedCell) cell);
             if (cf == null) {
               cf = CellUtil.cloneFamily(kv);
             }
             Tag tag = new ArrayBackedTag((byte) NON_VIS_TAG_TYPE, attribute);
-            List<Tag> tagList = new ArrayList<>(PrivateCellUtil.getTags(cell).size() + 1);
+            List<Tag> tagList =
+              new ArrayList<>(PrivateCellUtil.getTags((ExtendedCell) cell).size() + 1);
             tagList.add(tag);
-            tagList.addAll(PrivateCellUtil.getTags(cell));
+            tagList.addAll(PrivateCellUtil.getTags((ExtendedCell) cell));
             Cell newcell = PrivateCellUtil.createCell(kv, tagList);
             ((List<Cell>) updatedCells).add(newcell);
           }
@@ -452,7 +454,7 @@ public void postGetOp(ObserverContext<RegionCoprocessorEnvironment> e, Get get,
         // Check tag presence in the 1st cell in 1st Result
         if (!results.isEmpty()) {
           Cell cell = results.get(0);
-          tags = PrivateCellUtil.getTags(cell);
+          tags = PrivateCellUtil.getTags((ExtendedCell) cell);
         }
       }
     }
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/util/HFileTestUtil.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/util/HFileTestUtil.java
index 20f621fba61a..d017db6eb9bd 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/util/HFileTestUtil.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/util/HFileTestUtil.java
@@ -144,7 +144,8 @@ public static void verifyTags(Table table) throws IOException {
     ResultScanner s = table.getScanner(new Scan());
     for (Result r : s) {
       for (Cell c : r.listCells()) {
-        Optional<Tag> tag = PrivateCellUtil.getTag(c, TagType.MOB_TABLE_NAME_TAG_TYPE);
+        Optional<Tag> tag =
+          PrivateCellUtil.getTag((ExtendedCell) c, TagType.MOB_TABLE_NAME_TAG_TYPE);
         if (!tag.isPresent()) {
           fail(c.toString() + " has null tag");
           continue;
diff --git a/hbase-thrift/src/main/java/org/apache/hadoop/hbase/thrift2/ThriftUtilities.java b/hbase-thrift/src/main/java/org/apache/hadoop/hbase/thrift2/ThriftUtilities.java
index a02f944e12a7..53299dbab997 100644
--- a/hbase-thrift/src/main/java/org/apache/hadoop/hbase/thrift2/ThriftUtilities.java
+++ b/hbase-thrift/src/main/java/org/apache/hadoop/hbase/thrift2/ThriftUtilities.java
@@ -34,6 +34,7 @@
 import org.apache.hadoop.hbase.CellBuilderType;
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.CompareOperator;
+import org.apache.hadoop.hbase.ExtendedCell;
 import org.apache.hadoop.hbase.ExtendedCellBuilder;
 import org.apache.hadoop.hbase.ExtendedCellBuilderFactory;
 import org.apache.hadoop.hbase.HConstants;
@@ -55,6 +56,7 @@
 import org.apache.hadoop.hbase.client.Mutation;
 import org.apache.hadoop.hbase.client.OnlineLogRecord;
 import org.apache.hadoop.hbase.client.OperationWithAttributes;
+import org.apache.hadoop.hbase.client.PackagePrivateFieldAccessor;
 import org.apache.hadoop.hbase.client.Put;
 import org.apache.hadoop.hbase.client.RegionInfo;
 import org.apache.hadoop.hbase.client.Result;
@@ -220,14 +222,14 @@ public static List<Get> getsFromThrift(List<TGet> in) throws IOException {
    * @return converted result, returns an empty result if the input is <code>null</code>
    */
   public static TResult resultFromHBase(Result in) {
-    Cell[] raw = in.rawCells();
+    ExtendedCell[] raw = PackagePrivateFieldAccessor.getExtendedRawCells(in);
     TResult out = new TResult();
     byte[] row = in.getRow();
     if (row != null) {
       out.setRow(in.getRow());
     }
     List<TColumnValue> columnValues = new ArrayList<>(raw.length);
-    for (Cell kv : raw) {
+    for (ExtendedCell kv : raw) {
       TColumnValue col = new TColumnValue();
       col.setFamily(CellUtil.cloneFamily(kv));
       col.setQualifier(CellUtil.cloneQualifier(kv));
@@ -1309,9 +1311,10 @@ public static TPut putFromHBase(Put in) {
     if (in.getDurability() != Durability.USE_DEFAULT) {
       out.setDurability(durabilityFromHBase(in.getDurability()));
     }
-    for (Map.Entry<byte[], List<Cell>> entry : in.getFamilyCellMap().entrySet()) {
+    for (Map.Entry<byte[], List<ExtendedCell>> entry : PackagePrivateFieldAccessor
+      .getExtendedFamilyCellMap(in).entrySet()) {
       byte[] family = entry.getKey();
-      for (Cell cell : entry.getValue()) {
+      for (ExtendedCell cell : entry.getValue()) {
         TColumnValue columnValue = new TColumnValue();
         columnValue.setFamily(family).setQualifier(CellUtil.cloneQualifier(cell))
           .setType(cell.getType().getCode()).setTimestamp(cell.getTimestamp())
@@ -1372,9 +1375,10 @@ public static TAppend appendFromHBase(Append in) throws IOException {
     if (in.getDurability() != Durability.USE_DEFAULT) {
       out.setDurability(durabilityFromHBase(in.getDurability()));
     }
-    for (Map.Entry<byte[], List<Cell>> entry : in.getFamilyCellMap().entrySet()) {
+    for (Map.Entry<byte[], List<ExtendedCell>> entry : PackagePrivateFieldAccessor
+      .getExtendedFamilyCellMap(in).entrySet()) {
       byte[] family = entry.getKey();
-      for (Cell cell : entry.getValue()) {
+      for (ExtendedCell cell : entry.getValue()) {
         TColumnValue columnValue = new TColumnValue();
         columnValue.setFamily(family).setQualifier(CellUtil.cloneQualifier(cell))
           .setType(cell.getType().getCode()).setTimestamp(cell.getTimestamp())