HDDS-11484. Validate javadoc in CI (apache#7245)

.github/workflows/ci.yml

@@ -218,7 +218,7 @@ jobs:
           distribution: 'temurin'
           java-version: ${{ matrix.java }}
       - name: Compile Ozone using Java ${{ matrix.java }}
-        run: hadoop-ozone/dev-support/checks/build.sh -Pdist -Dskip.npx -Dskip.installnpx -Djavac.version=${{ matrix.java }} ${{ inputs.ratis_args }}
+        run: hadoop-ozone/dev-support/checks/build.sh -Pdist -Dskip.npx -Dskip.installnpx -Dmaven.javadoc.failOnWarnings=${{ matrix.java != 8 }} -Djavac.version=${{ matrix.java }} ${{ inputs.ratis_args }}
         env:
           OZONE_WITH_COVERAGE: false
           DEVELOCITY_ACCESS_KEY: ${{ secrets.GE_ACCESS_TOKEN }}

hadoop-hdds/client/src/main/java/org/apache/hadoop/hdds/scm/storage/ExtendedInputStream.java

@@ -75,7 +75,6 @@ public synchronized int read(ByteBuffer byteBuffer) throws IOException {
    * readWithStrategy implementation, as it will never be called by the tests.
    *
    * @param strategy
-   * @return
    * @throws IOException
    */
   protected abstract int readWithStrategy(ByteReaderStrategy strategy) throws

hadoop-hdds/client/src/main/java/org/apache/hadoop/ozone/client/io/ECBlockInputStream.java

@@ -152,7 +152,6 @@ protected int calculateExpectedDataBlocks(ECReplicationConfig rConfig) {
    * Using the current position, returns the index of the blockStream we should
    * be reading from. This is the index in the internal array holding the
    * stream reference. The block group index will be one greater than this.
-   * @return
    */
   protected int currentStreamIndex() {
     return (int)((position / ecChunkSize) % repConfig.getData());
@@ -206,7 +205,6 @@ protected BlockExtendedInputStream getOrOpenStream(int locationIndex) throws IOE
    * to the replicaIndex given based on the EC pipeline fetched from SCM.
    * @param replicaIndex
    * @param refreshFunc
-   * @return
    */
   protected Function<BlockID, BlockLocationInfo> ecPipelineRefreshFunction(
       int replicaIndex, Function<BlockID, BlockLocationInfo> refreshFunc) {
@@ -241,7 +239,6 @@ protected Function<BlockID, BlockLocationInfo> ecPipelineRefreshFunction(
    * potentially partial last stripe. Note that the internal block index is
    * numbered starting from 1.
    * @param index - Index number of the internal block, starting from 1
-   * @return
    */
   protected long internalBlockLength(int index) {
     long lastStripe = blockInfo.getLength() % stripeSize;
@@ -344,7 +341,6 @@ protected boolean shouldRetryFailedRead(int failedIndex) {
    * strategy buffer. This call may read from several internal BlockInputStreams
    * if there is sufficient space in the buffer.
    * @param strategy
-   * @return
    * @throws IOException
    */
   @Override
@@ -409,7 +405,6 @@ protected void seekStreamIfNecessary(BlockExtendedInputStream stream,
    * group length.
    * @param stream Stream to read from
    * @param strategy The ReaderStrategy to read data into
-   * @return
    * @throws IOException
    */
   private int readFromStream(BlockExtendedInputStream stream,

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/HddsUtils.java

@@ -650,7 +650,7 @@ public static File createDir(String dirPath) {
    * Utility string formatter method to display SCM roles.
    *
    * @param nodes
-   * @return
+   * @return String
    */
   public static String format(List<String> nodes) {
     StringBuilder sb = new StringBuilder();
@@ -680,7 +680,8 @@ public static int roundupMb(long bytes) {
 
   /**
    * Unwrap exception to check if it is some kind of access control problem
-   * ({@link AccessControlException} or {@link SecretManager.InvalidToken})
+   * ({@link org.apache.hadoop.security.AccessControlException} or
+   * {@link org.apache.hadoop.security.token.SecretManager.InvalidToken})
    * or a RpcException.
    */
   public static Throwable getUnwrappedException(Exception ex) {

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/client/DecommissionUtils.java

@@ -97,7 +97,6 @@ public static JsonNode getBeansJsonNode(String metricsJson) throws IOException {
    * Returns the number of decommissioning nodes.
    *
    * @param jsonNode
-   * @return
    */
   public static int getNumDecomNodes(JsonNode jsonNode) {
     int numDecomNodes;
@@ -118,7 +117,6 @@ public static int getNumDecomNodes(JsonNode jsonNode) {
    * @param numDecomNodes
    * @param countsMap
    * @param errMsg
-   * @return
    * @throws IOException
    */
   @Nullable

