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Posted to commits@tajo.apache.org by hy...@apache.org on 2015/09/23 06:28:55 UTC

[5/5] tajo git commit: TAJO-1844: Eliminate explicit diamond expressions.

TAJO-1844: Eliminate explicit diamond expressions.

Signed-off-by: Hyunsik Choi <hy...@apache.org>


Project: http://git-wip-us.apache.org/repos/asf/tajo/repo
Commit: http://git-wip-us.apache.org/repos/asf/tajo/commit/aa699c70
Tree: http://git-wip-us.apache.org/repos/asf/tajo/tree/aa699c70
Diff: http://git-wip-us.apache.org/repos/asf/tajo/diff/aa699c70

Branch: refs/heads/master
Commit: aa699c70943f7563e77f5828683cd0399998a0f9
Parents: 1eb1004
Author: Dongkyu Hwangbo <hw...@gmail.com>
Authored: Tue Sep 22 21:24:06 2015 -0700
Committer: Hyunsik Choi <hy...@apache.org>
Committed: Tue Sep 22 21:25:07 2015 -0700

----------------------------------------------------------------------
 CHANGES                                         |  3 +
 .../tajo/catalog/AbstractCatalogClient.java     |  2 +-
 .../org/apache/tajo/catalog/CatalogUtil.java    |  6 +-
 .../org/apache/tajo/catalog/FunctionDesc.java   |  2 +-
 .../java/org/apache/tajo/catalog/Schema.java    |  6 +-
 .../org/apache/tajo/catalog/SchemaUtil.java     |  2 +-
 .../tajo/catalog/statistics/TableStats.java     |  4 +-
 .../tajo/catalog/statistics/TestTableStat.java  |  2 +-
 .../tajo/catalog/store/HiveCatalogStore.java    |  6 +-
 .../store/HiveCatalogStoreClientPool.java       |  2 +-
 .../catalog/store/TestHiveCatalogStore.java     |  2 +-
 .../org/apache/tajo/catalog/CatalogServer.java  |  5 +-
 .../tajo/catalog/LinkedMetadataManager.java     |  4 +-
 .../InfoSchemaMetadataDictionary.java           |  4 +-
 .../tajo/catalog/store/AbstractDBStore.java     | 22 +++----
 .../catalog/store/XMLCatalogSchemaManager.java  | 22 +++----
 .../tajo/catalog/store/object/BaseSchema.java   |  2 +-
 .../tajo/catalog/store/object/SchemaPatch.java  |  2 +-
 .../tajo/catalog/store/object/StoreObject.java  |  6 +-
 .../org/apache/tajo/catalog/TestCatalog.java    |  6 +-
 .../store/TestXMLCatalogSchemaManager.java      |  4 +-
 .../org/apache/tajo/cli/tools/TajoAdmin.java    | 10 +--
 .../org/apache/tajo/cli/tools/TajoDump.java     |  4 +-
 .../org/apache/tajo/cli/tsql/SimpleParser.java  |  6 +-
 .../java/org/apache/tajo/cli/tsql/TajoCli.java  |  2 +-
 .../cli/tsql/commands/DescFunctionCommand.java  |  4 +-
 .../tajo/cli/tsql/commands/SetCommand.java      |  2 +-
 .../apache/tajo/client/DummyServiceTracker.java |  2 +-
 .../apache/tajo/client/SessionConnection.java   |  2 +-
 .../org/apache/tajo/jdbc/MetaDataTuple.java     |  4 +-
 .../java/org/apache/tajo/QueryTestCaseBase.java |  8 +--
 .../org/apache/tajo/TajoTestingCluster.java     |  2 +-
 .../java/org/apache/tajo/QueryIdFactory.java    |  2 +-
 .../apache/tajo/exception/ErrorMessages.java    |  2 +-
 .../apache/tajo/rule/base/BaseRuleProvider.java |  2 +-
 .../tajo/util/datetime/DateTimeConstants.java   |  2 +-
 .../tajo/util/datetime/DateTimeFormat.java      |  4 +-
 .../tajo/util/graph/DirectedGraphCursor.java    |  2 +-
 .../tajo/util/graph/SimpleDirectedGraph.java    |  8 +--
 .../cli/tsql/TestDefaultCliOutputFormatter.java |  2 +-
 .../org/apache/tajo/client/TestTajoClient.java  |  4 +-
 .../tajo/engine/eval/TestEvalTreeUtil.java      |  2 +-
 .../tajo/engine/planner/TestLogicalPlan.java    |  4 +-
 .../tajo/engine/planner/TestLogicalPlanner.java |  2 +-
 .../tajo/engine/planner/TestPlannerUtil.java    |  2 +-
 .../planner/physical/TestHashPartitioner.java   |  2 +-
 .../planner/physical/TestPhysicalPlanner.java   |  4 +-
 .../planner/physical/TestTupleSorter.java       |  2 +-
 .../tajo/engine/query/TestGroupByQuery.java     |  6 +-
 .../tajo/engine/query/TestHBaseTable.java       | 14 ++--
 .../apache/tajo/engine/query/TestIndexScan.java |  2 +-
 .../apache/tajo/engine/query/TestJoinQuery.java |  2 +-
 .../tajo/engine/query/TestJsonWithTimezone.java |  2 +-
