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Posted to commits@hbase.apache.org by st...@apache.org on 2017/01/21 06:58:35 UTC

[3/3] hbase git commit: HBASE-10699 Set capacity on ArrayList where possible and use isEmpty instead of size() == 0

HBASE-10699 Set capacity on ArrayList where possible and use isEmpty instead of size() == 0

Signed-off-by: Michael Stack <st...@apache.org>


Project: http://git-wip-us.apache.org/repos/asf/hbase/repo
Commit: http://git-wip-us.apache.org/repos/asf/hbase/commit/55a1aa1e
Tree: http://git-wip-us.apache.org/repos/asf/hbase/tree/55a1aa1e
Diff: http://git-wip-us.apache.org/repos/asf/hbase/diff/55a1aa1e

Branch: refs/heads/master
Commit: 55a1aa1e73b5bda877facbcfce6ff7d52b35ecec
Parents: c74cf12
Author: Jan Hentschel <ja...@ultratendency.com>
Authored: Sat Jan 21 00:38:03 2017 +0100
Committer: Michael Stack <st...@apache.org>
Committed: Fri Jan 20 22:58:20 2017 -0800

----------------------------------------------------------------------
 .../classification/tools/StabilityOptions.java  |   2 +-
 .../apache/hadoop/hbase/HTableDescriptor.java   |   2 +-
 .../apache/hadoop/hbase/MetaTableAccessor.java  |   4 +-
 .../org/apache/hadoop/hbase/client/Append.java  |   2 +-
 .../hadoop/hbase/client/AsyncProcess.java       |   4 +-
 .../hbase/client/AsyncRequestFutureImpl.java    |   2 +-
 .../org/apache/hadoop/hbase/client/Delete.java  |  10 +-
 .../org/apache/hadoop/hbase/client/Get.java     |   4 +-
 .../apache/hadoop/hbase/client/HBaseAdmin.java  |   4 +-
 .../apache/hadoop/hbase/client/Mutation.java    |   4 +-
 .../org/apache/hadoop/hbase/client/Scan.java    |   2 +-
 .../replication/ReplicationSerDeHelper.java     |   7 +-
 .../hadoop/hbase/filter/CompareFilter.java      |   2 +-
 .../hadoop/hbase/filter/TimestampsFilter.java   |   2 +-
 .../replication/ReplicationPeersZKImpl.java     |   2 +-
 .../replication/ReplicationQueuesZKImpl.java    |   8 +-
 .../hbase/shaded/protobuf/ProtobufUtil.java     |   4 +-
 .../shaded/protobuf/ResponseConverter.java      |   2 +-
 .../org/apache/hadoop/hbase/util/Writables.java |   2 +-
 .../hbase/zookeeper/MetaTableLocator.java       |   2 +-
 .../hadoop/hbase/client/TestAsyncProcess.java   |  24 ++---
 .../hadoop/hbase/filter/TestKeyOnlyFilter.java  |   2 +-
 .../hbase/ipc/TestHBaseRpcControllerImpl.java   |   3 +-
 .../org/apache/hadoop/hbase/ChoreService.java   |   2 +-
 .../java/org/apache/hadoop/hbase/KeyValue.java  |   2 +-
 .../hadoop/hbase/util/AbstractHBaseTool.java    |   2 +-
 .../apache/hadoop/hbase/ResourceChecker.java    |   4 +-
 .../hbase/util/ClassLoaderTestHelper.java       |   4 +-
 .../org/apache/hadoop/hbase/util/TestBytes.java |   4 +-
 .../client/coprocessor/AggregationClient.java   |   4 +-
 .../coprocessor/TestRowProcessorEndpoint.java   |   6 +-
 .../SecureBulkLoadEndpointClient.java           |   2 +-
 .../apache/hadoop/hbase/thrift/DemoClient.java  |  14 +--
 .../hadoop/hbase/thrift/HttpDoAsClient.java     |   2 +-
 .../apache/hadoop/hbase/thrift2/DemoClient.java |   2 +-
 .../metrics2/util/MetricSampleQuantiles.java    |   4 +-
 .../hbase/IntegrationTestDDLMasterFailover.java |   2 +-
 .../hadoop/hbase/IntegrationTestIngest.java     |   2 +-
 ...tegrationTestIngestWithVisibilityLabels.java |  14 +--
 .../hbase/ipc/IntegrationTestRpcClient.java     |   2 +-
 .../test/IntegrationTestBigLinkedList.java      |   2 +-
 .../row/data/TestRowDataExerciseFInts.java      |   2 +-
 .../row/data/TestRowDataTrivialWithTags.java    |   2 +-
 .../prefixtree/row/data/TestRowDataUrls.java    |   2 +-
 .../timestamp/data/TestTimestampDataBasic.java  |   4 +-
 .../data/TestTimestampDataNumbers.java          |   4 +-
 .../data/TestTimestampDataRepeats.java          |   2 +-
 .../store/wal/ProcedureWALPrettyPrinter.java    |   2 +-
 .../hadoop/hbase/rest/MultiRowResource.java     |   2 +-
 .../hadoop/hbase/rest/client/RemoteHTable.java  |   2 +-
 .../rest/model/NamespacesInstanceModel.java     |   2 +-
 .../hbase/rest/model/NamespacesModel.java       |   2 +-
 .../hadoop/hbase/rest/model/ScannerModel.java   |   2 +-
 .../hadoop/hbase/rest/TestMultiRowResource.java |   2 +-
 .../hbase/rest/TestScannersWithFilters.java     |   2 +-
 .../hbase/rest/TestScannersWithLabels.java      |   2 +-
 .../hadoop/hbase/rest/TestSchemaResource.java   |   2 +-
 .../hbase/rest/client/TestRemoteTable.java      |  14 +--
 .../hbase/rsgroup/RSGroupInfoManagerImpl.java   |   2 +-
 .../hadoop/hbase/rsgroup/TestRSGroupsBase.java  |   4 +-
 .../hadoop/hbase/backup/HFileArchiver.java      |   4 +-
 .../hbase/errorhandling/ForeignException.java   |   2 +-
 .../favored/FavoredNodeAssignmentHelper.java    |   4 +-
 .../hadoop/hbase/favored/FavoredNodesPlan.java  |   2 +-
 .../apache/hadoop/hbase/http/HttpServer.java    |   6 +-
 .../hbase/mapreduce/TableMapReduceUtil.java     |   2 +-
 .../hadoop/hbase/master/CatalogJanitor.java     |   2 +-
 .../org/apache/hadoop/hbase/master/HMaster.java |   2 +-
 .../hadoop/hbase/master/RegionStates.java       |   2 +-
 .../hadoop/hbase/master/ServerManager.java      |   2 +-
 .../hadoop/hbase/master/SplitLogManager.java    |   2 +-
 .../master/balancer/SimpleLoadBalancer.java     |   2 +-
 .../hbase/regionserver/CompactionTool.java      |   2 +-
 .../hadoop/hbase/regionserver/HRegion.java      |   2 +-
 .../hadoop/hbase/regionserver/HStore.java       |   2 +-
 .../compactions/ExploringCompactionPolicy.java  |   2 +-
 .../compactions/StripeCompactionPolicy.java     |   2 +-
 .../querymatcher/LegacyScanQueryMatcher.java    |   2 +-
 .../querymatcher/UserScanQueryMatcher.java      |   2 +-
 .../regionserver/wal/WALEditsReplaySink.java    |   2 +-
 .../replication/master/TableCFsUpdater.java     |   2 +-
 .../regionserver/ReplicationSink.java           |   6 +-
 .../regionserver/ReplicationSource.java         |   4 +-
 .../regionserver/ReplicationSourceManager.java  |   2 +-
 .../DefaultVisibilityLabelServiceImpl.java      |   2 +-
 .../hbase/snapshot/RestoreSnapshotHelper.java   |   8 +-
 .../hadoop/hbase/snapshot/SnapshotInfo.java     |   2 +-
 .../hadoop/hbase/snapshot/SnapshotManifest.java |   2 +-
 .../hbase/snapshot/SnapshotReferenceUtil.java   |   6 +-
 .../org/apache/hadoop/hbase/tool/Canary.java    |   2 +-
 .../org/apache/hadoop/hbase/util/HBaseFsck.java |  12 +--
 .../org/apache/hadoop/hbase/util/IdLock.java    |   2 +-
 .../apache/hadoop/hbase/util/RegionMover.java   |   8 +-
 .../hbase/util/hbck/HFileCorruptionChecker.java |  12 +--
 .../hadoop/hbase/wal/AbstractFSWALProvider.java |   2 +-
 .../hadoop/hbase/wal/DisabledWALProvider.java   |   2 +-
 .../org/apache/hadoop/hbase/wal/WALKey.java     |   2 +-
 .../hadoop/hbase/wal/WALPrettyPrinter.java      |   4 +-
 .../hbase/zookeeper/MiniZooKeeperCluster.java   |   2 +-
 .../hbase/TestPartialResultsFromClientSide.java |   2 +-
 .../hadoop/hbase/client/TestFromClientSide.java |   2 +-
 .../client/TestScannersFromClientSide.java      |   2 +-
 .../master/TestDistributedLogSplitting.java     |  16 +--
 .../hbase/master/TestRegionPlacement.java       |  10 +-
 .../hbase/regionserver/TestColumnSeeking.java   |   4 +-
 .../TestDefaultCompactSelection.java            |   2 +-
 .../TestEndToEndSplitTransaction.java           |   2 +-
 .../hadoop/hbase/regionserver/TestHRegion.java  |   2 +-
 .../TestSplitTransactionOnCluster.java          |   2 +-
 .../TestCompactedHFilesDischarger.java          |   8 +-
 .../compactions/TestStripeCompactionPolicy.java |   4 +-
 .../compactions/TestStripeCompactor.java        |   2 +-
 .../querymatcher/TestExplicitColumnTracker.java |  10 +-
 .../TestScanWildcardColumnTracker.java          |  14 +--
 .../querymatcher/TestUserScanQueryMatcher.java  |  12 +--
 .../regionserver/wal/AbstractTestFSWAL.java     |   2 +-
 .../hbase/regionserver/wal/TestLogRolling.java  |   2 +-
 .../wal/TestWALActionsListener.java             |   2 +-
 .../replication/TestMasterReplication.java      |   4 +-
 .../replication/TestMultiSlaveReplication.java  |   2 +-
 .../replication/TestNamespaceReplication.java   |   2 +-
 .../replication/TestPerTableCFReplication.java  |   2 +-
 ...estReplicationChangingPeerRegionservers.java |   2 +-
 .../TestReplicationDisableInactivePeer.java     |   2 +-
 .../replication/TestReplicationSmallTests.java  |  12 +--
 .../replication/TestReplicationStateBasic.java  |   2 +-
 .../replication/TestReplicationWithTags.java    |   4 +-
 .../replication/TestSerialReplication.java      |   2 +-
 .../regionserver/TestGlobalThrottler.java       |   2 +-
 .../TestReplicationSourceManager.java           |   2 +-
 .../TestReplicationWALReaderManager.java        |   2 +-
 .../security/access/TestAccessController.java   |   6 +-
 .../access/TestZKPermissionsWatcher.java        |   4 +-
 .../visibility/TestVisibilityLabels.java        |   8 +-
 ...sibilityLabelsOpWithDifferentUsersNoACL.java |   2 +-
 .../TestVisibilityLabelsReplication.java        |   4 +-
 .../visibility/TestVisibilityLabelsWithACL.java |   4 +-
 .../TestVisibilityLabelsWithDeletes.java        |  10 +-
 .../TestVisibilityLablesWithGroups.java         |   4 +-
 .../TestWithDisabledAuthorization.java          |   4 +-
 .../snapshot/TestExportSnapshotHelpers.java     |   2 +-
 .../hadoop/hbase/util/BaseTestHBaseFsck.java    |   6 +-
 .../hbase/util/HFileArchiveTestingUtil.java     |   2 +-
 .../hadoop/hbase/util/TestHBaseFsckOneRS.java   |   2 +-
 .../hbase/util/TestRegionSizeCalculator.java    |   2 +-
 .../hbase/util/TestRegionSplitCalculator.java   |   2 +-
 .../hadoop/hbase/util/TestRegionSplitter.java   |   6 +-
 .../apache/hadoop/hbase/wal/IOTestProvider.java |   2 +-
 .../hbase/zookeeper/TestZooKeeperACL.java       |   2 +-
 .../hadoop/hbase/client/AbstractTestShell.java  |   2 +-
 .../hadoop/hbase/client/TestShellNoCluster.java |   2 +-
 .../hbase/client/rsgroup/TestShellRSGroups.java |   2 +-
 .../JavaHBaseBulkDeleteExample.java             |   2 +-
 .../hbasecontext/JavaHBaseBulkGetExample.java   |   2 +-
 .../hbasecontext/JavaHBaseBulkPutExample.java   |   2 +-
 .../hbasecontext/JavaHBaseMapGetPutExample.java |   2 +-
 .../spark/datasources/HBaseTableScanRDD.scala   |   2 +-
 .../hbase/spark/TestJavaHBaseContext.java       |  10 +-
 .../hadoop/hbase/thrift/ThriftServerRunner.java |   4 +-
 .../hadoop/hbase/thrift/ThriftUtilities.java    |   2 +-
 .../hadoop/hbase/thrift2/ThriftUtilities.java   |   6 +-
 .../hbase/thrift/TestThriftHttpServer.java      |   2 +-
 .../hadoop/hbase/thrift/TestThriftServer.java   |  24 ++---
 .../thrift2/TestThriftHBaseServiceHandler.java  | 100 +++++++++----------
 ...TestThriftHBaseServiceHandlerWithLabels.java |  34 +++----
 165 files changed, 389 insertions(+), 381 deletions(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-annotations/src/main/java/org/apache/hadoop/hbase/classification/tools/StabilityOptions.java
----------------------------------------------------------------------
diff --git a/hbase-annotations/src/main/java/org/apache/hadoop/hbase/classification/tools/StabilityOptions.java b/hbase-annotations/src/main/java/org/apache/hadoop/hbase/classification/tools/StabilityOptions.java
index 0911fd5..6cb03a5 100644
--- a/hbase-annotations/src/main/java/org/apache/hadoop/hbase/classification/tools/StabilityOptions.java
+++ b/hbase-annotations/src/main/java/org/apache/hadoop/hbase/classification/tools/StabilityOptions.java
@@ -53,7 +53,7 @@ final class StabilityOptions {
   }
 