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/client/ScmClient.java

@@ -396,7 +396,6 @@ StartContainerBalancerResponseProto startContainerBalancer(
    * Force generates new secret keys (rotate).
    *
    * @param force boolean flag that forcefully rotates the key on demand
-   * @return
    * @throws IOException
    */
   boolean rotateSecretKeys(boolean force) throws IOException;

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/container/ReplicationManagerReport.java

@@ -146,7 +146,6 @@ public long getReportTimeStamp() {
 
   /**
    * Return a map of all stats and their value as a long.
-   * @return
    */
   public Map<String, Long> getStats() {
     Map<String, Long> result = new HashMap<>();
@@ -159,7 +158,6 @@ public Map<String, Long> getStats() {
   /**
    * Return a map of all samples, with the stat as the key and the samples
    * for the stat as a List of Long.
-   * @return
    */
   public Map<String, List<Long>> getSamples() {
     Map<String, List<Long>> result = new HashMap<>();

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/ha/SCMNodeInfo.java

@@ -67,7 +67,6 @@ public class SCMNodeInfo {
   /**
    * Build SCM Node information from configuration.
    * @param conf
-   * @return
    */
   public static List<SCMNodeInfo> buildNodeInfo(ConfigurationSource conf) {
 

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/net/InnerNodeImpl.java

@@ -307,10 +307,13 @@ public void remove(Node node) {
    * @param loc string location of a node. If loc starts with "/", it's a
    *            absolute path, otherwise a relative path. Following examples
    *            are all accepted,
+   *            <pre>
+   *            {@code
    *            1.  /dc1/rm1/rack1          -> an inner node
    *            2.  /dc1/rm1/rack1/node1    -> a leaf node
    *            3.  rack1/node1             -> a relative path to this node
-   *
+   *            }
+   *            </pre>
    * @return null if the node is not found
    */
   @Override

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/pipeline/Pipeline.java

@@ -243,7 +243,6 @@ public int getReplicaIndex(DatanodeDetails dn) {
 
   /**
    * Get the replicaIndex Map.
-   * @return
    */
   public Map<DatanodeDetails, Integer> getReplicaIndexes() {
     return this.getNodes().stream().collect(Collectors.toMap(Function.identity(), this::getReplicaIndex));

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/server/ServerUtils.java

@@ -131,7 +131,7 @@ public static InetSocketAddress updateListenAddress(OzoneConfiguration conf,
    * Fall back to OZONE_METADATA_DIRS if not defined.
    *
    * @param conf
-   * @return
+   * @return File
    */
   public static File getScmDbDir(ConfigurationSource conf) {
     File metadataDir = getDirectoryFromConfig(conf,

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/utils/LeakDetector.java

@@ -31,7 +31,6 @@
 /**
  * Simple general resource leak detector using {@link ReferenceQueue} and {@link java.lang.ref.WeakReference} to
  * observe resource object life-cycle and assert proper resource closure before they are GCed.
- *
  * <p>
  * Example usage:
  *
@@ -43,16 +42,18 @@
  *      // report leaks, don't refer to the original object (MyResource) here.
  *      System.out.println("MyResource is not closed before being discarded.");
  *   });
- *
- *   @Override
+ * }
+ * }
+ * </pre>
+ * <pre>
+ *   {@code @Override
  *   public void close() {
  *     // proper resources cleanup...
  *     // inform tracker that this object is closed properly.
  *     leakTracker.close();
  *   }
- * }
- *
- * }</pre>
+ *  }
+ * </pre>
  */
 public class LeakDetector {
   private static final Logger LOG = LoggerFactory.getLogger(LeakDetector.class);

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/utils/db/DelegatedCodec.java

@@ -23,9 +23,9 @@
 import java.io.IOException;
 
 /**
- * A {@link Codec} to serialize/deserialize objects by delegation.
+ * A {@link org.apache.hadoop.hdds.utils.db.Codec} to serialize/deserialize objects by delegation.
  *
- * @param <T>        The object type of this {@link Codec}.
+ * @param <T>        The object type of this {@link org.apache.hadoop.hdds.utils.db.Codec}.
  * @param <DELEGATE> The object type of the {@link #delegate}.
  */
 public class DelegatedCodec<T, DELEGATE> implements Codec<T> {
@@ -53,8 +53,8 @@ public enum CopyType {
    * Construct a {@link Codec} using the given delegate.
    *
    * @param delegate the delegate {@link Codec}
-   * @param forward a function to convert {@link DELEGATE} to {@link T}.
-   * @param backward a function to convert {@link T} back to {@link DELEGATE}.
+   * @param forward a function to convert {@code DELEGATE} to {@code T}.
+   * @param backward a function to convert {@code T} back to {@code DELEGATE}.
    * @param copyType How to {@link #copyObject(Object)}?
    */
   public DelegatedCodec(Codec<DELEGATE> delegate,

hadoop-hdds/common/src/main/java/org/apache/hadoop/ozone/common/ChunkBuffer.java

@@ -39,8 +39,7 @@ static ChunkBuffer allocate(int capacity) {
     return allocate(capacity, 0);
   }
 