 .../tajo/engine/query/TestSelectQuery.java      |  2 +-
 .../tajo/engine/query/TestTablePartitions.java  |  2 +-
 .../apache/tajo/engine/util/TestTableCache.java |  2 +-
 .../apache/tajo/master/TestRepartitioner.java   | 26 ++++----
 .../master/scheduler/TestSimpleScheduler.java   |  4 +-
 .../tajo/querymaster/TestIntermediateEntry.java |  2 +-
 .../java/org/apache/tajo/util/TestJSPUtil.java  |  4 +-
 .../util/history/TestHistoryWriterReader.java   |  4 +-
 .../tajo/util/metrics/TestMetricsFilter.java    |  2 +-
 .../tajo/util/metrics/TestSystemMetrics.java    |  2 +-
 .../tajo/worker/MockNodeResourceManager.java    |  2 +-
 .../tajo/worker/TestNodeResourceManager.java    | 10 +--
 .../apache/tajo/worker/TestTaskExecutor.java    |  4 +-
 .../org/apache/tajo/worker/TestTaskManager.java |  2 +-
 .../ws/rs/resources/TestSessionsResource.java   |  6 +-
 .../org/apache/tajo/benchmark/BenchmarkSet.java |  6 +-
 .../engine/codegen/ExecutorPreCompiler.java     |  2 +-
 .../engine/codegen/TajoGeneratorAdapter.java    |  2 +-
 .../tajo/engine/function/FunctionLoader.java    |  2 +-
 .../tajo/engine/function/builtin/Lead.java      |  2 +-
 .../engine/planner/PhysicalPlannerImpl.java     |  2 +-
 .../engine/planner/global/ExecutionBlock.java   |  6 +-
 .../planner/global/ExecutionBlockCursor.java    | 12 ++--
 .../engine/planner/global/GlobalPlanner.java    |  2 +-
 .../tajo/engine/planner/global/MasterPlan.java  |  6 +-
 .../planner/global/ParallelExecutionQueue.java  | 10 +--
 .../global/builder/DistinctGroupbyBuilder.java  | 46 ++++++-------
 .../rewriter/GlobalPlanRewriteEngine.java       |  2 +-
 .../planner/physical/BSTIndexScanExec.java      |  2 +-
 .../planner/physical/CommonHashJoinExec.java    |  2 +-
 .../DistinctGroupbyFirstAggregationExec.java    |  6 +-
 .../DistinctGroupbyHashAggregationExec.java     |  8 +--
 .../DistinctGroupbySecondAggregationExec.java   |  8 +--
 .../DistinctGroupbyThirdAggregationExec.java    |  6 +-
 .../planner/physical/HashAggregateExec.java     |  2 +-
 .../HashBasedColPartitionStoreExec.java         |  4 +-
 .../planner/physical/HashFullOuterJoinExec.java |  2 +-
 .../physical/HashShuffleFileWriteExec.java      |  4 +-
 .../planner/physical/PhysicalPlanUtil.java      |  4 +-
 .../engine/planner/physical/SeqScanExec.java    |  2 +-
 .../apache/tajo/engine/query/QueryContext.java  |  2 +-
 .../tajo/engine/query/TaskRequestImpl.java      |  4 +-
 .../org/apache/tajo/ha/HdfsServiceTracker.java  |  2 +-
 .../org/apache/tajo/master/QueryInProgress.java |  6 +-
 .../org/apache/tajo/master/QueryManager.java    |  4 +-
 .../tajo/master/TajoMasterClientService.java    |  6 +-
 .../apache/tajo/master/exec/DDLExecutor.java    |  2 +-
 .../exec/ExplainPlanPreprocessorForTest.java    |  2 +-
 .../NonForwardQueryResultSystemScanner.java     | 24 +++----
 .../apache/tajo/master/exec/QueryExecutor.java  |  2 +-
 .../prehook/DistributedQueryHookManager.java    |  2 +-
 .../tajo/master/rule/MasterRuleProvider.java    |  2 +-
 .../tajo/master/scheduler/SimpleScheduler.java  |  6 +-
 .../tajo/metrics/ClusterResourceMetricSet.java  |  2 +-
 .../org/apache/tajo/parser/sql/SQLAnalyzer.java | 16 ++---
 .../tajo/querymaster/DefaultTaskScheduler.java  | 18 ++---
 .../java/org/apache/tajo/querymaster/Query.java |  8 +--
 .../apache/tajo/querymaster/QueryMaster.java    | 10 +--
 .../querymaster/QueryMasterManagerService.java  |  2 +-
 .../tajo/querymaster/QueryMasterTask.java       |  4 +-
 .../apache/tajo/querymaster/Repartitioner.java  | 69 ++++++++++----------
 .../java/org/apache/tajo/querymaster/Stage.java |  6 +-
 .../java/org/apache/tajo/querymaster/Task.java  | 26 ++++----
 .../apache/tajo/querymaster/TaskAttempt.java    |  4 +-
 .../java/org/apache/tajo/session/Session.java   |  4 +-
 .../org/apache/tajo/session/SessionManager.java |  2 +-
 .../main/java/org/apache/tajo/util/JSPUtil.java | 10 +--