   public static String[][] filterOptions(String[][] options) {
-    List<String[]> optionsList = new ArrayList<String[]>();
+    List<String[]> optionsList = new ArrayList<String[]>(options.length);
     for (int i = 0; i < options.length; i++) {
       if (!options[i][0].equalsIgnoreCase(UNSTABLE_OPTION)
           && !options[i][0].equalsIgnoreCase(EVOLVING_OPTION)

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/main/java/org/apache/hadoop/hbase/HTableDescriptor.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/HTableDescriptor.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/HTableDescriptor.java
index be8e858..60b85fe 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/HTableDescriptor.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/HTableDescriptor.java
@@ -1387,7 +1387,7 @@ public class HTableDescriptor implements Comparable<HTableDescriptor> {
    * @return The list of co-processors classNames
    */
   public List<String> getCoprocessors() {
-    List<String> result = new ArrayList<String>();
+    List<String> result = new ArrayList<String>(this.values.entrySet().size());
     Matcher keyMatcher;
     for (Map.Entry<Bytes, Bytes> e : this.values.entrySet()) {
       keyMatcher = HConstants.CP_HTD_ATTR_KEY_PATTERN.matcher(Bytes.toString(e.getKey().get()));

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/main/java/org/apache/hadoop/hbase/MetaTableAccessor.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/MetaTableAccessor.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/MetaTableAccessor.java
index 4963355..1cc7963 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/MetaTableAccessor.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/MetaTableAccessor.java
@@ -1897,7 +1897,7 @@ public class MetaTableAccessor {
    */
   public static void updateReplicationPositions(Connection connection, String peerId,
       Map<String, Long> positions) throws IOException {
-    List<Put> puts = new ArrayList<>();
+    List<Put> puts = new ArrayList<>(positions.entrySet().size());
     for (Map.Entry<String, Long> entry : positions.entrySet()) {
       long value = Math.abs(entry.getValue());
       Put put = new Put(Bytes.toBytes(entry.getKey()));
@@ -2169,7 +2169,7 @@ public class MetaTableAccessor {
       Result result;
       while ((result = scanner.next()) != null) {
         String key = Bytes.toString(result.getRow());
-        List<Long> list = new ArrayList<>();
+        List<Long> list = new ArrayList<>(result.rawCells().length);
         for (Cell cell : result.rawCells()) {
           list.add(Bytes.toLong(cell.getQualifierArray(), cell.getQualifierOffset(),
               cell.getQualifierLength()));

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Append.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Append.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Append.java
index 45f1e46..fd2df93 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Append.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Append.java
@@ -123,7 +123,7 @@ public class Append extends Mutation {
     byte [] family = CellUtil.cloneFamily(cell);
     List<Cell> list = this.familyMap.get(family);
     if (list == null) {
-      list  = new ArrayList<Cell>();
+      list  = new ArrayList<Cell>(1);
     }
     // find where the new entry should be placed in the List
     list.add(cell);

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncProcess.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncProcess.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncProcess.java
index d1583f5..269d316 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncProcess.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncProcess.java
@@ -287,8 +287,8 @@ class AsyncProcess {
           }
           loc = locs.getDefaultRegionLocation();
         } catch (IOException ex) {
-          locationErrors = new ArrayList<Exception>();
-          locationErrorRows = new ArrayList<Integer>();
+          locationErrors = new ArrayList<Exception>(1);
+          locationErrorRows = new ArrayList<Integer>(1);
           LOG.error("Failed to get region location ", ex);
           // This action failed before creating ars. Retain it, but do not add to submit list.
           // We will then add it to ars in an already-failed state.

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncRequestFutureImpl.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncRequestFutureImpl.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncRequestFutureImpl.java
index b0a2798..c3caff8 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncRequestFutureImpl.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncRequestFutureImpl.java
@@ -463,7 +463,7 @@ class AsyncRequestFutureImpl<CResult> implements AsyncRequestFuture {
       if (loc == null || loc.getServerName() == null) {
         if (isReplica) {
           if (unknownReplicaActions == null) {
-            unknownReplicaActions = new ArrayList<Action>();
+            unknownReplicaActions = new ArrayList<Action>(1);
           }
           unknownReplicaActions.add(action);
         } else {

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Delete.java
----------------------------------------------------------------------
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 d61a197..9c6c1a5 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
@@ -172,7 +172,7 @@ public class Delete extends Mutation implements Comparable<Row> {
     byte [] family = CellUtil.cloneFamily(kv);
     List<Cell> list = familyMap.get(family);
     if (list == null) {
-      list = new ArrayList<Cell>();
+      list = new ArrayList<Cell>(1);
     }
     list.add(kv);
     familyMap.put(family, list);
@@ -209,7 +209,7 @@ public class Delete extends Mutation implements Comparable<Row> {
     }
     List<Cell> list = familyMap.get(family);
     if(list == null) {
-      list = new ArrayList<Cell>();
+      list = new ArrayList<Cell>(1);
     } else if(!list.isEmpty()) {
       list.clear();
     }
@@ -229,7 +229,7 @@ public class Delete extends Mutation implements Comparable<Row> {
   public Delete addFamilyVersion(final byte [] family, final long timestamp) {
     List<Cell> list = familyMap.get(family);
     if(list == null) {
-      list = new ArrayList<Cell>();
+      list = new ArrayList<Cell>(1);
     }
     list.add(new KeyValue(row, family, null, timestamp,
           KeyValue.Type.DeleteFamilyVersion));
@@ -262,7 +262,7 @@ public class Delete extends Mutation implements Comparable<Row> {
     }
     List<Cell> list = familyMap.get(family);
     if (list == null) {
-      list = new ArrayList<Cell>();
+      list = new ArrayList<Cell>(1);
     }
     list.add(new KeyValue(this.row, family, qualifier, timestamp,
         KeyValue.Type.DeleteColumn));
@@ -297,7 +297,7 @@ public class Delete extends Mutation implements Comparable<Row> {
     }
     List<Cell> list = familyMap.get(family);
     if(list == null) {
-      list = new ArrayList<Cell>();
+      list = new ArrayList<Cell>(1);
     }
     KeyValue kv = new KeyValue(this.row, family, qualifier, timestamp, KeyValue.Type.Delete);
     list.add(kv);

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Get.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Get.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Get.java
index 4dc656f..947b54a 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Get.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Get.java
@@ -400,7 +400,7 @@ public class Get extends Query
   @Override
   public Map<String, Object> getFingerprint() {
     Map<String, Object> map = new HashMap<String, Object>();
-    List<String> families = new ArrayList<String>();
+    List<String> families = new ArrayList<String>(this.familyMap.entrySet().size());
     map.put("families", families);
     for (Map.Entry<byte [], NavigableSet<byte[]>> entry :
       this.familyMap.entrySet()) {
@@ -428,7 +428,7 @@ public class Get extends Query
     map.put("row", Bytes.toStringBinary(this.row));
     map.put("maxVersions", this.maxVersions);
     map.put("cacheBlocks", this.cacheBlocks);
-    List<Long> timeRange = new ArrayList<Long>();
+    List<Long> timeRange = new ArrayList<Long>(2);
     timeRange.add(this.tr.getMin());
     timeRange.add(this.tr.getMax());
     map.put("timeRange", timeRange);