-  /**
-   * Similar to {@link ByteBuffer#allocate(int)}
+  /** Similar to {@link ByteBuffer#allocate(int)}
    * except that it can specify the increment.
    *
    * @param increment

hadoop-hdds/common/src/main/java/org/apache/hadoop/ozone/container/common/helpers/ChunkInfoList.java

@@ -27,7 +27,7 @@
 
 /**
  * Helper class to convert between protobuf lists and Java lists of
- * {@link ContainerProtos.ChunkInfo} objects.
+ * {@link org.apache.hadoop.hdds.protocol.datanode.proto.ContainerProtos.ChunkInfo} objects.
  * <p>
  * This class is immutable.
  */
@@ -49,7 +49,7 @@ public ChunkInfoList(List<ContainerProtos.ChunkInfo> chunks) {
   }
 
   /**
-   * @return A new {@link ChunkInfoList} created from protobuf data.
+   * @return A new {@link #ChunkInfoList} created from protobuf data.
    */
   public static ChunkInfoList getFromProtoBuf(
           ContainerProtos.ChunkInfoList chunksProto) {

hadoop-hdds/common/src/main/java/org/apache/hadoop/ozone/upgrade/LayoutVersionInstanceFactory.java

@@ -69,7 +69,7 @@ public class LayoutVersionInstanceFactory<T> {
   /**
    * Register an instance with a given factory key (key + version).
    * For safety reasons we dont allow (1) re-registering, (2) registering an
-   * instance with version > SLV.
+   * instance with version &gt; SLV.
    *
    * @param lvm LayoutVersionManager
    * @param key VersionFactoryKey key to associate with instance.
@@ -136,13 +136,15 @@ private boolean isValid(LayoutVersionManager lvm, int version) {
   }
 
   /**
+   * <pre>
    * From the list of versioned instances for a given "key", this
    * returns the "floor" value corresponding to the given version.
-   * For example, if we have key = "CreateKey",  entry -> [(1, CreateKeyV1),
-   * (3, CreateKeyV2), and if the passed in key = CreateKey and version = 2, we
+   * For example, if we have key = "CreateKey",  entry -&gt; [(1, CreateKeyV1),
+   * (3, CreateKeyV2), and if the passed in key = CreateKey &amp; version = 2, we
    * return CreateKeyV1.
    * Since this is a priority queue based implementation, we use a O(1) peek()
    * lookup to get the current valid version.
+   * </pre>
    * @param lvm LayoutVersionManager
    * @param key Key and Version.
    * @return instance.

hadoop-hdds/common/src/main/java/org/apache/hadoop/ozone/upgrade/LayoutVersionManager.java

@@ -74,7 +74,6 @@ public interface LayoutVersionManager {
   /**
    * Generic API for returning a registered handler for a given type.
    * @param type String type
-   * @return
    */
   default Object getHandler(String type) {
     return null;

hadoop-hdds/common/src/main/java/org/apache/hadoop/ozone/upgrade/UpgradeFinalizer.java

@@ -50,14 +50,14 @@ public interface UpgradeFinalizer<T> {
    * Represents the current state in which the service is with regards to
    * finalization after an upgrade.
    * The state transitions are the following:
-   * ALREADY_FINALIZED - no entry no exit from this status without restart.
+   * {@code ALREADY_FINALIZED} - no entry no exit from this status without restart.
    * After an upgrade:
-   * FINALIZATION_REQUIRED -(finalize)-> STARTING_FINALIZATION
-   * -> FINALIZATION_IN_PROGRESS -> FINALIZATION_DONE from finalization done
+   * {@code FINALIZATION_REQUIRED -(finalize)-> STARTING_FINALIZATION
+   * -> FINALIZATION_IN_PROGRESS -> FINALIZATION_DONE} from finalization done
    * there is no more move possible, after a restart the service can end up in:
-   * - FINALIZATION_REQUIRED, if the finalization failed and have not reached
-   * FINALIZATION_DONE,
-   * - or it can be ALREADY_FINALIZED if the finalization was successfully done.
+   * {@code FINALIZATION_REQUIRED}, if the finalization failed and have not reached
+   * {@code FINALIZATION_DONE},
+   * - or it can be {@code ALREADY_FINALIZED} if the finalization was successfully done.
    */
   enum Status {
     ALREADY_FINALIZED,

hadoop-hdds/common/src/main/java/org/apache/hadoop/ozone/upgrade/VersionFactoryKey.java