 .../apache/tajo/util/history/HistoryReader.java |  4 +-
 .../apache/tajo/util/history/HistoryWriter.java |  8 +--
 .../apache/tajo/util/history/QueryHistory.java  |  4 +-
 .../apache/tajo/util/history/StageHistory.java  |  2 +-
 .../tajo/util/metrics/LogEventGaugeSet.java     |  2 +-
 .../tajo/util/metrics/MetricsFilterList.java    |  2 +-
 .../tajo/util/metrics/RegexpMetricsFilter.java  |  2 +-
 .../tajo/util/metrics/TajoSystemMetrics.java    |  8 +--
 .../metrics/reporter/TajoMetricsReporter.java   |  6 +-
 .../reporter/TajoMetricsScheduledReporter.java  |  2 +-
 .../java/org/apache/tajo/webapp/HttpServer.java |  6 +-
 .../tajo/webapp/QueryExecutorServlet.java       | 14 ++--
 .../tajo/worker/ExecutionBlockContext.java      |  8 +--
 .../worker/ExecutionBlockSharedResource.java    |  2 +-
 .../java/org/apache/tajo/worker/FetchImpl.java  |  4 +-
 .../apache/tajo/worker/NodeStatusUpdater.java   |  2 +-
 .../java/org/apache/tajo/worker/TajoWorker.java |  2 +-
 .../apache/tajo/worker/TaskAttemptContext.java  |  6 +-
 .../org/apache/tajo/worker/TaskExecutor.java    |  2 +-
 .../java/org/apache/tajo/worker/TaskImpl.java   |  4 +-
 .../org/apache/tajo/worker/TaskManager.java     |  2 +-
 .../tajo/worker/rule/WorkerRuleProvider.java    |  2 +-
 .../apache/tajo/ws/rs/ClientApplication.java    |  4 +-
 .../ws/rs/JerseyResourceDelegateContext.java    |  2 +-
 .../ws/rs/JerseyResourceDelegateContextKey.java |  4 +-
 .../tajo/ws/rs/resources/ClusterResource.java   |  4 +-
 .../tajo/ws/rs/resources/DatabasesResource.java |  2 +-
 .../tajo/ws/rs/resources/FunctionsResource.java |  4 +-
 .../tajo/ws/rs/resources/QueryResource.java     |  8 +--
 .../tajo/ws/rs/resources/SessionsResource.java  |  4 +-
 .../tajo/ws/rs/resources/TablesResource.java    |  2 +-
 .../main/resources/webapps/admin/cluster.jsp    | 12 ++--
 .../main/resources/webapps/admin/functions.jsp  |  2 +-
 .../src/main/resources/webapps/admin/query.jsp  |  6 +-
 .../main/resources/webapps/admin/querytasks.jsp |  4 +-
 .../main/resources/webapps/worker/queryplan.jsp |  4 +-
 .../resources/webapps/worker/querytasks.jsp     |  4 +-
 .../apache/tajo/jdbc/TajoDatabaseMetaData.java  | 12 ++--
 .../apache/tajo/jdbc/TajoPreparedStatement.java |  2 +-
 .../tajo/jdbc/util/QueryStringDecoder.java      |  4 +-
 .../tajo/jdbc/TestTajoDatabaseMetaData.java     |  6 +-
 .../java/org/apache/tajo/jdbc/TestTajoJdbc.java |  4 +-
 .../tajo/maven/plugin/protoc/ProtocMojo.java    |  8 +--
 .../org/apache/tajo/maven/plugin/util/Exec.java |  2 +-
 .../plugin/versioninfo/VersionInfoMojo.java     |  2 +-
 .../org/apache/tajo/plan/ExprAnnotator.java     |  4 +-
 .../org/apache/tajo/plan/ExprNormalizer.java    |  8 +--
 .../org/apache/tajo/plan/LogicalOptimizer.java  |  8 +--
 .../java/org/apache/tajo/plan/LogicalPlan.java  | 12 ++--
 .../org/apache/tajo/plan/LogicalPlanner.java    | 16 ++---
 .../java/org/apache/tajo/plan/PlanString.java   |  4 +-
 .../apache/tajo/plan/expr/AlgebraicUtil.java    |  6 +-
 .../org/apache/tajo/plan/expr/CaseWhenEval.java |  2 +-
 .../org/apache/tajo/plan/expr/EvalTreeUtil.java |  2 +-
 .../plan/exprrewrite/rules/ConstantFolding.java |  2 +-
 .../tajo/plan/joinorder/JoinGraphContext.java   |  4 +-
 .../tajo/plan/logical/DistinctGroupbyNode.java  |  4 +-
 .../org/apache/tajo/plan/logical/JoinSpec.java  |  2 +-
 .../tajo/plan/rewrite/BaseSchemaBuildPhase.java |  2 +-
 .../rewrite/rules/ProjectionPushDownRule.java   | 14 ++--
 .../org/apache/tajo/plan/util/PlannerUtil.java  |  4 +-
 .../plan/visitor/ExplainLogicalPlanVisitor.java |  4 +-
 .../tajo/pullserver/HttpDataServerHandler.java  |  4 +-
 .../tajo/pullserver/TajoPullServerService.java  |  6 +-
 .../retriever/AdvancedDataRetriever.java        |  2 +-
 .../java/org/apache/tajo/rpc/NettyUtils.java    |  2 +-
 .../org/apache/tajo/storage/DiskDeviceInfo.java |  2 +-
 .../java/org/apache/tajo/storage/DiskUtil.java  |  8 +--
 .../org/apache/tajo/storage/MergeScanner.java   |  2 +-