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/main/java/org/apache/hadoop/hbase/client/HBaseAdmin.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/HBaseAdmin.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/HBaseAdmin.java
index db9cea5..9befc48 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/HBaseAdmin.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/HBaseAdmin.java
@@ -3865,7 +3865,7 @@ public class HBaseAdmin implements Admin {
 
   @Override
   public void drainRegionServers(List<ServerName> servers) throws IOException {
-    final List<HBaseProtos.ServerName> pbServers = new ArrayList<HBaseProtos.ServerName>();
+    final List<HBaseProtos.ServerName> pbServers = new ArrayList<HBaseProtos.ServerName>(servers.size());
     for (ServerName server : servers) {
       // Parse to ServerName to do simple validation.
       ServerName.parseServerName(server.toString());
@@ -3902,7 +3902,7 @@ public class HBaseAdmin implements Admin {
 
   @Override
   public void removeDrainFromRegionServers(List<ServerName> servers) throws IOException {
-    final List<HBaseProtos.ServerName> pbServers = new ArrayList<HBaseProtos.ServerName>();
+    final List<HBaseProtos.ServerName> pbServers = new ArrayList<HBaseProtos.ServerName>(servers.size());
     for (ServerName server : servers) {
       pbServers.add(ProtobufUtil.toServerName(server));
     }

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Mutation.java
----------------------------------------------------------------------
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 42c159e..53631d9 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
@@ -159,7 +159,7 @@ public abstract class Mutation extends OperationWithAttributes implements Row, C
   @Override
   public Map<String, Object> getFingerprint() {
     Map<String, Object> map = new HashMap<String, Object>();
-    List<String> families = new ArrayList<String>();
+    List<String> families = new ArrayList<String>(this.familyMap.entrySet().size());
     // ideally, we would also include table information, but that information
     // is not stored in each Operation instance.
     map.put("families", families);
@@ -227,7 +227,7 @@ public abstract class Mutation extends OperationWithAttributes implements Row, C
     stringMap.put("vlen", c.getValueLength());
     List<Tag> tags = CellUtil.getTags(c);
     if (tags != null) {
-      List<String> tagsString = new ArrayList<String>();
+      List<String> tagsString = new ArrayList<String>(tags.size());
       for (Tag t : tags) {
         tagsString.add((t.getType()) + ":" + Bytes.toStringBinary(TagUtil.cloneValue(t)));
       }

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Scan.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Scan.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Scan.java
index a2d9037..8d53b9a 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Scan.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Scan.java
@@ -908,7 +908,7 @@ public class Scan extends Query {
     map.put("maxResultSize", this.maxResultSize);
     map.put("cacheBlocks", this.cacheBlocks);
     map.put("loadColumnFamiliesOnDemand", this.loadColumnFamiliesOnDemand);
-    List<Long> timeRange = new ArrayList<Long>();
+    List<Long> timeRange = new ArrayList<Long>(2);
     timeRange.add(this.tr.getMin());
     timeRange.add(this.tr.getMax());
     map.put("timeRange", timeRange);

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/main/java/org/apache/hadoop/hbase/client/replication/ReplicationSerDeHelper.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/replication/ReplicationSerDeHelper.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/replication/ReplicationSerDeHelper.java
index 93eea17..2965219 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/replication/ReplicationSerDeHelper.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/replication/ReplicationSerDeHelper.java
@@ -68,7 +68,7 @@ public final class ReplicationSerDeHelper {
     if (tableCfs == null) {
       return null;
     }
-    List<ReplicationProtos.TableCF> tableCFList = new ArrayList<>();
+    List<ReplicationProtos.TableCF> tableCFList = new ArrayList<>(tableCfs.entrySet().size());
     ReplicationProtos.TableCF.Builder tableCFBuilder =  ReplicationProtos.TableCF.newBuilder();
     for (Map.Entry<TableName, ? extends Collection<String>> entry : tableCfs.entrySet()) {
       tableCFBuilder.clear();
@@ -100,10 +100,11 @@ public final class ReplicationSerDeHelper {
     if (tableCFsConfig == null || tableCFsConfig.trim().length() == 0) {
       return null;
     }
-    List<ReplicationProtos.TableCF> tableCFList = new ArrayList<>();
-    ReplicationProtos.TableCF.Builder tableCFBuilder = ReplicationProtos.TableCF.newBuilder();
 
+    ReplicationProtos.TableCF.Builder tableCFBuilder = ReplicationProtos.TableCF.newBuilder();
     String[] tables = tableCFsConfig.split(";");
+    List<ReplicationProtos.TableCF> tableCFList = new ArrayList<>(tables.length);
+
     for (String tab : tables) {
       // 1 ignore empty table config
       tab = tab.trim();

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/main/java/org/apache/hadoop/hbase/filter/CompareFilter.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/filter/CompareFilter.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/filter/CompareFilter.java
index 6b64e0d..e74797d 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/filter/CompareFilter.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/filter/CompareFilter.java
@@ -177,7 +177,7 @@ public abstract class CompareFilter extends FilterBase {
                                             " can only be used with EQUAL and NOT_EQUAL");
       }
     }
-    ArrayList<Object> arguments = new ArrayList<Object>();
+    ArrayList<Object> arguments = new ArrayList<Object>(2);
     arguments.add(compareOp);
     arguments.add(comparator);
     return arguments;

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/main/java/org/apache/hadoop/hbase/filter/TimestampsFilter.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/filter/TimestampsFilter.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/filter/TimestampsFilter.java
index 2f10d9a..921b7b4 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/filter/TimestampsFilter.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/filter/TimestampsFilter.java
@@ -157,7 +157,7 @@ public class TimestampsFilter extends FilterBase {
   }
 
   public static Filter createFilterFromArguments(ArrayList<byte []> filterArguments) {
-    ArrayList<Long> timestamps = new ArrayList<Long>();
+    ArrayList<Long> timestamps = new ArrayList<Long>(filterArguments.size());
     for (int i = 0; i<filterArguments.size(); i++) {
       long timestamp = ParseFilter.convertByteArrayToLong(filterArguments.get(i));
       timestamps.add(timestamp);

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/main/java/org/apache/hadoop/hbase/replication/ReplicationPeersZKImpl.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/replication/ReplicationPeersZKImpl.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/replication/ReplicationPeersZKImpl.java
index a4b09c3..cf5be83 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/replication/ReplicationPeersZKImpl.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/replication/ReplicationPeersZKImpl.java
@@ -128,7 +128,7 @@ public class ReplicationPeersZKImpl extends ReplicationStateZKBase implements Re
 
       ZKUtil.createWithParents(this.zookeeper, this.peersZNode);
 
-      List<ZKUtilOp> listOfOps = new ArrayList<ZKUtil.ZKUtilOp>();
+      List<ZKUtilOp> listOfOps = new ArrayList<ZKUtil.ZKUtilOp>(2);
       ZKUtilOp op1 = ZKUtilOp.createAndFailSilent(getPeerNode(id),
         ReplicationSerDeHelper.toByteArray(peerConfig));
       // b/w PeerWatcher and ReplicationZookeeper#add method to create the

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/main/java/org/apache/hadoop/hbase/replication/ReplicationQueuesZKImpl.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/replication/ReplicationQueuesZKImpl.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/replication/ReplicationQueuesZKImpl.java
index 1de1315..484084e 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/replication/ReplicationQueuesZKImpl.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/replication/ReplicationQueuesZKImpl.java
@@ -327,8 +327,10 @@ public class ReplicationQueuesZKImpl extends ReplicationStateZKBase implements R
     if (debugEnabled) {
       LOG.debug("Adding hfile references " + pairs + " in queue " + peerZnode);
     }
-    List<ZKUtilOp> listOfOps = new ArrayList<ZKUtil.ZKUtilOp>();
+
     int size = pairs.size();
+    List<ZKUtilOp> listOfOps = new ArrayList<ZKUtil.ZKUtilOp>(size);
+
     for (int i = 0; i < size; i++) {
       listOfOps.add(ZKUtilOp.createAndFailSilent(
         ZKUtil.joinZNode(peerZnode, pairs.get(i).getSecond().getName()),
@@ -352,8 +354,10 @@ public class ReplicationQueuesZKImpl extends ReplicationStateZKBase implements R
     if (debugEnabled) {
       LOG.debug("Removing hfile references " + files + " from queue " + peerZnode);
     }
-    List<ZKUtilOp> listOfOps = new ArrayList<ZKUtil.ZKUtilOp>();
+
     int size = files.size();
+    List<ZKUtilOp> listOfOps = new ArrayList<ZKUtil.ZKUtilOp>(size);
+
     for (int i = 0; i < size; i++) {
       listOfOps.add(ZKUtilOp.deleteNodeFailSilent(ZKUtil.joinZNode(peerZnode, files.get(i))));
     }

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/main/java/org/apache/hadoop/hbase/shaded/protobuf/ProtobufUtil.java
----------------------------------------------------------------------
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 d862d5f..7764f65 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
@@ -1875,7 +1875,7 @@ public final class ProtobufUtil {
    */
   static List<HRegionInfo> getRegionInfos(final GetOnlineRegionResponse proto) {
     if (proto == null) return null;
-    List<HRegionInfo> regionInfos = new ArrayList<HRegionInfo>();
+    List<HRegionInfo> regionInfos = new ArrayList<HRegionInfo>(proto.getRegionInfoList().size());
     for (RegionInfo regionInfo: proto.getRegionInfoList()) {
       regionInfos.add(HRegionInfo.convert(regionInfo));
     }
@@ -2691,7 +2691,7 @@ public final class ProtobufUtil {
 
   public static List<ReplicationLoadSource> toReplicationLoadSourceList(
       List<ClusterStatusProtos.ReplicationLoadSource> clsList) {
-    ArrayList<ReplicationLoadSource> rlsList = new ArrayList<ReplicationLoadSource>();
+    ArrayList<ReplicationLoadSource> rlsList = new ArrayList<ReplicationLoadSource>(clsList.size());
     for (ClusterStatusProtos.ReplicationLoadSource cls : clsList) {
       rlsList.add(toReplicationLoadSource(cls));
     }

