Style: Replace Arrays.asList with Collections.singletonList

aws/src/test/java/org/apache/iceberg/aws/s3/signer/TestS3SignRequestParser.java

@@ -21,6 +21,7 @@
 import com.fasterxml.jackson.databind.JsonNode;
 import java.net.URI;
 import java.util.Arrays;
+import java.util.Collections;
 import org.apache.iceberg.relocated.com.google.common.collect.ImmutableMap;
 import org.assertj.core.api.Assertions;
 import org.junit.jupiter.api.Test;
@@ -122,9 +123,9 @@ public void roundTripSerde() {
                     "amz-sdk-request",
                     Arrays.asList("attempt=1", "max=4"),
                     "Content-Length",
-                    Arrays.asList("191"),
+                    Collections.singletonList("191"),
                     "Content-Type",
-                    Arrays.asList("application/json"),
+                    Collections.singletonList("application/json"),
                     "User-Agent",
                     Arrays.asList("aws-sdk-java/2.20.18", "Linux/5.4.0-126")))
             .build();
@@ -158,9 +159,9 @@ public void roundTripSerdeWithProperties() {
                     "amz-sdk-request",
                     Arrays.asList("attempt=1", "max=4"),
                     "Content-Length",
-                    Arrays.asList("191"),
+                    Collections.singletonList("191"),
                     "Content-Type",
-                    Arrays.asList("application/json"),
+                    Collections.singletonList("application/json"),
                     "User-Agent",
                     Arrays.asList("aws-sdk-java/2.20.18", "Linux/5.4.0-126")))
             .properties(ImmutableMap.of("k1", "v1"))
@@ -198,9 +199,9 @@ public void roundTripWithBody() {
                     "amz-sdk-request",
                     Arrays.asList("attempt=1", "max=4"),
                     "Content-Length",
-                    Arrays.asList("191"),
+                    Collections.singletonList("191"),
                     "Content-Type",
-                    Arrays.asList("application/json"),
+                    Collections.singletonList("application/json"),
                     "User-Agent",
                     Arrays.asList("aws-sdk-java/2.20.18", "Linux/5.4.0-126")))
             .properties(ImmutableMap.of("k1", "v1"))

aws/src/test/java/org/apache/iceberg/aws/s3/signer/TestS3SignResponseParser.java

@@ -21,6 +21,7 @@
 import com.fasterxml.jackson.databind.JsonNode;
 import java.net.URI;
 import java.util.Arrays;
+import java.util.Collections;
 import org.apache.iceberg.relocated.com.google.common.collect.ImmutableMap;
 import org.assertj.core.api.Assertions;
 import org.junit.jupiter.api.Test;
@@ -70,9 +71,9 @@ public void roundTripSerde() {
                     "amz-sdk-request",
                     Arrays.asList("attempt=1", "max=4"),
                     "Content-Length",
-                    Arrays.asList("191"),
+                    Collections.singletonList("191"),
                     "Content-Type",
-                    Arrays.asList("application/json"),
+                    Collections.singletonList("application/json"),
                     "User-Agent",
                     Arrays.asList("aws-sdk-java/2.20.18", "Linux/5.4.0-126")))
             .build();

core/src/main/java/org/apache/iceberg/BaseRewriteManifests.java

@@ -22,8 +22,8 @@
 import static org.apache.iceberg.TableProperties.MANIFEST_TARGET_SIZE_BYTES_DEFAULT;
 
 import java.io.IOException;
-import java.util.Arrays;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -247,7 +247,7 @@ private void performRewrite(List<ManifestFile> currentManifests) {
                   rewrittenManifests.add(manifest);
                   try (ManifestReader<DataFile> reader =
                       ManifestFiles.read(manifest, ops.io(), ops.current().specsById())
-                          .select(Arrays.asList("*"))) {
+                          .select(Collections.singletonList("*"))) {
                     reader
                         .liveEntries()
                         .forEach(

core/src/test/java/org/apache/iceberg/ScanTestBase.java

@@ -23,7 +23,7 @@
 
 import java.io.File;
 import java.io.IOException;
-import java.util.Arrays;
+import java.util.Collections;
 import java.util.concurrent.Executors;
 import java.util.concurrent.atomic.AtomicInteger;
 import org.apache.iceberg.expressions.Expression;
@@ -56,7 +56,7 @@ public ScanTestBase(int formatVersion) {
 