 .../apache/tajo/storage/OldStorageManager.java  |  4 +-
 .../apache/tajo/storage/compress/CodecPool.java |  4 +-
 .../tajo/storage/TestTupleComparator.java       |  4 +-
 .../storage/hbase/AbstractHBaseAppender.java    |  4 +-
 .../tajo/storage/hbase/ColumnMapping.java       |  2 +-
 .../tajo/storage/hbase/HBaseTablespace.java     | 28 ++++----
 .../tajo/storage/hbase/HFileAppender.java       |  2 +-
 .../storage/hbase/SortedInsertRewriter.java     |  2 +-
 .../org/apache/tajo/storage/FileTablespace.java | 14 ++--
 .../tajo/storage/HashShuffleAppender.java       |  8 +--
 .../storage/HashShuffleAppenderManager.java     |  8 +--
 .../apache/tajo/storage/avro/AvroAppender.java  |  4 +-
 .../apache/tajo/storage/avro/AvroScanner.java   |  4 +-
 .../tajo/storage/fragment/FileFragment.java     |  2 +-
 .../apache/tajo/storage/index/bst/BSTIndex.java |  4 +-
 .../org/apache/tajo/storage/orc/ORCScanner.java |  2 +-
 .../TajoStructObjectInspector.java              |  2 +-
 .../storage/parquet/TajoSchemaConverter.java    |  4 +-
 .../tajo/storage/parquet/TajoWriteSupport.java  |  2 +-
 .../storage/rcfile/ColumnProjectionUtils.java   |  4 +-
 .../tajo/storage/text/DelimitedTextFile.java    |  2 +-
 .../thirdparty/orc/FileOrcDataSource.java       |  2 +-
 .../thirdparty/orc/HdfsOrcDataSource.java       |  2 +-
 .../storage/thirdparty/orc/MemoryManager.java   |  2 +-
 .../tajo/storage/thirdparty/orc/OrcUtils.java   |  2 +-
 .../tajo/storage/thirdparty/orc/WriterImpl.java | 12 ++--
 .../thirdparty/parquet/CodecFactory.java        |  6 +-
 .../parquet/ColumnChunkPageWriteStore.java      |  6 +-
 .../thirdparty/parquet/ParquetFileWriter.java   | 12 ++--
 .../thirdparty/parquet/ParquetReader.java       |  4 +-
 .../thirdparty/parquet/ParquetWriter.java       | 24 +++----
 .../tajo/storage/parquet/TestReadWrite.java     |  2 +-
 .../storage/parquet/TestSchemaConverter.java    |  4 +-
 .../objectweb/asm/commons/AdviceAdapter.java    |  8 +--
 .../objectweb/asm/commons/AnalyzerAdapter.java  | 14 ++--
 .../objectweb/asm/commons/GeneratorAdapter.java |  2 +-
 .../asm/commons/JSRInlinerAdapter.java          | 10 +--
 .../tajo/org/objectweb/asm/commons/Method.java  |  2 +-
 .../asm/commons/SerialVersionUIDAdder.java      |  6 +-
 .../objectweb/asm/optimizer/JarOptimizer.java   |  4 +-
 .../objectweb/asm/optimizer/NameMapping.java    |  2 +-
 .../org/objectweb/asm/optimizer/Shrinker.java   |  6 +-
 .../org/objectweb/asm/tree/AnnotationNode.java  | 10 +--
 .../tajo/org/objectweb/asm/tree/ClassNode.java  | 14 ++--
 .../tajo/org/objectweb/asm/tree/FieldNode.java  |  6 +-
 .../tajo/org/objectweb/asm/tree/FrameNode.java  |  4 +-
 .../asm/tree/LookupSwitchInsnNode.java          |  4 +-
 .../tajo/org/objectweb/asm/tree/MethodNode.java | 16 ++---
 .../objectweb/asm/tree/TableSwitchInsnNode.java |  2 +-
 .../objectweb/asm/tree/analysis/Analyzer.java   | 10 +--
 .../org/objectweb/asm/tree/analysis/Frame.java  |  6 +-
 .../objectweb/asm/tree/analysis/SmallSet.java   |  8 +--
 .../asm/tree/analysis/SourceInterpreter.java    |  2 +-
 .../asm/tree/analysis/SourceValue.java          |  2 +-
 .../objectweb/asm/tree/analysis/Subroutine.java |  4 +-
 .../tajo/org/objectweb/asm/util/ASMifier.java   |  4 +-
 .../objectweb/asm/util/CheckClassAdapter.java   |  6 +-
 .../objectweb/asm/util/CheckMethodAdapter.java  |  6 +-
 .../tajo/org/objectweb/asm/util/Printer.java    |  2 +-
 .../tajo/org/objectweb/asm/util/Textifier.java  |  2 +-
 .../objectweb/asm/xml/ASMContentHandler.java    | 30 ++++-----
 .../org/objectweb/asm/xml/SAXCodeAdapter.java   |  2 +-
 251 files changed, 704 insertions(+), 703 deletions(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/CHANGES
----------------------------------------------------------------------
diff --git a/CHANGES b/CHANGES
index cfad5fe..5e929ab 100644
--- a/CHANGES
+++ b/CHANGES
@@ -669,6 +669,9 @@ Release 0.11.0 - unreleased
 