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/main/java/org/apache/hadoop/hbase/shaded/protobuf/ResponseConverter.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/shaded/protobuf/ResponseConverter.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/shaded/protobuf/ResponseConverter.java
index 760f630..a83667d 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/shaded/protobuf/ResponseConverter.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/shaded/protobuf/ResponseConverter.java
@@ -232,7 +232,7 @@ public final class ResponseConverter {
   public static List<RegionOpeningState> getRegionOpeningStateList(
       final OpenRegionResponse proto) {
     if (proto == null) return null;
-    List<RegionOpeningState> regionOpeningStates = new ArrayList<RegionOpeningState>();
+    List<RegionOpeningState> regionOpeningStates = new ArrayList<RegionOpeningState>(proto.getOpeningStateCount());
     for (int i = 0; i < proto.getOpeningStateCount(); i++) {
       regionOpeningStates.add(RegionOpeningState.valueOf(
           proto.getOpeningState(i).name()));

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/main/java/org/apache/hadoop/hbase/util/Writables.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/util/Writables.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/util/Writables.java
index e04d789..940d523 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/util/Writables.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/util/Writables.java
@@ -68,7 +68,7 @@ public class Writables {
    * @throws IOException e
    */
   public static byte [] getBytes(final Writable... ws) throws IOException {
-    List<byte []> bytes = new ArrayList<byte []>();
+    List<byte []> bytes = new ArrayList<byte []>(ws.length);
     int size = 0;
     for (Writable w: ws) {
       byte [] b = getBytes(w);

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/main/java/org/apache/hadoop/hbase/zookeeper/MetaTableLocator.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/zookeeper/MetaTableLocator.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/zookeeper/MetaTableLocator.java
index c18811e..e8431a2 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/zookeeper/MetaTableLocator.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/zookeeper/MetaTableLocator.java
@@ -106,7 +106,7 @@ public class MetaTableLocator {
   public List<Pair<HRegionInfo, ServerName>> getMetaRegionsAndLocations(ZooKeeperWatcher zkw,
       int replicaId) {
     ServerName serverName = getMetaRegionLocation(zkw, replicaId);
-    List<Pair<HRegionInfo, ServerName>> list = new ArrayList<Pair<HRegionInfo, ServerName>>();
+    List<Pair<HRegionInfo, ServerName>> list = new ArrayList<Pair<HRegionInfo, ServerName>>(1);
     list.add(new Pair<HRegionInfo, ServerName>(RegionReplicaUtil.getRegionInfoForReplica(
         HRegionInfo.FIRST_META_REGIONINFO, replicaId), serverName));
     return list;

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestAsyncProcess.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestAsyncProcess.java b/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestAsyncProcess.java
index ed7202a..9a09aeb 100644
--- a/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestAsyncProcess.java
+++ b/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestAsyncProcess.java
@@ -682,7 +682,7 @@ public class TestAsyncProcess {
     ClusterConnection hc = createHConnection();
     MyAsyncProcess ap = new MyAsyncProcess(hc, CONF);
 
-    List<Put> puts = new ArrayList<Put>();
+    List<Put> puts = new ArrayList<Put>(1);
     puts.add(createPut(1, true));
 
     ap.submit(null, DUMMY_TABLE, puts, false, null, false);
@@ -701,7 +701,7 @@ public class TestAsyncProcess {
     };
     MyAsyncProcess ap = new MyAsyncProcess(hc, CONF);
 
-    List<Put> puts = new ArrayList<Put>();
+    List<Put> puts = new ArrayList<Put>(1);
     puts.add(createPut(1, true));
 
     final AsyncRequestFuture ars = ap.submit(null, DUMMY_TABLE, puts, false, cb, false);
@@ -718,7 +718,7 @@ public class TestAsyncProcess {
       SimpleRequestController.class.getName());
     MyAsyncProcess ap = new MyAsyncProcess(conn, CONF);
     SimpleRequestController controller = (SimpleRequestController) ap.requestController;
-    List<Put> puts = new ArrayList<Put>();
+    List<Put> puts = new ArrayList<Put>(1);
     puts.add(createPut(1, true));
 
     for (int i = 0; i != controller.maxConcurrentTasksPerRegion; ++i) {
@@ -747,7 +747,7 @@ public class TestAsyncProcess {
     SimpleRequestController controller = (SimpleRequestController) ap.requestController;
     controller.taskCounterPerServer.put(sn2, new AtomicInteger(controller.maxConcurrentTasksPerServer));
 
-    List<Put> puts = new ArrayList<Put>();
+    List<Put> puts = new ArrayList<Put>(4);
     puts.add(createPut(1, true));
     puts.add(createPut(3, true)); // <== this one won't be taken, the rs is busy
     puts.add(createPut(1, true)); // <== this one will make it, the region is already in
@@ -769,7 +769,7 @@ public class TestAsyncProcess {
   public void testFail() throws Exception {
     MyAsyncProcess ap = new MyAsyncProcess(createHConnection(), CONF, false);
 
-    List<Put> puts = new ArrayList<Put>();
+    List<Put> puts = new ArrayList<Put>(1);
     Put p = createPut(1, false);
     puts.add(p);
 
@@ -817,7 +817,7 @@ public class TestAsyncProcess {
       }
     };
 
-    List<Put> puts = new ArrayList<Put>();
+    List<Put> puts = new ArrayList<Put>(1);
     Put p = createPut(1, true);
     puts.add(p);
 
@@ -843,7 +843,7 @@ public class TestAsyncProcess {
   public void testFailAndSuccess() throws Exception {
     MyAsyncProcess ap = new MyAsyncProcess(createHConnection(), CONF, false);
 
-    List<Put> puts = new ArrayList<Put>();
+    List<Put> puts = new ArrayList<Put>(3);
     puts.add(createPut(1, false));
     puts.add(createPut(1, true));
     puts.add(createPut(1, true));
@@ -870,7 +870,7 @@ public class TestAsyncProcess {
   public void testFlush() throws Exception {
     MyAsyncProcess ap = new MyAsyncProcess(createHConnection(), CONF, false);
 
-    List<Put> puts = new ArrayList<Put>();
+    List<Put> puts = new ArrayList<Put>(3);
     puts.add(createPut(1, false));
     puts.add(createPut(1, true));
     puts.add(createPut(1, true));
@@ -955,7 +955,7 @@ public class TestAsyncProcess {
       }
     };
 
-    List<Put> puts = new ArrayList<Put>();
+    List<Put> puts = new ArrayList<Put>(1);
     puts.add(createPut(1, true));
 
     t.start();
@@ -1171,7 +1171,7 @@ public class TestAsyncProcess {
     HTable ht = new HTable(conn, mutator);
     ht.multiAp = new MyAsyncProcess(conn, CONF, false);
 
-    List<Put> puts = new ArrayList<Put>();
+    List<Put> puts = new ArrayList<Put>(7);
     puts.add(createPut(1, true));
     puts.add(createPut(1, true));
     puts.add(createPut(1, true));
@@ -1517,7 +1517,7 @@ public class TestAsyncProcess {
   }
 
   private static List<Get> makeTimelineGets(byte[]... rows) {
-    List<Get> result = new ArrayList<Get>();
+    List<Get> result = new ArrayList<Get>(rows.length);
     for (byte[] row : rows) {
       Get get = new Get(row);
       get.setConsistency(Consistency.TIMELINE);
@@ -1611,7 +1611,7 @@ public class TestAsyncProcess {
             new LinkedBlockingQueue<Runnable>(200));
     AsyncProcess ap = new AsyncProcessForThrowableCheck(hc, CONF);
 
-    List<Put> puts = new ArrayList<Put>();
+    List<Put> puts = new ArrayList<Put>(1);
     puts.add(createPut(1, true));
     AsyncProcessTask task = AsyncProcessTask.newBuilder()
             .setPool(myPool)

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/test/java/org/apache/hadoop/hbase/filter/TestKeyOnlyFilter.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/test/java/org/apache/hadoop/hbase/filter/TestKeyOnlyFilter.java b/hbase-client/src/test/java/org/apache/hadoop/hbase/filter/TestKeyOnlyFilter.java
index 0e88c4c..e93319a 100644
--- a/hbase-client/src/test/java/org/apache/hadoop/hbase/filter/TestKeyOnlyFilter.java
+++ b/hbase-client/src/test/java/org/apache/hadoop/hbase/filter/TestKeyOnlyFilter.java
@@ -48,7 +48,7 @@ public class TestKeyOnlyFilter {
 
   @Parameters
   public static Collection<Object[]> parameters() {
-    List<Object[]> paramList = new ArrayList<Object[]>();
+    List<Object[]> paramList = new ArrayList<Object[]>(2);
     {
       paramList.add(new Object[] { false });
       paramList.add(new Object[] { true });

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-client/src/test/java/org/apache/hadoop/hbase/ipc/TestHBaseRpcControllerImpl.java
----------------------------------------------------------------------
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 d9535a6..0659f30 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
@@ -39,8 +39,9 @@ public class TestHBaseRpcControllerImpl {
 
   @Test
   public void testListOfCellScannerables() throws IOException {
-    List<CellScannable> cells = new ArrayList<CellScannable>();
     final int count = 10;
+    List<CellScannable> cells = new ArrayList<CellScannable>(count);
+
     for (int i = 0; i < count; i++) {
       cells.add(createCell(i));
     }

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-common/src/main/java/org/apache/hadoop/hbase/ChoreService.java
----------------------------------------------------------------------
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/ChoreService.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/ChoreService.java
index 1623c10..99dc163 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/ChoreService.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/ChoreService.java
@@ -348,7 +348,7 @@ public class ChoreService implements ChoreServicer {
   }
 
   private void cancelAllChores(final boolean mayInterruptIfRunning) {
-    ArrayList<ScheduledChore> choresToCancel = new ArrayList<ScheduledChore>();
+    ArrayList<ScheduledChore> choresToCancel = new ArrayList<ScheduledChore>(scheduledChores.keySet().size());
     // Build list of chores to cancel so we can iterate through a set that won't change
     // as chores are cancelled. If we tried to cancel each chore while iterating through
     // keySet the results would be undefined because the keySet would be changing

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-common/src/main/java/org/apache/hadoop/hbase/KeyValue.java
----------------------------------------------------------------------
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 51038ed..0434820 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
@@ -1184,7 +1184,7 @@ public class KeyValue implements ExtendedCell {
     stringMap.put("vlen", getValueLength());
     List<Tag> tags = getTags();
     if (tags != null) {
-      List<String> tagsString = new ArrayList<String>();
+      List<String> tagsString = new ArrayList<String>(tags.size());
       for (Tag t : tags) {
         tagsString.add(t.toString());
       }

