Fix all inspection errors currently reported.

api/src/test/java/io/druid/timeline/DataSegmentTest.java

@@ -23,7 +23,6 @@
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
-import com.google.common.collect.Lists;
 import com.google.common.collect.RangeSet;
 import com.google.common.collect.Sets;
 import io.druid.TestObjectMapper;
@@ -40,6 +39,7 @@
 import org.junit.Before;
 import org.junit.Test;
 
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
@@ -238,7 +238,7 @@ public void testBucketMonthComparator()
         makeDataSegment("test2", "2011-02-02/2011-02-03", "a"),
     };
 
-    List<DataSegment> shuffled = Lists.newArrayList(sortedOrder);
+    List<DataSegment> shuffled = new ArrayList<>(Arrays.asList(sortedOrder));
     Collections.shuffle(shuffled);
 
     Set<DataSegment> theSet = Sets.newTreeSet(DataSegment.bucketMonthComparator());

benchmarks/src/main/java/io/druid/benchmark/query/timecompare/TimeCompareBenchmark.java

@@ -22,7 +22,6 @@
 import com.fasterxml.jackson.databind.InjectableValues;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.google.common.collect.Lists;
-import com.google.common.collect.Maps;
 import com.google.common.io.Files;
 import io.druid.benchmark.datagen.BenchmarkDataGenerator;
 import io.druid.benchmark.datagen.BenchmarkSchemaInfo;
@@ -96,6 +95,7 @@
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collections;
+import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
@@ -117,7 +117,7 @@ public class TimeCompareBenchmark
   @Param({"100"})
   private int threshold;
 
-  protected static final Map<String, String> scriptDoubleSum = Maps.newHashMap();
+  protected static final Map<String, String> scriptDoubleSum = new HashMap<>();
   static {
     scriptDoubleSum.put("fnAggregate", "function aggregate(current, a) { return current + a }");
     scriptDoubleSum.put("fnReset", "function reset() { return 0 }");
@@ -427,10 +427,7 @@ private IncrementalIndex makeIncIndex()
   @OutputTimeUnit(TimeUnit.MICROSECONDS)
   public void queryMultiQueryableIndexTopN(Blackhole blackhole)
   {
-    Sequence<Result<TopNResultValue>> queryResult = topNRunner.run(
-        QueryPlus.wrap(topNQuery),
-        Maps.<String, Object>newHashMap()
-    );
+    Sequence<Result<TopNResultValue>> queryResult = topNRunner.run(QueryPlus.wrap(topNQuery), new HashMap<>());
     List<Result<TopNResultValue>> results = queryResult.toList();
 
     for (Result<TopNResultValue> result : results) {
@@ -446,7 +443,7 @@ public void queryMultiQueryableIndexTimeseries(Blackhole blackhole)
   {
     Sequence<Result<TimeseriesResultValue>> queryResult = timeseriesRunner.run(
         QueryPlus.wrap(timeseriesQuery),
-        Maps.<String, Object>newHashMap()
+        new HashMap<>()
     );
     List<Result<TimeseriesResultValue>> results = queryResult.toList();
 

indexing-service/src/main/java/io/druid/indexing/common/task/batch/parallel/ParallelIndexSupervisorTask.java

@@ -268,7 +268,7 @@ private TaskStatus runParallel(TaskToolbox toolbox) throws Exception
     return TaskStatus.fromCode(getId(), runner.run());
   }
 
-  private TaskStatus runSequential(TaskToolbox toolbox) throws Exception
+  private TaskStatus runSequential(TaskToolbox toolbox)
   {
     return new IndexTask(
         getId(),

indexing-service/src/test/java/io/druid/indexing/overlord/autoscaling/EC2AutoScalerTest.java

@@ -117,7 +117,9 @@ public void testScale()
     EasyMock.expect(runInstancesResult.getReservation()).andReturn(reservation).atLeastOnce();
     EasyMock.replay(runInstancesResult);
 