@@ -20,7 +20,7 @@
 
 /**
  * "Key" element to the Version specific instance factory. Currently it has 2
- * dimensions -> a 'key' string and a version. This is to support a factory
+ * dimensions -> a 'key' string and a version. This is to support a factory
  * which returns an instance for a given "key" and "version".
  */
 public class VersionFactoryKey {

hadoop-hdds/config/src/main/java/org/apache/hadoop/hdds/conf/ConfigurationSource.java

@@ -108,7 +108,7 @@ default String[] getTrimmedStrings(String name) {
   /**
    * Gets the configuration entries where the key contains the prefix. This
    * method will strip the prefix from the key in the return Map.
-   * Example: somePrefix.key->value will be key->value in the returned map.
+   * Example: {@code somePrefix.key->value} will be {@code key->value} in the returned map.
    * @param keyPrefix Prefix to search.
    * @return Map containing keys that match and their values.
    */

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/common/impl/OpenContainerBlockMap.java

@@ -35,7 +35,7 @@
 /**
  * Map: containerId {@literal ->} (localId {@literal ->} {@link BlockData}).
  * The outer container map does not entail locking for a better performance.
- * The inner {@link BlockDataMap} is synchronized.
+ * The inner {@code BlockDataMap} is synchronized.
  *
  * This class will maintain list of open keys per container when closeContainer
  * command comes, it should autocommit all open keys of a open container before

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/common/interfaces/ContainerDeletionChoosingPolicyTemplate.java

@@ -90,7 +90,7 @@ public final List<ContainerBlockInfo> chooseContainerForBlockDeletion(
   /**
    * Abstract step for ordering the container data to be deleted.
    * Subclass need to implement the concrete ordering implementation
-   * in descending order (more prioritized -> less prioritized)
+   * in descending order (more prioritized -&gt; less prioritized)
    * @param candidateContainers candidate containers to be ordered
    */
   protected abstract void orderByDescendingPriority(

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/common/interfaces/ContainerDispatcher.java

@@ -75,7 +75,6 @@ void validateContainerCommand(
   /**
    * Returns the handler for the specified containerType.
    * @param containerType
-   * @return
    */
   Handler getHandler(ContainerProtos.ContainerType containerType);
 

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/common/transport/server/ratis/ContainerStateMachine.java

@@ -705,9 +705,9 @@ private ExecutorService getChunkExecutor(WriteChunkRequestProto req) {
   }
 
   /**
-   * {@link #writeStateMachineData(ContainerCommandRequestProto, long, long, long)}
+   * {@link #writeStateMachineData}
    * calls are not synchronized with each other
-   * and also with {@link #applyTransaction(TransactionContext)}.
+   * and also with {@code applyTransaction(TransactionContext)}.
    */
   @Override
   public CompletableFuture<Message> write(LogEntryProto entry, TransactionContext trx) {

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/common/volume/VolumeInfo.java

@@ -57,7 +57,7 @@
  *              |     fsAvail      |-------other-----------|
  * |<-                   fsCapacity                      ->|
  * }</pre>
- *
+ * <pre>
  * What we could directly get from local fs:
  *     fsCapacity, fsAvail, (fsUsed = fsCapacity - fsAvail)
  * We could get from config:
@@ -80,13 +80,13 @@
  * then we should use DedicatedDiskSpaceUsage for
  * `hdds.datanode.du.factory.classname`,
  * Then it is much simpler, since we don't care about other usage:
- * <pre>
  * {@code
  *  |----used----|             (avail)/fsAvail              |
  *  |<-              capacity/fsCapacity                  ->|
- *  }
- * </pre>
+ * }
+ *
  *  We have avail == fsAvail.
+ *  </pre>
  */
 public final class VolumeInfo {
 
@@ -157,14 +157,14 @@ public long getCapacity() {
   }
 
   /**
-   * Calculate available space use method A.
    * <pre>
    * {@code
+   * Calculate available space use method A.
    * |----used----|   (avail)   |++++++++reserved++++++++|
    * |<-     capacity         ->|
-   * }
-   *</pre>
    * A) avail = capacity - used
+   * }
+   * </pre>
    */
   public long getAvailable() {
     return usage.getAvailable();