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-common/src/main/java/org/apache/hadoop/hbase/util/AbstractHBaseTool.java
----------------------------------------------------------------------
diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/util/AbstractHBaseTool.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/util/AbstractHBaseTool.java
index a790920..a51a80f 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/util/AbstractHBaseTool.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/util/AbstractHBaseTool.java
@@ -116,7 +116,7 @@ public abstract class AbstractHBaseTool implements Tool, Configurable {
     }
 
     CommandLine cmd;
-    List<String> argsList = new ArrayList<>();
+    List<String> argsList = new ArrayList<>(args.length);
     for (String arg : args) {
       argsList.add(arg);
     }

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-common/src/test/java/org/apache/hadoop/hbase/ResourceChecker.java
----------------------------------------------------------------------
diff --git a/hbase-common/src/test/java/org/apache/hadoop/hbase/ResourceChecker.java b/hbase-common/src/test/java/org/apache/hadoop/hbase/ResourceChecker.java
index ee0380a..310a2fb 100644
--- a/hbase-common/src/test/java/org/apache/hadoop/hbase/ResourceChecker.java
+++ b/hbase-common/src/test/java/org/apache/hadoop/hbase/ResourceChecker.java
@@ -180,7 +180,7 @@ public class ResourceChecker {
    * - logs them.
    */
   public void start() {
-    if (ras.size() == 0) {
+    if (ras.isEmpty()) {
       LOG.info("No resource analyzer");
       return;
     }
@@ -197,7 +197,7 @@ public class ResourceChecker {
    * - logs them.
    */
   public void end() {
-    if (ras.size() == 0) {
+    if (ras.isEmpty()) {
       LOG.info("No resource analyzer");
       return;
     }

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-common/src/test/java/org/apache/hadoop/hbase/util/ClassLoaderTestHelper.java
----------------------------------------------------------------------
diff --git a/hbase-common/src/test/java/org/apache/hadoop/hbase/util/ClassLoaderTestHelper.java b/hbase-common/src/test/java/org/apache/hadoop/hbase/util/ClassLoaderTestHelper.java
index ef213ee..30e33d9 100644
--- a/hbase-common/src/test/java/org/apache/hadoop/hbase/util/ClassLoaderTestHelper.java
+++ b/hbase-common/src/test/java/org/apache/hadoop/hbase/util/ClassLoaderTestHelper.java
@@ -133,13 +133,13 @@ public class ClassLoaderTestHelper {
 
     // compile it by JavaCompiler
     JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
-    ArrayList<String> srcFileNames = new ArrayList<String>();
+    ArrayList<String> srcFileNames = new ArrayList<String>(1);
     srcFileNames.add(sourceCodeFile.toString());
     StandardJavaFileManager fm = compiler.getStandardFileManager(null, null,
       null);
     Iterable<? extends JavaFileObject> cu =
       fm.getJavaFileObjects(sourceCodeFile);
-    List<String> options = new ArrayList<String>();
+    List<String> options = new ArrayList<String>(2);
     options.add("-classpath");
     // only add hbase classes to classpath. This is a little bit tricky: assume
     // the classpath is {hbaseSrc}/target/classes.

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-common/src/test/java/org/apache/hadoop/hbase/util/TestBytes.java
----------------------------------------------------------------------
diff --git a/hbase-common/src/test/java/org/apache/hadoop/hbase/util/TestBytes.java b/hbase-common/src/test/java/org/apache/hadoop/hbase/util/TestBytes.java
index 42afb28..e145642 100644
--- a/hbase-common/src/test/java/org/apache/hadoop/hbase/util/TestBytes.java
+++ b/hbase-common/src/test/java/org/apache/hadoop/hbase/util/TestBytes.java
@@ -498,7 +498,7 @@ public class TestBytes extends TestCase {
   }
   
   public void testToFromHex() {
-    List<String> testStrings = new ArrayList<String>();
+    List<String> testStrings = new ArrayList<String>(8);
     testStrings.addAll(Arrays.asList(new String[] {
         "",
         "00",
@@ -517,7 +517,7 @@ public class TestBytes extends TestCase {
       Assert.assertTrue(testString.equalsIgnoreCase(result));
     }
     
-    List<byte[]> testByteData = new ArrayList<byte[]>();
+    List<byte[]> testByteData = new ArrayList<byte[]>(5);
     testByteData.addAll(Arrays.asList(new byte[][] {
       new byte[0],
       new byte[1],

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-endpoint/src/main/java/org/apache/hadoop/hbase/client/coprocessor/AggregationClient.java
----------------------------------------------------------------------
diff --git a/hbase-endpoint/src/main/java/org/apache/hadoop/hbase/client/coprocessor/AggregationClient.java b/hbase-endpoint/src/main/java/org/apache/hadoop/hbase/client/coprocessor/AggregationClient.java
index d236342..1eda730 100644
--- a/hbase-endpoint/src/main/java/org/apache/hadoop/hbase/client/coprocessor/AggregationClient.java
+++ b/hbase-endpoint/src/main/java/org/apache/hadoop/hbase/client/coprocessor/AggregationClient.java
@@ -587,7 +587,7 @@ public class AggregationClient implements Closeable {
       S sumVal = null, sumSqVal = null;
 
       public synchronized Pair<List<S>, Long> getStdParams() {
-        List<S> l = new ArrayList<S>();
+        List<S> l = new ArrayList<S>(2);
         l.add(sumVal);
         l.add(sumSqVal);
         Pair<List<S>, Long> p = new Pair<List<S>, Long>(l, rowCountVal);
@@ -704,7 +704,7 @@ public class AggregationClient implements Closeable {
       S sumVal = null, sumWeights = null;
 
       public synchronized Pair<NavigableMap<byte[], List<S>>, List<S>> getMedianParams() {
-        List<S> l = new ArrayList<S>();
+        List<S> l = new ArrayList<S>(2);
         l.add(sumVal);
         l.add(sumWeights);
         Pair<NavigableMap<byte[], List<S>>, List<S>> p =

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-endpoint/src/test/java/org/apache/hadoop/hbase/coprocessor/TestRowProcessorEndpoint.java
----------------------------------------------------------------------
diff --git a/hbase-endpoint/src/test/java/org/apache/hadoop/hbase/coprocessor/TestRowProcessorEndpoint.java b/hbase-endpoint/src/test/java/org/apache/hadoop/hbase/coprocessor/TestRowProcessorEndpoint.java
index ade738e..7bb6e2b 100644
--- a/hbase-endpoint/src/test/java/org/apache/hadoop/hbase/coprocessor/TestRowProcessorEndpoint.java
+++ b/hbase-endpoint/src/test/java/org/apache/hadoop/hbase/coprocessor/TestRowProcessorEndpoint.java
@@ -353,7 +353,7 @@ public class TestRowProcessorEndpoint {
         Scan scan = new Scan(row, row);
         scan.addColumn(FAM, COUNTER);
         doScan(region, scan, kvs);
-        counter = kvs.size() == 0 ? 0 :
+        counter = kvs.isEmpty() ? 0 :
           Bytes.toInt(CellUtil.cloneValue(kvs.iterator().next()));
 
         // Assert counter value
@@ -497,7 +497,7 @@ public class TestRowProcessorEndpoint {
 
       @Override
       public Collection<byte[]> getRowsToLock() {
-        List<byte[]> rows = new ArrayList<byte[]>();
+        List<byte[]> rows = new ArrayList<byte[]>(2);
         rows.add(row1);
         rows.add(row2);
         return rows;
@@ -538,7 +538,7 @@ public class TestRowProcessorEndpoint {
         swapped = !swapped;
 
         // Add and delete keyvalues
-        List<List<Cell>> kvs = new ArrayList<List<Cell>>();
+        List<List<Cell>> kvs = new ArrayList<List<Cell>>(2);
         kvs.add(kvs1);
         kvs.add(kvs2);
         byte[][] rows = new byte[][]{row1, row2};

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-endpoint/src/test/java/org/apache/hadoop/hbase/regionserver/SecureBulkLoadEndpointClient.java
----------------------------------------------------------------------
diff --git a/hbase-endpoint/src/test/java/org/apache/hadoop/hbase/regionserver/SecureBulkLoadEndpointClient.java b/hbase-endpoint/src/test/java/org/apache/hadoop/hbase/regionserver/SecureBulkLoadEndpointClient.java
index a82900d..06e45eb 100644
--- a/hbase-endpoint/src/test/java/org/apache/hadoop/hbase/regionserver/SecureBulkLoadEndpointClient.java
+++ b/hbase-endpoint/src/test/java/org/apache/hadoop/hbase/regionserver/SecureBulkLoadEndpointClient.java
@@ -133,7 +133,7 @@ public class SecureBulkLoadEndpointClient {
       }
 
       List<ClientProtos.BulkLoadHFileRequest.FamilyPath> protoFamilyPaths =
-          new ArrayList<ClientProtos.BulkLoadHFileRequest.FamilyPath>();
+          new ArrayList<ClientProtos.BulkLoadHFileRequest.FamilyPath>(familyPaths.size());
       for(Pair<byte[], String> el: familyPaths) {
         protoFamilyPaths.add(ClientProtos.BulkLoadHFileRequest.FamilyPath.newBuilder()
           .setFamily(ByteStringer.wrap(el.getFirst()))

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-examples/src/main/java/org/apache/hadoop/hbase/thrift/DemoClient.java
----------------------------------------------------------------------
diff --git a/hbase-examples/src/main/java/org/apache/hadoop/hbase/thrift/DemoClient.java b/hbase-examples/src/main/java/org/apache/hadoop/hbase/thrift/DemoClient.java
index 64adc93..b16ef7b 100644
--- a/hbase-examples/src/main/java/org/apache/hadoop/hbase/thrift/DemoClient.java
+++ b/hbase-examples/src/main/java/org/apache/hadoop/hbase/thrift/DemoClient.java
@@ -154,7 +154,7 @@ public class DemoClient {
         //
         // Create the demo table with two column families, entry: and unused:
         //
-        ArrayList<ColumnDescriptor> columns = new ArrayList<ColumnDescriptor>();
+        ArrayList<ColumnDescriptor> columns = new ArrayList<ColumnDescriptor>(2);
         ColumnDescriptor col;
         col = new ColumnDescriptor();
         col.name = ByteBuffer.wrap(bytes("entry:"));
@@ -194,7 +194,7 @@ public class DemoClient {
 