-    EasyMock.expect(describeInstancesResult.getReservations()).andReturn(Collections.singletonList(reservation)).atLeastOnce();
+    EasyMock.expect(describeInstancesResult.getReservations())
+            .andReturn(Collections.singletonList(reservation))
+            .atLeastOnce();
     EasyMock.replay(describeInstancesResult);
 
     EasyMock.expect(reservation.getInstances()).andReturn(Collections.singletonList(instance)).atLeastOnce();
@@ -177,12 +179,8 @@ public void testIptoIdLookup()
     Arrays.fill(chunk1, reservation);
     final Reservation[] chunk2 = new Reservation[n - EC2AutoScaler.MAX_AWS_FILTER_VALUES];
     Arrays.fill(chunk2, reservation);
-    EasyMock.expect(describeInstancesResult.getReservations()).andReturn(
-        Lists.newArrayList(chunk1)
-    );
-    EasyMock.expect(describeInstancesResult.getReservations()).andReturn(
-        Lists.newArrayList(chunk2)
-    );
+    EasyMock.expect(describeInstancesResult.getReservations()).andReturn(Arrays.asList(chunk1));
+    EasyMock.expect(describeInstancesResult.getReservations()).andReturn(Arrays.asList(chunk2));
     EasyMock.replay(describeInstancesResult);
 
     EasyMock.expect(reservation.getInstances()).andReturn(Collections.singletonList(instance)).times(n);
@@ -234,12 +232,8 @@ public void testIdToIpLookup()
     Arrays.fill(chunk1, reservation);
     final Reservation[] chunk2 = new Reservation[n - EC2AutoScaler.MAX_AWS_FILTER_VALUES];
     Arrays.fill(chunk2, reservation);
-    EasyMock.expect(describeInstancesResult.getReservations()).andReturn(
-        Lists.newArrayList(chunk1)
-    );
-    EasyMock.expect(describeInstancesResult.getReservations()).andReturn(
-        Lists.newArrayList(chunk2)
-    );
+    EasyMock.expect(describeInstancesResult.getReservations()).andReturn(Arrays.asList(chunk1));
+    EasyMock.expect(describeInstancesResult.getReservations()).andReturn(Arrays.asList(chunk2));
     EasyMock.replay(describeInstancesResult);
 
     EasyMock.expect(reservation.getInstances()).andReturn(Collections.singletonList(instance)).times(n);

processing/src/main/java/io/druid/query/topn/TopNNumericResultBuilder.java

@@ -47,7 +47,6 @@ public class TopNNumericResultBuilder implements TopNResultBuilder
   private final String metricName;
   private final List<PostAggregator> postAggs;
   private final PriorityQueue<DimValHolder> pQueue;
-  private final Comparator<DimValHolder> dimValHolderComparator;
   private final String[] aggFactoryNames;
   private static final Comparator<Comparable> dimValueComparator = new Comparator<Comparable>()
   {
@@ -91,7 +90,8 @@ public TopNNumericResultBuilder(
     this.postAggs = AggregatorUtil.pruneDependentPostAgg(postAggs, this.metricName);
     this.threshold = threshold;
     this.metricComparator = comparator;
-    this.dimValHolderComparator = (d1, d2) -> {
+
+    final Comparator<DimValHolder> dimValHolderComparator = (d1, d2) -> {
       //noinspection unchecked
       int retVal = metricComparator.compare(d1.getTopNMetricVal(), d2.getTopNMetricVal());
 

processing/src/test/java/io/druid/collections/bitmap/BitmapBenchmark.java

@@ -22,7 +22,6 @@
 import com.carrotsearch.junitbenchmarks.BenchmarkOptions;
 import com.carrotsearch.junitbenchmarks.BenchmarkRule;
 import com.carrotsearch.junitbenchmarks.Clock;
-import com.google.common.collect.Lists;
 import io.druid.extendedset.intset.ImmutableConciseSet;
 import org.junit.Assert;
 import org.junit.Rule;
@@ -36,6 +35,7 @@
 import java.io.DataOutputStream;
 import java.io.IOException;
 import java.nio.ByteBuffer;
+import java.util.Arrays;
 import java.util.Locale;
 import java.util.Random;
 