   SUB TASKS
 
+    TAJO-1844: Eliminate explicit diamond expressions. 
+    (Contributed by Dongkyu Hwangbo, committed by hyunsik)
+
     TAJO-1465: Add ORCFileAppender to write into ORCFile table. 
     (Contributed by Joyngyoung Park, committed by hyunsik)
 

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-client/src/main/java/org/apache/tajo/catalog/AbstractCatalogClient.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-client/src/main/java/org/apache/tajo/catalog/AbstractCatalogClient.java b/tajo-catalog/tajo-catalog-client/src/main/java/org/apache/tajo/catalog/AbstractCatalogClient.java
index 1dc7a71..7fb3bed 100644
--- a/tajo-catalog/tajo-catalog-client/src/main/java/org/apache/tajo/catalog/AbstractCatalogClient.java
+++ b/tajo-catalog/tajo-catalog-client/src/main/java/org/apache/tajo/catalog/AbstractCatalogClient.java
@@ -512,7 +512,7 @@ public abstract class AbstractCatalogClient implements CatalogService, Closeable
 
   @Override
   public final Collection<FunctionDesc> getFunctions() {
-    List<FunctionDesc> list = new ArrayList<FunctionDesc>();
+    List<FunctionDesc> list = new ArrayList<>();
 
     try {
       final BlockingInterface stub = getStub();