         ArrayList<Mutation> mutations;
         // non-utf8 is fine for data
-        mutations = new ArrayList<Mutation>();
+        mutations = new ArrayList<Mutation>(1);
         mutations.add(new Mutation(false, ByteBuffer.wrap(bytes("entry:foo")),
             ByteBuffer.wrap(invalid), writeToWal));
         client.mutateRow(ByteBuffer.wrap(t), ByteBuffer.wrap(bytes("foo")),
@@ -202,13 +202,13 @@ public class DemoClient {
 
 
         // this row name is valid utf8
-        mutations = new ArrayList<Mutation>();
+        mutations = new ArrayList<Mutation>(1);
         mutations.add(new Mutation(false, ByteBuffer.wrap(bytes("entry:foo")), ByteBuffer.wrap(valid), writeToWal));
         client.mutateRow(ByteBuffer.wrap(t), ByteBuffer.wrap(valid), mutations, dummyAttributes);
 
         // non-utf8 is now allowed in row names because HBase stores values as binary
 
-        mutations = new ArrayList<Mutation>();
+        mutations = new ArrayList<Mutation>(1);
         mutations.add(new Mutation(false, ByteBuffer.wrap(bytes("entry:foo")), ByteBuffer.wrap(invalid), writeToWal));
         client.mutateRow(ByteBuffer.wrap(t), ByteBuffer.wrap(invalid), mutations, dummyAttributes);
 
@@ -238,7 +238,7 @@ public class DemoClient {
             nf.setGroupingUsed(false);
             byte[] row = bytes(nf.format(i));
 
-            mutations = new ArrayList<Mutation>();
+            mutations = new ArrayList<Mutation>(1);
             mutations.add(new Mutation(false, ByteBuffer.wrap(bytes("unused:")), ByteBuffer.wrap(bytes("DELETE_ME")), writeToWal));
             client.mutateRow(ByteBuffer.wrap(t), ByteBuffer.wrap(row), mutations, dummyAttributes);
             printRow(client.getRow(ByteBuffer.wrap(t), ByteBuffer.wrap(row), dummyAttributes));
@@ -251,14 +251,14 @@ public class DemoClient {
                 // no-op
             }
 
-            mutations = new ArrayList<Mutation>();
+            mutations = new ArrayList<Mutation>(2);
             mutations.add(new Mutation(false, ByteBuffer.wrap(bytes("entry:num")), ByteBuffer.wrap(bytes("0")), writeToWal));
             mutations.add(new Mutation(false, ByteBuffer.wrap(bytes("entry:foo")), ByteBuffer.wrap(bytes("FOO")), writeToWal));
             client.mutateRow(ByteBuffer.wrap(t), ByteBuffer.wrap(row), mutations, dummyAttributes);
             printRow(client.getRow(ByteBuffer.wrap(t), ByteBuffer.wrap(row), dummyAttributes));
 
             Mutation m;
-            mutations = new ArrayList<Mutation>();
+            mutations = new ArrayList<Mutation>(2);
             m = new Mutation();
             m.column = ByteBuffer.wrap(bytes("entry:foo"));
             m.isDelete = true;

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-examples/src/main/java/org/apache/hadoop/hbase/thrift/HttpDoAsClient.java
----------------------------------------------------------------------
diff --git a/hbase-examples/src/main/java/org/apache/hadoop/hbase/thrift/HttpDoAsClient.java b/hbase-examples/src/main/java/org/apache/hadoop/hbase/thrift/HttpDoAsClient.java
index df18fed..666891c 100644
--- a/hbase-examples/src/main/java/org/apache/hadoop/hbase/thrift/HttpDoAsClient.java
+++ b/hbase-examples/src/main/java/org/apache/hadoop/hbase/thrift/HttpDoAsClient.java
@@ -151,7 +151,7 @@ public class HttpDoAsClient {
     //
     // Create the demo table with two column families, entry: and unused:
     //
-    ArrayList<ColumnDescriptor> columns = new ArrayList<ColumnDescriptor>();
+    ArrayList<ColumnDescriptor> columns = new ArrayList<ColumnDescriptor>(2);
     ColumnDescriptor col;
     col = new ColumnDescriptor();
     col.name = ByteBuffer.wrap(bytes("entry:"));

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-examples/src/main/java/org/apache/hadoop/hbase/thrift2/DemoClient.java
----------------------------------------------------------------------
diff --git a/hbase-examples/src/main/java/org/apache/hadoop/hbase/thrift2/DemoClient.java b/hbase-examples/src/main/java/org/apache/hadoop/hbase/thrift2/DemoClient.java
index e96688e..4083792 100644
--- a/hbase-examples/src/main/java/org/apache/hadoop/hbase/thrift2/DemoClient.java
+++ b/hbase-examples/src/main/java/org/apache/hadoop/hbase/thrift2/DemoClient.java
@@ -126,7 +126,7 @@ public class DemoClient {
     columnValue.setFamily("family1".getBytes());
     columnValue.setQualifier("qualifier1".getBytes());
     columnValue.setValue("value1".getBytes());
-    List<TColumnValue> columnValues = new ArrayList<TColumnValue>();
+    List<TColumnValue> columnValues = new ArrayList<TColumnValue>(1);
     columnValues.add(columnValue);
     put.setColumnValues(columnValues);
 

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-hadoop2-compat/src/main/java/org/apache/hadoop/metrics2/util/MetricSampleQuantiles.java
----------------------------------------------------------------------
diff --git a/hbase-hadoop2-compat/src/main/java/org/apache/hadoop/metrics2/util/MetricSampleQuantiles.java b/hbase-hadoop2-compat/src/main/java/org/apache/hadoop/metrics2/util/MetricSampleQuantiles.java
index 96c79ae..a968aca 100644
--- a/hbase-hadoop2-compat/src/main/java/org/apache/hadoop/metrics2/util/MetricSampleQuantiles.java
+++ b/hbase-hadoop2-compat/src/main/java/org/apache/hadoop/metrics2/util/MetricSampleQuantiles.java
@@ -134,7 +134,7 @@ public class MetricSampleQuantiles {
 
     // Base case: no samples
     int start = 0;
-    if (samples.size() == 0) {
+    if (samples.isEmpty()) {
       SampleItem newItem = new SampleItem(buffer[0], 1, 0);
       samples.add(newItem);
       start++;
@@ -203,7 +203,7 @@ public class MetricSampleQuantiles {
    * @return Estimated value at that quantile.
    */
   private long query(double quantile) throws IOException {
-    if (samples.size() == 0) {
+    if (samples.isEmpty()) {
       throw new IOException("No samples present");
     }
 

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-it/src/test/java/org/apache/hadoop/hbase/IntegrationTestDDLMasterFailover.java
----------------------------------------------------------------------
diff --git a/hbase-it/src/test/java/org/apache/hadoop/hbase/IntegrationTestDDLMasterFailover.java b/hbase-it/src/test/java/org/apache/hadoop/hbase/IntegrationTestDDLMasterFailover.java
index 59cb8dd..5d79722 100644
--- a/hbase-it/src/test/java/org/apache/hadoop/hbase/IntegrationTestDDLMasterFailover.java
+++ b/hbase-it/src/test/java/org/apache/hadoop/hbase/IntegrationTestDDLMasterFailover.java
@@ -924,7 +924,7 @@ public class IntegrationTestDDLMasterFailover extends IntegrationTestBase {
     String numThreadKey = String.format(NUM_THREADS_KEY, this.getClass().getSimpleName());
     numThreads = util.getConfiguration().getInt(numThreadKey, DEFAULT_NUM_THREADS);
 
-    ArrayList<Worker> workers = new ArrayList<>();
+    ArrayList<Worker> workers = new ArrayList<>(numThreads);
     for (int i = 0; i < numThreads; i++) {
       checkException(workers);
       Worker worker = new Worker();

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-it/src/test/java/org/apache/hadoop/hbase/IntegrationTestIngest.java
----------------------------------------------------------------------
diff --git a/hbase-it/src/test/java/org/apache/hadoop/hbase/IntegrationTestIngest.java b/hbase-it/src/test/java/org/apache/hadoop/hbase/IntegrationTestIngest.java
index 0df4927..5c41fa0 100644
--- a/hbase-it/src/test/java/org/apache/hadoop/hbase/IntegrationTestIngest.java
+++ b/hbase-it/src/test/java/org/apache/hadoop/hbase/IntegrationTestIngest.java
@@ -225,7 +225,7 @@ public class IntegrationTestIngest extends IntegrationTestBase {
 
   protected String[] getArgsForLoadTestTool(String mode, String modeSpecificArg, long startKey,
       long numKeys) {
-    List<String> args = new ArrayList<String>();
+    List<String> args = new ArrayList<String>(11);
     args.add("-tn");
     args.add(getTablename().getNameAsString());
     args.add("-families");

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-it/src/test/java/org/apache/hadoop/hbase/IntegrationTestIngestWithVisibilityLabels.java
----------------------------------------------------------------------
diff --git a/hbase-it/src/test/java/org/apache/hadoop/hbase/IntegrationTestIngestWithVisibilityLabels.java b/hbase-it/src/test/java/org/apache/hadoop/hbase/IntegrationTestIngestWithVisibilityLabels.java
index b942918..133be1a 100644
--- a/hbase-it/src/test/java/org/apache/hadoop/hbase/IntegrationTestIngestWithVisibilityLabels.java
+++ b/hbase-it/src/test/java/org/apache/hadoop/hbase/IntegrationTestIngestWithVisibilityLabels.java
@@ -45,28 +45,28 @@ public class IntegrationTestIngestWithVisibilityLabels extends IntegrationTestIn
   private static final List<List<String>> AUTHS = new ArrayList<List<String>>();
 
   static {
-    ArrayList<String> tmp = new ArrayList<String>();
+    ArrayList<String> tmp = new ArrayList<String>(2);
     tmp.add("secret");
     tmp.add("confidential");
     AUTHS.add(tmp);
-    tmp = new ArrayList<String>();
+    tmp = new ArrayList<String>(1);
     tmp.add("topsecret");
     AUTHS.add(tmp);
-    tmp = new ArrayList<String>();
+    tmp = new ArrayList<String>(2);
     tmp.add("confidential");
     tmp.add("private");
     AUTHS.add(tmp);
-    tmp = new ArrayList<String>();
+    tmp = new ArrayList<String>(1);
     tmp.add("public");
     AUTHS.add(tmp);
-    tmp = new ArrayList<String>();
+    tmp = new ArrayList<String>(2);
     tmp.add("topsecret");
     tmp.add("private");
     AUTHS.add(tmp);
-    tmp = new ArrayList<String>();
+    tmp = new ArrayList<String>(1);
     tmp.add("confidential");
     AUTHS.add(tmp);
-    tmp = new ArrayList<String>();
+    tmp = new ArrayList<String>(2);
     tmp.add("topsecret");
     tmp.add("private");
     AUTHS.add(tmp);