@@ -152,50 +152,50 @@ public void timeOffheapConciseUnion()
   @BenchmarkOptions(warmupRounds = 1, benchmarkRounds = 2)
   public void timeGenericConciseUnion()
   {
-    ImmutableBitmap union = conciseFactory.union(Lists.newArrayList(genericConcise));
+    ImmutableBitmap union = conciseFactory.union(Arrays.asList(genericConcise));
     Assert.assertEquals(unionCount, union.size());
   }
 
   @Test
   @BenchmarkOptions(warmupRounds = 1, benchmarkRounds = 5)
   public void timeGenericConciseIntersection()
   {
-    ImmutableBitmap intersection = conciseFactory.intersection(Lists.newArrayList(genericConcise));
+    ImmutableBitmap intersection = conciseFactory.intersection(Arrays.asList(genericConcise));
     Assert.assertTrue(intersection.size() >= minIntersection);
   }
 
   @Test
   public void timeRoaringUnion()
   {
-    ImmutableRoaringBitmap union = BufferFastAggregation.horizontal_or(Lists.newArrayList(roaring).iterator());
+    ImmutableRoaringBitmap union = BufferFastAggregation.horizontal_or(Arrays.asList(roaring).iterator());
     Assert.assertEquals(unionCount, union.getCardinality());
   }
 
   @Test
   public void timeImmutableRoaringUnion()
   {
-    ImmutableRoaringBitmap union = BufferFastAggregation.horizontal_or(Lists.newArrayList(immutableRoaring).iterator());
+    ImmutableRoaringBitmap union = BufferFastAggregation.horizontal_or(Arrays.asList(immutableRoaring).iterator());
     Assert.assertEquals(unionCount, union.getCardinality());
   }
 
   @Test
   public void timeOffheapRoaringUnion()
   {
-    ImmutableRoaringBitmap union = BufferFastAggregation.horizontal_or(Lists.newArrayList(offheapRoaring).iterator());
+    ImmutableRoaringBitmap union = BufferFastAggregation.horizontal_or(Arrays.asList(offheapRoaring).iterator());
     Assert.assertEquals(unionCount, union.getCardinality());
   }
 
   @Test
   public void timeGenericRoaringUnion()
   {
-    ImmutableBitmap union = roaringFactory.union(Lists.newArrayList(genericRoaring));
+    ImmutableBitmap union = roaringFactory.union(Arrays.asList(genericRoaring));
     Assert.assertEquals(unionCount, union.size());
   }
 
   @Test
   public void timeGenericRoaringIntersection()
   {
-    ImmutableBitmap intersection = roaringFactory.intersection(Lists.newArrayList(genericRoaring));
+    ImmutableBitmap intersection = roaringFactory.intersection(Arrays.asList(genericRoaring));
     Assert.assertTrue(intersection.size() >= minIntersection);
   }
 }

processing/src/test/java/io/druid/query/aggregation/AggregationTestHelper.java

@@ -344,7 +344,7 @@ public Sequence<Row> createIndexAndRunQueryOnSegment(
   {
     File segmentDir = tempFolder.newFolder();
     createIndex(inputDataFile, parserJson, aggregators, segmentDir, minTimestamp, gran, maxRowCount, true);
-    return runQueryOnSegments(Lists.newArrayList(segmentDir), groupByQueryJson);
+    return runQueryOnSegments(Collections.singletonList(segmentDir), groupByQueryJson);
   }
 
   public Sequence<Row> createIndexAndRunQueryOnSegment(

processing/src/test/java/io/druid/query/aggregation/first/StringFirstTimeseriesQueryTest.java