   @Test
   public void testTableScanHonorsSelect() {
-    ScanT scan = newScan().select(Arrays.asList("id"));
+    ScanT scan = newScan().select(Collections.singletonList("id"));
 
     Schema expectedSchema = new Schema(required(1, "id", Types.IntegerType.get()));
 
@@ -69,20 +69,20 @@ public void testTableScanHonorsSelect() {
   @Test
   public void testTableBothProjectAndSelect() {
     Assertions.assertThatThrownBy(
-            () -> newScan().select(Arrays.asList("id")).project(SCHEMA.select("data")))
+            () -> newScan().select(Collections.singletonList("id")).project(SCHEMA.select("data")))
         .isInstanceOf(IllegalStateException.class)
         .hasMessage("Cannot set projection schema when columns are selected");
     Assertions.assertThatThrownBy(
-            () -> newScan().project(SCHEMA.select("data")).select(Arrays.asList("id")))
+            () -> newScan().project(SCHEMA.select("data")).select(Collections.singletonList("id")))
         .isInstanceOf(IllegalStateException.class)
         .hasMessage("Cannot select columns when projection schema is set");
   }
 
   @Test
   public void testTableScanHonorsSelectWithoutCaseSensitivity() {
-    ScanT scan1 = newScan().caseSensitive(false).select(Arrays.asList("ID"));
+    ScanT scan1 = newScan().caseSensitive(false).select(Collections.singletonList("ID"));
     // order of refinements shouldn't matter
-    ScanT scan2 = newScan().select(Arrays.asList("ID")).caseSensitive(false);
+    ScanT scan2 = newScan().select(Collections.singletonList("ID")).caseSensitive(false);
 
     Schema expectedSchema = new Schema(required(1, "id", Types.IntegerType.get()));
 

core/src/test/java/org/apache/iceberg/TestContentFileParser.java

@@ -21,6 +21,7 @@
 import com.fasterxml.jackson.databind.JsonNode;
 import java.nio.ByteBuffer;
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.stream.Stream;
 import org.apache.iceberg.relocated.com.google.common.collect.ImmutableMap;
 import org.apache.iceberg.types.Comparators;
@@ -270,7 +271,7 @@ private static DeleteFile deleteFileWithAllOptional(PartitionSpec spec) {
         metrics,
         new int[] {3},
         1,
-        Arrays.asList(128L),
+        Collections.singletonList(128L),
         ByteBuffer.wrap(new byte[16]));
   }
 

flink/v1.15/flink/src/test/java/org/apache/iceberg/flink/source/enumerator/TestContinuousIcebergEnumerator.java

@@ -18,7 +18,6 @@
  */
 package org.apache.iceberg.flink.source.enumerator;
 
-import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
@@ -173,7 +172,7 @@ public void testThrottlingDiscovery() throws Exception {
     enumerator.handleSourceEvent(2, new SplitRequestEvent());
 
     // add splits[0] to the planner for next discovery
-    splitPlanner.addSplits(Arrays.asList(splits.get(0)));
+    splitPlanner.addSplits(Collections.singletonList(splits.get(0)));
     enumeratorContext.triggerAllActions();
 
     // because discovered split was assigned to reader, pending splits should be empty
@@ -185,7 +184,7 @@ public void testThrottlingDiscovery() throws Exception {
     // add the remaining 9 splits (one for every snapshot)
     // run discovery cycles while reader-2 still processing the splits[0]
     for (int i = 1; i < 10; ++i) {
-      splitPlanner.addSplits(Arrays.asList(splits.get(i)));
+      splitPlanner.addSplits(Collections.singletonList(splits.get(i)));
       enumeratorContext.triggerAllActions();
     }
 
@@ -196,7 +195,8 @@ public void testThrottlingDiscovery() throws Exception {
         splits.subList(0, 1), enumeratorContext.getSplitAssignments().get(2).getAssignedSplits());
 