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-it/src/test/java/org/apache/hadoop/hbase/ipc/IntegrationTestRpcClient.java
----------------------------------------------------------------------
diff --git a/hbase-it/src/test/java/org/apache/hadoop/hbase/ipc/IntegrationTestRpcClient.java b/hbase-it/src/test/java/org/apache/hadoop/hbase/ipc/IntegrationTestRpcClient.java
index 219a4e0..df83731 100644
--- a/hbase-it/src/test/java/org/apache/hadoop/hbase/ipc/IntegrationTestRpcClient.java
+++ b/hbase-it/src/test/java/org/apache/hadoop/hbase/ipc/IntegrationTestRpcClient.java
@@ -392,7 +392,7 @@ public class IntegrationTestRpcClient {
       cluster.startServer();
     }
 
-    ArrayList<SimpleClient> clients = new ArrayList<>();
+    ArrayList<SimpleClient> clients = new ArrayList<>(30);
 
     // all threads should share the same rpc client
     AbstractRpcClient<?> rpcClient = createRpcClient(conf, isSyncClient);

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-it/src/test/java/org/apache/hadoop/hbase/test/IntegrationTestBigLinkedList.java
----------------------------------------------------------------------
diff --git a/hbase-it/src/test/java/org/apache/hadoop/hbase/test/IntegrationTestBigLinkedList.java b/hbase-it/src/test/java/org/apache/hadoop/hbase/test/IntegrationTestBigLinkedList.java
index 135bea7..841d7d0 100644
--- a/hbase-it/src/test/java/org/apache/hadoop/hbase/test/IntegrationTestBigLinkedList.java
+++ b/hbase-it/src/test/java/org/apache/hadoop/hbase/test/IntegrationTestBigLinkedList.java
@@ -1181,7 +1181,7 @@ public class IntegrationTestBigLinkedList extends IntegrationTestBase {
             // useless for debugging.
             context.getCounter("undef", keyString).increment(1);
           }
-        } else if (defCount > 0 && refs.size() == 0) {
+        } else if (defCount > 0 && refs.isEmpty()) {
           // node is defined but not referenced
           context.write(key, UNREF);
           context.getCounter(Counts.UNREFERENCED).increment(1);

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/row/data/TestRowDataExerciseFInts.java
----------------------------------------------------------------------
diff --git a/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/row/data/TestRowDataExerciseFInts.java b/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/row/data/TestRowDataExerciseFInts.java
index c49db13..39140a3 100644
--- a/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/row/data/TestRowDataExerciseFInts.java
+++ b/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/row/data/TestRowDataExerciseFInts.java
@@ -43,7 +43,7 @@ public class TestRowDataExerciseFInts extends BaseTestRowData{
 
   static List<ByteRange> rows;
   static{
-    List<String> rowStrings = new ArrayList<String>();
+    List<String> rowStrings = new ArrayList<String>(16);
     rowStrings.add("com.edsBlog/directoryAa/pageAaa");
     rowStrings.add("com.edsBlog/directoryAa/pageBbb");
     rowStrings.add("com.edsBlog/directoryAa/pageCcc");

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/row/data/TestRowDataTrivialWithTags.java
----------------------------------------------------------------------
diff --git a/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/row/data/TestRowDataTrivialWithTags.java b/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/row/data/TestRowDataTrivialWithTags.java
index a615155..2d3901f 100644
--- a/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/row/data/TestRowDataTrivialWithTags.java
+++ b/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/row/data/TestRowDataTrivialWithTags.java
@@ -46,7 +46,7 @@ public class TestRowDataTrivialWithTags extends BaseTestRowData{
 
   static List<KeyValue> d = Lists.newArrayList();
   static {
-    List<Tag> tagList = new ArrayList<Tag>();
+    List<Tag> tagList = new ArrayList<Tag>(2);
     Tag t = new ArrayBackedTag((byte) 1, "visisbility");
     tagList.add(t);
     t = new ArrayBackedTag((byte) 2, "ACL");

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/row/data/TestRowDataUrls.java
----------------------------------------------------------------------
diff --git a/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/row/data/TestRowDataUrls.java b/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/row/data/TestRowDataUrls.java
index 74ac85a..a71daaa 100644
--- a/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/row/data/TestRowDataUrls.java
+++ b/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/row/data/TestRowDataUrls.java
@@ -41,7 +41,7 @@ public class TestRowDataUrls extends BaseTestRowData{
 
   static List<ByteRange> rows;
   static{
-    List<String> rowStrings = new ArrayList<String>();
+    List<String> rowStrings = new ArrayList<String>(16);
     rowStrings.add("com.edsBlog/directoryAa/pageAaa");
     rowStrings.add("com.edsBlog/directoryAa/pageBbb");
     rowStrings.add("com.edsBlog/directoryAa/pageCcc");

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/timestamp/data/TestTimestampDataBasic.java
----------------------------------------------------------------------
diff --git a/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/timestamp/data/TestTimestampDataBasic.java b/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/timestamp/data/TestTimestampDataBasic.java
index f11fab4..bccff6d 100644
--- a/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/timestamp/data/TestTimestampDataBasic.java
+++ b/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/timestamp/data/TestTimestampDataBasic.java
@@ -27,7 +27,7 @@ public class TestTimestampDataBasic implements TestTimestampData {
 
   @Override
   public List<Long> getInputs() {
-    List<Long> d = new ArrayList<Long>();
+    List<Long> d = new ArrayList<Long>(5);
     d.add(5L);
     d.add(3L);
     d.add(0L);
@@ -43,7 +43,7 @@ public class TestTimestampDataBasic implements TestTimestampData {
 
   @Override
   public List<Long> getOutputs() {
-    List<Long> d = new ArrayList<Long>();
+    List<Long> d = new ArrayList<Long>(4);
     d.add(0L);
     d.add(1L);
     d.add(3L);

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/timestamp/data/TestTimestampDataNumbers.java
----------------------------------------------------------------------
diff --git a/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/timestamp/data/TestTimestampDataNumbers.java b/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/timestamp/data/TestTimestampDataNumbers.java
index f5ed89d..2a5dcae 100644
--- a/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/timestamp/data/TestTimestampDataNumbers.java
+++ b/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/timestamp/data/TestTimestampDataNumbers.java
@@ -29,7 +29,7 @@ public class TestTimestampDataNumbers implements TestTimestampData {
 
   @Override
   public List<Long> getInputs() {
-    List<Long> d = new ArrayList<Long>();
+    List<Long> d = new ArrayList<Long>(5);
     d.add(5L << shift);
     d.add(3L << shift);
     d.add(7L << shift);
@@ -45,7 +45,7 @@ public class TestTimestampDataNumbers implements TestTimestampData {
 
   @Override
   public List<Long> getOutputs() {
-    List<Long> d = new ArrayList<Long>();
+    List<Long> d = new ArrayList<Long>(4);
     d.add(1L << shift);
     d.add(3L << shift);
     d.add(5L << shift);

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/timestamp/data/TestTimestampDataRepeats.java
----------------------------------------------------------------------
diff --git a/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/timestamp/data/TestTimestampDataRepeats.java b/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/timestamp/data/TestTimestampDataRepeats.java
index 69548d2..2186528 100644
--- a/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/timestamp/data/TestTimestampDataRepeats.java
+++ b/hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/timestamp/data/TestTimestampDataRepeats.java
@@ -29,7 +29,7 @@ public class TestTimestampDataRepeats implements TestTimestampData {
 
   @Override
   public List<Long> getInputs() {
-    List<Long> d = new ArrayList<Long>();
+    List<Long> d = new ArrayList<Long>(5);
     d.add(t);
     d.add(t);
     d.add(t);

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-procedure/src/main/java/org/apache/hadoop/hbase/procedure2/store/wal/ProcedureWALPrettyPrinter.java
----------------------------------------------------------------------
diff --git a/hbase-procedure/src/main/java/org/apache/hadoop/hbase/procedure2/store/wal/ProcedureWALPrettyPrinter.java b/hbase-procedure/src/main/java/org/apache/hadoop/hbase/procedure2/store/wal/ProcedureWALPrettyPrinter.java
index 5f7db95..ec59607 100644
--- a/hbase-procedure/src/main/java/org/apache/hadoop/hbase/procedure2/store/wal/ProcedureWALPrettyPrinter.java
+++ b/hbase-procedure/src/main/java/org/apache/hadoop/hbase/procedure2/store/wal/ProcedureWALPrettyPrinter.java
@@ -163,7 +163,7 @@ public class ProcedureWALPrettyPrinter extends Configured implements Tool {
         files.add(new Path(cmd.getOptionValue("f")));
       }
 
-      if (files.size() == 0 || cmd.hasOption("h")) {
+      if (files.isEmpty() || cmd.hasOption("h")) {
         HelpFormatter formatter = new HelpFormatter();
         formatter.printHelp("ProcedureWALPrettyPrinter ", options, true);
         return(-1);

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/MultiRowResource.java
----------------------------------------------------------------------
diff --git a/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/MultiRowResource.java b/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/MultiRowResource.java
index b952c00..f7200cf 100644
--- a/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/MultiRowResource.java
+++ b/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/MultiRowResource.java
@@ -105,7 +105,7 @@ public class MultiRowResource extends ResourceBase implements Constants {
         }
       }
 
-      if (model.getRows().size() == 0) {
+      if (model.getRows().isEmpty()) {
       //If no rows found.
         servlet.getMetrics().incrementFailedGetRequests(1);
         return Response.status(Response.Status.NOT_FOUND)

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/client/RemoteHTable.java
----------------------------------------------------------------------
diff --git a/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/client/RemoteHTable.java b/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/client/RemoteHTable.java
index 5debf39..51a75d7 100644
--- a/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/client/RemoteHTable.java
+++ b/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/client/RemoteHTable.java
@@ -175,7 +175,7 @@ public class RemoteHTable implements Table {
   protected Result[] buildResultFromModel(final CellSetModel model) {
     List<Result> results = new ArrayList<Result>();
     for (RowModel row: model.getRows()) {
-      List<Cell> kvs = new ArrayList<Cell>();
+      List<Cell> kvs = new ArrayList<Cell>(row.getCells().size());
       for (CellModel cell: row.getCells()) {
         byte[][] split = KeyValue.parseColumn(cell.getColumn());
         byte[] column = split[0];

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/model/NamespacesInstanceModel.java
----------------------------------------------------------------------
diff --git a/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/model/NamespacesInstanceModel.java b/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/model/NamespacesInstanceModel.java
index b31ecf9..0c5af3c 100644
--- a/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/model/NamespacesInstanceModel.java
+++ b/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/model/NamespacesInstanceModel.java
@@ -87,7 +87,7 @@ public class NamespacesInstanceModel implements Serializable, ProtobufMessageHan
     NamespaceDescriptor nd = admin.getNamespaceDescriptor(namespaceName);
 