@@ -76,21 +76,21 @@ public void testTopNWithDistinctCountAgg() throws Exception
         new MapBasedInputRow(
             timestamp,
             Lists.newArrayList(visitor_id, client_type),
-            ImmutableMap.<String, Object>of(visitor_id, "0", client_type, "iphone")
+            ImmutableMap.of(visitor_id, "0", client_type, "iphone")
         )
     );
     index.add(
         new MapBasedInputRow(
             timestamp,
             Lists.newArrayList(visitor_id, client_type),
-            ImmutableMap.<String, Object>of(visitor_id, "1", client_type, "iphone")
+            ImmutableMap.of(visitor_id, "1", client_type, "iphone")
         )
     );
     index.add(
         new MapBasedInputRow(
             timestamp1,
             Lists.newArrayList(visitor_id, client_type),
-            ImmutableMap.<String, Object>of(visitor_id, "0", client_type, "android")
+            ImmutableMap.of(visitor_id, "0", client_type, "android")
         )
     );
 
@@ -114,7 +114,7 @@ public void testTopNWithDistinctCountAgg() throws Exception
         new Result<>(
             time,
             new TimeseriesResultValue(
-                ImmutableMap.<String, Object>of("last_client_type", new SerializablePairLongString(timestamp, "iphone"))
+                ImmutableMap.of("last_client_type", new SerializablePairLongString(timestamp, "iphone"))
             )
         )
     );

processing/src/test/java/io/druid/query/aggregation/last/StringLastTimeseriesQueryTest.java

@@ -76,21 +76,21 @@ public void testTopNWithDistinctCountAgg() throws Exception
         new MapBasedInputRow(
             timestamp,
             Lists.newArrayList(visitor_id, client_type),
-            ImmutableMap.<String, Object>of(visitor_id, "0", client_type, "iphone")
+            ImmutableMap.of(visitor_id, "0", client_type, "iphone")
         )
     );
     index.add(
         new MapBasedInputRow(
             timestamp,
             Lists.newArrayList(visitor_id, client_type),
-            ImmutableMap.<String, Object>of(visitor_id, "1", client_type, "iphone")
+            ImmutableMap.of(visitor_id, "1", client_type, "iphone")
         )
     );
     index.add(
         new MapBasedInputRow(
             timestamp1,
             Lists.newArrayList(visitor_id, client_type),
-            ImmutableMap.<String, Object>of(visitor_id, "0", client_type, "android")
+            ImmutableMap.of(visitor_id, "0", client_type, "android")
         )
     );
 
@@ -99,7 +99,7 @@ public void testTopNWithDistinctCountAgg() throws Exception
                                   .granularity(QueryRunnerTestHelper.allGran)
                                   .intervals(QueryRunnerTestHelper.fullOnInterval)
                                   .aggregators(
-                                      Lists.newArrayList(
+                                      Collections.singletonList(
                                           new StringLastAggregatorFactory(
                                               "last_client_type", client_type, 1024
                                           )
@@ -114,7 +114,7 @@ public void testTopNWithDistinctCountAgg() throws Exception
         new Result<>(
             time,
             new TimeseriesResultValue(
-                ImmutableMap.<String, Object>of(
+                ImmutableMap.of(
                     "last_client_type",
                     new SerializablePairLongString(timestamp1, "android")
                 )

processing/src/test/java/io/druid/segment/filter/BoundFilterTest.java

@@ -161,7 +161,7 @@ public void testLexicographicMatchMissingColumn()
       );
       assertFilterMatches(
           new BoundDimFilter("dim3", null, "", false, true, false, null, StringComparators.LEXICOGRAPHIC),
-          ImmutableList.<String>of()
+          ImmutableList.of()
       );
     } else {
       assertFilterMatches(
@@ -174,7 +174,7 @@ public void testLexicographicMatchMissingColumn()
       );
       assertFilterMatches(
           new BoundDimFilter("dim3", null, "", false, true, false, null, StringComparators.LEXICOGRAPHIC),
-          ImmutableList.<String>of("0", "1", "2", "3", "4", "5", "6", "7")
+          ImmutableList.of("0", "1", "2", "3", "4", "5", "6", "7")
       );
     }
     assertFilterMatches(