     // now reader-2 finished splits[0]
-    enumerator.handleSourceEvent(2, new SplitRequestEvent(Arrays.asList(splits.get(0).splitId())));
+    enumerator.handleSourceEvent(
+        2, new SplitRequestEvent(Collections.singletonList(splits.get(0).splitId())));
     enumeratorContext.triggerAllActions();
     // still have 3 pending splits. After assigned splits[1] to reader-2, one more split was
     // discovered and added.
@@ -217,7 +217,8 @@ public void testThrottlingDiscovery() throws Exception {
         splits.subList(0, 2), enumeratorContext.getSplitAssignments().get(2).getAssignedSplits());
 
     // now reader-2 finished splits[1]
-    enumerator.handleSourceEvent(2, new SplitRequestEvent(Arrays.asList(splits.get(1).splitId())));
+    enumerator.handleSourceEvent(
+        2, new SplitRequestEvent(Collections.singletonList(splits.get(1).splitId())));
     enumeratorContext.triggerAllActions();
     // still have 3 pending splits. After assigned new splits[2] to reader-2, one more split was
     // discovered and added.

flink/v1.15/flink/src/test/java/org/apache/iceberg/flink/source/reader/TestIcebergSourceReader.java

@@ -132,7 +132,7 @@ private void testOneSplitFetcher(
         ReaderUtil.createCombinedScanTask(
             recordBatchList, TEMPORARY_FOLDER, FileFormat.PARQUET, appenderFactory);
     IcebergSourceSplit split = IcebergSourceSplit.fromCombinedScanTask(task);
-    reader.addSplits(Arrays.asList(split));
+    reader.addSplits(Collections.singletonList(split));
 
     while (readerOutput.getEmittedRecords().size() < expectedCount) {
       reader.pollNext(readerOutput);

flink/v1.16/flink/src/test/java/org/apache/iceberg/flink/source/reader/TestIcebergSourceReader.java

@@ -132,7 +132,7 @@ private void testOneSplitFetcher(
         ReaderUtil.createCombinedScanTask(
             recordBatchList, TEMPORARY_FOLDER, FileFormat.PARQUET, appenderFactory);
     IcebergSourceSplit split = IcebergSourceSplit.fromCombinedScanTask(task);
-    reader.addSplits(Arrays.asList(split));
+    reader.addSplits(Collections.singletonList(split));
 
     while (readerOutput.getEmittedRecords().size() < expectedCount) {
       reader.pollNext(readerOutput);

flink/v1.17/flink/src/test/java/org/apache/iceberg/flink/source/reader/TestIcebergSourceReader.java

@@ -132,7 +132,7 @@ private void testOneSplitFetcher(
         ReaderUtil.createCombinedScanTask(
             recordBatchList, TEMPORARY_FOLDER, FileFormat.PARQUET, appenderFactory);
     IcebergSourceSplit split = IcebergSourceSplit.fromCombinedScanTask(task);
-    reader.addSplits(Arrays.asList(split));
+    reader.addSplits(Collections.singletonList(split));
 
     while (readerOutput.getEmittedRecords().size() < expectedCount) {
       reader.pollNext(readerOutput);

hive-metastore/src/test/java/org/apache/iceberg/hive/TestHiveSchemaUtil.java

@@ -23,6 +23,7 @@
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
 
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 import java.util.stream.Collectors;
 import org.apache.hadoop.hive.metastore.api.FieldSchema;
@@ -147,7 +148,9 @@ public void testSchemaConvertToIcebergSchemaForEveryPrimitiveType() {
   public void testNotSupportedTypes() {
     for (FieldSchema notSupportedField : getNotSupportedFieldSchemas()) {
       assertThatThrownBy(
-              () -> HiveSchemaUtil.convert(Lists.newArrayList(Arrays.asList(notSupportedField))))
+              () ->
+                  HiveSchemaUtil.convert(
+                      Lists.newArrayList(Collections.singletonList(notSupportedField))))
           .isInstanceOf(IllegalArgumentException.class)
           .hasMessageStartingWith("Unsupported Hive type");
     }
@@ -197,7 +200,7 @@ public void testConversionWithoutLastComment() {
             Arrays.asList(
                 TypeInfoUtils.getTypeInfoFromTypeString(serdeConstants.BIGINT_TYPE_NAME),
                 TypeInfoUtils.getTypeInfoFromTypeString(serdeConstants.STRING_TYPE_NAME)),
-            Arrays.asList("customer comment"));
+            Collections.singletonList("customer comment"));
 
     assertThat(schema.asStruct()).isEqualTo(expected.asStruct());
   }