     // For properly formed JSON, if no properties, field has to be null (not just no elements).
-    if(nd.getConfiguration().size() == 0){ return; }
+    if(nd.getConfiguration().isEmpty()){ return; }
 
     properties = new HashMap<String,String>();
     properties.putAll(nd.getConfiguration());

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/model/NamespacesModel.java
----------------------------------------------------------------------
diff --git a/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/model/NamespacesModel.java b/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/model/NamespacesModel.java
index d6a5685..aed80aa 100644
--- a/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/model/NamespacesModel.java
+++ b/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/model/NamespacesModel.java
@@ -66,7 +66,7 @@ public class NamespacesModel implements Serializable, ProtobufMessageHandler {
    */
   public NamespacesModel(Admin admin) throws IOException {
     NamespaceDescriptor[] nds = admin.listNamespaceDescriptors();
-    namespaces = new ArrayList<String>();
+    namespaces = new ArrayList<String>(nds.length);
     for (NamespaceDescriptor nd : nds) {
       namespaces.add(nd.getName());
     }

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/model/ScannerModel.java
----------------------------------------------------------------------
diff --git a/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/model/ScannerModel.java b/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/model/ScannerModel.java
index 024fec8..d484633 100644
--- a/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/model/ScannerModel.java
+++ b/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/model/ScannerModel.java
@@ -384,7 +384,7 @@ public class ScannerModel implements ProtobufMessageHandler, Serializable {
         filter = new FamilyFilter(CompareOp.valueOf(op), comparator.build());
         break;
       case FilterList: {
-        List<Filter> list = new ArrayList<Filter>();
+        List<Filter> list = new ArrayList<Filter>(filters.size());
         for (FilterModel model: filters) {
           list.add(model.build());
         }

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestMultiRowResource.java
----------------------------------------------------------------------
diff --git a/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestMultiRowResource.java b/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestMultiRowResource.java
index 84d1855..c1087b5 100644
--- a/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestMultiRowResource.java
+++ b/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestMultiRowResource.java
@@ -82,7 +82,7 @@ public class TestMultiRowResource {
 
   @Parameterized.Parameters
   public static Collection<Object[]> data() {
-    List<Object[]> params = new ArrayList<Object[]>();
+    List<Object[]> params = new ArrayList<Object[]>(2);
     params.add(new Object[] {Boolean.TRUE});
     params.add(new Object[] {Boolean.FALSE});
     return params;

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestScannersWithFilters.java
----------------------------------------------------------------------
diff --git a/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestScannersWithFilters.java b/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestScannersWithFilters.java
index eed4f1a..bedd08e 100644
--- a/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestScannersWithFilters.java
+++ b/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestScannersWithFilters.java
@@ -957,7 +957,7 @@ public class TestScannersWithFilters {
     // Test getting a single row, single key using Row, Qualifier, and Value
     // regular expression and substring filters
     // Use must pass all
-    List<Filter> filters = new ArrayList<Filter>();
+    List<Filter> filters = new ArrayList<Filter>(3);
     filters.add(new RowFilter(CompareOp.EQUAL,
       new RegexStringComparator(".+-2")));
     filters.add(new QualifierFilter(CompareOp.EQUAL,

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestScannersWithLabels.java
----------------------------------------------------------------------
diff --git a/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestScannersWithLabels.java b/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestScannersWithLabels.java
index cb235aa..8b0b5b2 100644
--- a/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestScannersWithLabels.java
+++ b/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestScannersWithLabels.java
@@ -94,7 +94,7 @@ public class TestScannersWithLabels {
     byte[] k = new byte[3];
     byte[][] famAndQf = KeyValue.parseColumn(Bytes.toBytes(column));
 
-    List<Put> puts = new ArrayList<>();
+    List<Put> puts = new ArrayList<>(9);
     for (int i = 0; i < 9; i++) {
       Put put = new Put(Bytes.toBytes("row" + i));
       put.setDurability(Durability.SKIP_WAL);

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestSchemaResource.java
----------------------------------------------------------------------
diff --git a/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestSchemaResource.java b/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestSchemaResource.java
index 19fdaf0..96106e9 100644
--- a/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestSchemaResource.java
+++ b/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/TestSchemaResource.java
@@ -73,7 +73,7 @@ public class TestSchemaResource {
 
   @Parameterized.Parameters
   public static Collection<Object[]> data() {
-    List<Object[]> params = new ArrayList<Object[]>();
+    List<Object[]> params = new ArrayList<Object[]>(2);
     params.add(new Object[] {Boolean.TRUE});
     params.add(new Object[] {Boolean.FALSE});
     return params;

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/client/TestRemoteTable.java
----------------------------------------------------------------------
diff --git a/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/client/TestRemoteTable.java b/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/client/TestRemoteTable.java
index 6d367c7..57f20fd 100644
--- a/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/client/TestRemoteTable.java
+++ b/hbase-rest/src/test/java/org/apache/hadoop/hbase/rest/client/TestRemoteTable.java
@@ -262,7 +262,7 @@ public class TestRemoteTable {
 
   @Test
   public void testMultiGet() throws Exception {
-    ArrayList<Get> gets = new ArrayList<Get>();
+    ArrayList<Get> gets = new ArrayList<Get>(2);
     gets.add(new Get(ROW_1));
     gets.add(new Get(ROW_2));
     Result[] results = remoteTable.get(gets);
@@ -272,7 +272,7 @@ public class TestRemoteTable {
     assertEquals(2, results[1].size());
 
     //Test Versions
-    gets = new ArrayList<Get>();
+    gets = new ArrayList<Get>(2);
     Get g = new Get(ROW_1);
     g.setMaxVersions(3);
     gets.add(g);
@@ -284,13 +284,13 @@ public class TestRemoteTable {
     assertEquals(3, results[1].size());
 
     //404
-    gets = new ArrayList<Get>();
+    gets = new ArrayList<Get>(1);
     gets.add(new Get(Bytes.toBytes("RESALLYREALLYNOTTHERE")));
     results = remoteTable.get(gets);
     assertNotNull(results);
     assertEquals(0, results.length);
 
-    gets = new ArrayList<Get>();
+    gets = new ArrayList<Get>(3);
     gets.add(new Get(Bytes.toBytes("RESALLYREALLYNOTTHERE")));
     gets.add(new Get(ROW_1));
     gets.add(new Get(ROW_2));
@@ -314,7 +314,7 @@ public class TestRemoteTable {
 
     // multiput
 
-    List<Put> puts = new ArrayList<Put>();
+    List<Put> puts = new ArrayList<Put>(3);
     put = new Put(ROW_3);
     put.addColumn(COLUMN_2, QUALIFIER_2, VALUE_2);
     puts.add(put);
@@ -408,7 +408,7 @@ public class TestRemoteTable {
    */
   @Test
   public void testScanner() throws IOException {
-    List<Put> puts = new ArrayList<Put>();
+    List<Put> puts = new ArrayList<Put>(4);
     Put put = new Put(ROW_1);
     put.addColumn(COLUMN_1, QUALIFIER_1, VALUE_1);
     puts.add(put);
@@ -499,7 +499,7 @@ public class TestRemoteTable {
    */
   @Test
   public void testIteratorScaner() throws IOException {
-    List<Put> puts = new ArrayList<Put>();
+    List<Put> puts = new ArrayList<Put>(4);
     Put put = new Put(ROW_1);
     put.addColumn(COLUMN_1, QUALIFIER_1, VALUE_1);
     puts.add(put);

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-rsgroup/src/main/java/org/apache/hadoop/hbase/rsgroup/RSGroupInfoManagerImpl.java
----------------------------------------------------------------------
diff --git a/hbase-rsgroup/src/main/java/org/apache/hadoop/hbase/rsgroup/RSGroupInfoManagerImpl.java b/hbase-rsgroup/src/main/java/org/apache/hadoop/hbase/rsgroup/RSGroupInfoManagerImpl.java
index 47d0c0e..a8de198 100644
--- a/hbase-rsgroup/src/main/java/org/apache/hadoop/hbase/rsgroup/RSGroupInfoManagerImpl.java
+++ b/hbase-rsgroup/src/main/java/org/apache/hadoop/hbase/rsgroup/RSGroupInfoManagerImpl.java
@@ -309,7 +309,7 @@ public class RSGroupInfoManagerImpl implements RSGroupInfoManager, ServerListene
 
     List<TableName> specialTables;
     if(!master.isInitialized()) {
-      specialTables = new ArrayList<TableName>();
+      specialTables = new ArrayList<TableName>(4);
       specialTables.add(AccessControlLists.ACL_TABLE_NAME);
       specialTables.add(TableName.META_TABLE_NAME);
       specialTables.add(TableName.NAMESPACE_TABLE_NAME);

http://git-wip-us.apache.org/repos/asf/hbase/blob/55a1aa1e/hbase-rsgroup/src/test/java/org/apache/hadoop/hbase/rsgroup/TestRSGroupsBase.java
----------------------------------------------------------------------
diff --git a/hbase-rsgroup/src/test/java/org/apache/hadoop/hbase/rsgroup/TestRSGroupsBase.java b/hbase-rsgroup/src/test/java/org/apache/hadoop/hbase/rsgroup/TestRSGroupsBase.java
index a725134..50302bc 100644
--- a/hbase-rsgroup/src/test/java/org/apache/hadoop/hbase/rsgroup/TestRSGroupsBase.java
+++ b/hbase-rsgroup/src/test/java/org/apache/hadoop/hbase/rsgroup/TestRSGroupsBase.java
@@ -589,7 +589,7 @@ public abstract class TestRSGroupsBase {
     TEST_UTIL.waitFor(WAIT_TIMEOUT, new Waiter.Predicate<Exception>() {
       @Override
       public boolean evaluate() throws Exception {
-        return cluster.getClusterStatus().getRegionsInTransition().size() == 0;
+        return cluster.getClusterStatus().getRegionsInTransition().isEmpty();
       }
     });
     Set<HostAndPort> newServers = Sets.newHashSet();
@@ -606,7 +606,7 @@ public abstract class TestRSGroupsBase {
     TEST_UTIL.waitFor(WAIT_TIMEOUT, new Waiter.Predicate<Exception>() {
       @Override
       public boolean evaluate() throws Exception {
-        return cluster.getClusterStatus().getRegionsInTransition().size() == 0;
+        return cluster.getClusterStatus().getRegionsInTransition().isEmpty();
       }
     });