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/CatalogUtil.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/CatalogUtil.java b/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/CatalogUtil.java
index 4e52de1..321b8ba 100644
--- a/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/CatalogUtil.java
+++ b/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/CatalogUtil.java
@@ -234,7 +234,7 @@ public class CatalogUtil {
 
   public static Pair<String, String> separateQualifierAndName(String name) {
     Preconditions.checkArgument(isFQTableName(name), "Must be a qualified name.");
-    return new Pair<String, String>(extractQualifier(name), extractSimpleName(name));
+    return new Pair<>(extractQualifier(name), extractSimpleName(name));
   }
 
   /**
@@ -741,7 +741,7 @@ public class CatalogUtil {
     }
   }
 
-  public static final Set<String> RESERVED_KEYWORDS_SET = new HashSet<String>();
+  public static final Set<String> RESERVED_KEYWORDS_SET = new HashSet<>();
 
   static final String [] RESERVED_KEYWORDS = {
       "AS", "ALL", "AND", "ANY", "ASYMMETRIC", "ASC",
@@ -869,7 +869,7 @@ public class CatalogUtil {
       partitionKeyList.add(builder.build());
     }
 
-    pair = new Pair<List<PartitionKeyProto>, String>(partitionKeyList, sb.toString());
+    pair = new Pair<>(partitionKeyList, sb.toString());
     return pair;
   }
 

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/FunctionDesc.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/FunctionDesc.java b/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/FunctionDesc.java
index a2d4b75..5fa0c15 100644
--- a/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/FunctionDesc.java
+++ b/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/FunctionDesc.java
@@ -50,7 +50,7 @@ public class FunctionDesc implements ProtoObject<FunctionDescProto>, Cloneable,
       FunctionType funcType, DataType retType, @NotNull DataType [] params) {
     this.signature = new FunctionSignature(funcType, signature.toLowerCase(), retType, params);
     this.invocation = new FunctionInvocation();
-    this.invocation.setLegacy(new ClassBaseInvocationDesc<Function>(clazz));
+    this.invocation.setLegacy(new ClassBaseInvocationDesc<>(clazz));
     this.supplement = new FunctionSupplement();
   }
 

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/Schema.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/Schema.java b/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/Schema.java
index abd3bca..ae7d274 100644
--- a/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/Schema.java
+++ b/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/Schema.java
@@ -122,9 +122,9 @@ public class Schema implements ProtoObject<SchemaProto>, Cloneable, GsonObject {
   }
 
   private void init() {
-    this.fields = new ArrayList<Column>();
-    this.fieldsByQualifiedName = new HashMap<String, Integer>();
-    this.fieldsByName = new HashMap<String, List<Integer>>();
+    this.fields = new ArrayList<>();
+    this.fieldsByQualifiedName = new HashMap<>();
+    this.fieldsByName = new HashMap<>();
   }
 
   /**

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/SchemaUtil.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/SchemaUtil.java b/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/SchemaUtil.java
index 4a8e419..6af9e06 100644
--- a/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/SchemaUtil.java
+++ b/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/SchemaUtil.java
@@ -133,7 +133,7 @@ public class SchemaUtil {
 
   public static ImmutableMap<String, Type> buildTypeMap(Iterable<Column> schema, String [] targetPaths) {
 
-    HashMap<String, Type> builder = new HashMap<String, Type>();
+    HashMap<String, Type> builder = new HashMap<>();
     for (Column column : schema) {
 
       // Keep types which only belong to projected paths

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/statistics/TableStats.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/statistics/TableStats.java b/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/statistics/TableStats.java
index dd358ae..9ff1fba 100644
--- a/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/statistics/TableStats.java
+++ b/tajo-catalog/tajo-catalog-common/src/main/java/org/apache/tajo/catalog/statistics/TableStats.java
@@ -145,7 +145,7 @@ public class TableStats implements ProtoObject<TableStatsProto>, Cloneable, Gson
   }
 
   public void setColumnStats(List<ColumnStats> columnStatses) {
-    this.columnStatses = new ArrayList<ColumnStats>(columnStatses);
+    this.columnStatses = new ArrayList<>(columnStatses);
   }
 
   public void addColumnStat(ColumnStats columnStats) {
@@ -183,7 +183,7 @@ public class TableStats implements ProtoObject<TableStatsProto>, Cloneable, Gson
     stat.avgRows = avgRows != null ? avgRows : null;
     stat.readBytes = readBytes != null ? readBytes : null;
 