processing/src/test/java/io/druid/segment/filter/ColumnComparisonFilterTest.java

@@ -123,35 +123,35 @@ public void testMissingColumnNotSpecifiedInDimensionList()
         new ColumnComparisonDimFilter(
             ImmutableList.of(DefaultDimensionSpec.of("dim6"), DefaultDimensionSpec.of("dim7"))
         ),
-        ImmutableList.<String>of("0", "1", "2", "3", "4", "5", "6", "7", "8", "9")
+        ImmutableList.of("0", "1", "2", "3", "4", "5", "6", "7", "8", "9")
     );
     if (NullHandling.replaceWithDefault()) {
       assertFilterMatches(
           new ColumnComparisonDimFilter(
               ImmutableList.of(DefaultDimensionSpec.of("dim1"), DefaultDimensionSpec.of("dim6"))
           ),
-          ImmutableList.<String>of("0")
+          ImmutableList.of("0")
       );
 
       assertFilterMatches(
           new ColumnComparisonDimFilter(
               ImmutableList.of(DefaultDimensionSpec.of("dim2"), DefaultDimensionSpec.of("dim6"))
           ),
-          ImmutableList.<String>of("1", "2", "6", "7", "8")
+          ImmutableList.of("1", "2", "6", "7", "8")
       );
     } else {
       assertFilterMatches(
           new ColumnComparisonDimFilter(
               ImmutableList.of(DefaultDimensionSpec.of("dim1"), DefaultDimensionSpec.of("dim6"))
           ),
-          ImmutableList.<String>of()
+          ImmutableList.of()
       );
 
       assertFilterMatches(
           new ColumnComparisonDimFilter(
               ImmutableList.of(DefaultDimensionSpec.of("dim2"), DefaultDimensionSpec.of("dim6"))
           ),
-          ImmutableList.<String>of("1", "6", "7", "8")
+          ImmutableList.of("1", "6", "7", "8")
       );
     }
   }

processing/src/test/java/io/druid/segment/filter/SearchQueryFilterTest.java

@@ -192,7 +192,7 @@ public void testSearchQueryWithExtractionFn()
 
     assertFilterMatches(
         new SearchQueryDimFilter("dim1", specForValue("ab"), changeNullFn),
-        ImmutableList.<String>of("4", "5")
+        ImmutableList.of("4", "5")
     );
     assertFilterMatches(new SearchQueryDimFilter("dim1", specForValue("ab"), changeNullFn), ImmutableList.of("4", "5"));
 

server/src/main/java/io/druid/server/coordinator/helper/DruidCoordinatorBalancer.java

@@ -131,6 +131,7 @@ private void balanceTier(
     final int maxToLoad = params.getCoordinatorDynamicConfig().getMaxSegmentsInNodeLoadingQueue();
     int moved = 0, unmoved = 0;
 
+    //noinspection ForLoopThatDoesntUseLoopVariable
     for (int iter = 0; (moved + unmoved) < maxSegmentsToMove; ++iter) {
       final BalancerSegmentHolder segmentToMoveHolder = strategy.pickSegmentToMove(toMoveFrom);
 

server/src/test/java/io/druid/client/selector/TierSelectorStrategyTest.java

@@ -33,6 +33,7 @@
 import org.junit.Assert;
 import org.junit.Test;
 
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
@@ -131,7 +132,7 @@ private void testTierSelectorStrategy(
         tierSelectorStrategy
     );
 
-    List<QueryableDruidServer> servers = Lists.newArrayList(expectedSelection);
+    List<QueryableDruidServer> servers = new ArrayList<>(Arrays.asList(expectedSelection));
 
     List<DruidServerMetadata> expectedCandidates = Lists.newArrayList();
     for (QueryableDruidServer server : servers) {