-    stat.columnStatses = new ArrayList<ColumnStats>(this.columnStatses);
+    stat.columnStatses = new ArrayList<>(this.columnStatses);
 
     return stat;
   }

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-common/src/test/java/org/apache/tajo/catalog/statistics/TestTableStat.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-common/src/test/java/org/apache/tajo/catalog/statistics/TestTableStat.java b/tajo-catalog/tajo-catalog-common/src/test/java/org/apache/tajo/catalog/statistics/TestTableStat.java
index b649dd7..0356416 100644
--- a/tajo-catalog/tajo-catalog-common/src/test/java/org/apache/tajo/catalog/statistics/TestTableStat.java
+++ b/tajo-catalog/tajo-catalog-common/src/test/java/org/apache/tajo/catalog/statistics/TestTableStat.java
@@ -89,7 +89,7 @@ public class TestTableStat {
   public void testGetProtoThreadSafe() throws Exception {
     final TableStats tableStats = new TableStats();
 
-    List<ColumnStats> columnStatsList = new ArrayList<ColumnStats>();
+    List<ColumnStats> columnStatsList = new ArrayList<>();
     for (int i = 0; i < 3; i++) {
       Column column = new Column("col_" + (i + 1), Type.TEXT);
       ColumnStats columnStats = new ColumnStats(column);

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-drivers/tajo-hive/src/main/java/org/apache/tajo/catalog/store/HiveCatalogStore.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-drivers/tajo-hive/src/main/java/org/apache/tajo/catalog/store/HiveCatalogStore.java b/tajo-catalog/tajo-catalog-drivers/tajo-hive/src/main/java/org/apache/tajo/catalog/store/HiveCatalogStore.java
index e2229ba..e4d53b2 100644
--- a/tajo-catalog/tajo-catalog-drivers/tajo-hive/src/main/java/org/apache/tajo/catalog/store/HiveCatalogStore.java
+++ b/tajo-catalog/tajo-catalog-drivers/tajo-hive/src/main/java/org/apache/tajo/catalog/store/HiveCatalogStore.java
@@ -426,7 +426,7 @@ public class HiveCatalogStore extends CatalogConstants implements CatalogStore {
       org.apache.hadoop.hive.metastore.api.Table table = new org.apache.hadoop.hive.metastore.api.Table();
       table.setDbName(databaseName);
       table.setTableName(tableName);
-      table.setParameters(new HashMap<String, String>(tableDesc.getMeta().getOptions().getAllKeyValus()));
+      table.setParameters(new HashMap<>(tableDesc.getMeta().getOptions().getAllKeyValus()));
       // TODO: set owner
       //table.setOwner();
 
@@ -454,7 +454,7 @@ public class HiveCatalogStore extends CatalogConstants implements CatalogStore {
 
       // set column information
       List<Column> columns = tableDesc.getSchema().getRootColumns();
-      ArrayList<FieldSchema> cols = new ArrayList<FieldSchema>(columns.size());
+      ArrayList<FieldSchema> cols = new ArrayList<>(columns.size());
 
       for (Column eachField : columns) {
         cols.add(new FieldSchema(eachField.getSimpleName(),
@@ -464,7 +464,7 @@ public class HiveCatalogStore extends CatalogConstants implements CatalogStore {
 
       // set partition keys
       if (tableDesc.hasPartition() && tableDesc.getPartitionMethod().getPartitionType().equals(PartitionType.COLUMN)) {
-        List<FieldSchema> partitionKeys = new ArrayList<FieldSchema>();
+        List<FieldSchema> partitionKeys = new ArrayList<>();
         for (Column eachPartitionKey : tableDesc.getPartitionMethod().getExpressionSchema().getRootColumns()) {
           partitionKeys.add(new FieldSchema(eachPartitionKey.getSimpleName(),
               HiveCatalogUtil.getHiveFieldType(eachPartitionKey.getDataType()), ""));

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-drivers/tajo-hive/src/main/java/org/apache/tajo/catalog/store/HiveCatalogStoreClientPool.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-drivers/tajo-hive/src/main/java/org/apache/tajo/catalog/store/HiveCatalogStoreClientPool.java b/tajo-catalog/tajo-catalog-drivers/tajo-hive/src/main/java/org/apache/tajo/catalog/store/HiveCatalogStoreClientPool.java
index 9053c56..bfde8cf 100644
--- a/tajo-catalog/tajo-catalog-drivers/tajo-hive/src/main/java/org/apache/tajo/catalog/store/HiveCatalogStoreClientPool.java
+++ b/tajo-catalog/tajo-catalog-drivers/tajo-hive/src/main/java/org/apache/tajo/catalog/store/HiveCatalogStoreClientPool.java
@@ -34,7 +34,7 @@ import java.util.concurrent.atomic.AtomicBoolean;
 public class HiveCatalogStoreClientPool {
   private static final Logger LOG = Logger.getLogger(HiveCatalogStoreClientPool.class);
   private final ConcurrentLinkedQueue<HiveCatalogStoreClient> clientPool =
-      new ConcurrentLinkedQueue<HiveCatalogStoreClient>();
+          new ConcurrentLinkedQueue<>();
   private AtomicBoolean poolClosed = new AtomicBoolean(false);
   private HiveConf hiveConf;
 

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-drivers/tajo-hive/src/test/java/org/apache/tajo/catalog/store/TestHiveCatalogStore.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-drivers/tajo-hive/src/test/java/org/apache/tajo/catalog/store/TestHiveCatalogStore.java b/tajo-catalog/tajo-catalog-drivers/tajo-hive/src/test/java/org/apache/tajo/catalog/store/TestHiveCatalogStore.java
index b3af179..3abcf8b 100644
--- a/tajo-catalog/tajo-catalog-drivers/tajo-hive/src/test/java/org/apache/tajo/catalog/store/TestHiveCatalogStore.java
+++ b/tajo-catalog/tajo-catalog-drivers/tajo-hive/src/test/java/org/apache/tajo/catalog/store/TestHiveCatalogStore.java
@@ -286,7 +286,7 @@ public class TestHiveCatalogStore {
     PartitionDesc partitionDesc = new PartitionDesc();
     partitionDesc.setPartitionName(partitionName);
 
-    List<PartitionKeyProto> partitionKeyList = new ArrayList<PartitionKeyProto>();
+    List<PartitionKeyProto> partitionKeyList = new ArrayList<>();
     String[] partitionNames = partitionName.split("/");
     for(int i = 0; i < partitionNames.length; i++) {
       String[] eachPartitionName = partitionNames[i].split("=");

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/CatalogServer.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/CatalogServer.java b/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/CatalogServer.java
index a60ddda..e027059 100644
--- a/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/CatalogServer.java
+++ b/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/CatalogServer.java
@@ -82,8 +82,7 @@ public class CatalogServer extends AbstractService {
   private final Lock wlock = lock.writeLock();
 
   private CatalogStore store;
-  private Map<String, List<FunctionDescProto>> functions = new ConcurrentHashMap<String,
-      List<FunctionDescProto>>();
+  private Map<String, List<FunctionDescProto>> functions = new ConcurrentHashMap<>();
 
   protected LinkedMetadataManager linkedMetadataManager;
   protected final InfoSchemaMetadataDictionary metaDictionary = new InfoSchemaMetadataDictionary();
@@ -100,7 +99,7 @@ public class CatalogServer extends AbstractService {
     super(CatalogServer.class.getName());
     this.handler = new CatalogProtocolHandler();
     this.linkedMetadataManager = new LinkedMetadataManager(Collections.EMPTY_LIST);
-    this.builtingFuncs = new ArrayList<FunctionDesc>();
+    this.builtingFuncs = new ArrayList<>();
   }
 
   public CatalogServer(Collection<MetadataProvider> metadataProviders, Collection<FunctionDesc> sqlFuncs)

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/LinkedMetadataManager.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/LinkedMetadataManager.java b/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/LinkedMetadataManager.java
index a4c718e..e6fd285 100644
--- a/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/LinkedMetadataManager.java
+++ b/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/LinkedMetadataManager.java
@@ -88,7 +88,7 @@ public class LinkedMetadataManager {
       return Optional.absent();
     } else {
       MetadataProvider found = filtered.iterator().next();
-      return Optional.of(new Pair<String, URI>(found.getTablespaceName(), found.getTablespaceUri()));
+      return Optional.of(new Pair<>(found.getTablespaceName(), found.getTablespaceUri()));
     }
   }
 
@@ -101,7 +101,7 @@ public class LinkedMetadataManager {
   public Collection<Pair<String, URI>> getTablespaces() {
     ImmutableList.Builder<Pair<String, URI>> builder = ImmutableList.builder();
     for (MetadataProvider p : providerMap.values()) {
-      builder.add(new Pair<String, URI>(p.getDatabaseName(), p.getTablespaceUri()));
+      builder.add(new Pair<>(p.getDatabaseName(), p.getTablespaceUri()));
     }
     return builder.build();
   }

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/dictionary/InfoSchemaMetadataDictionary.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/dictionary/InfoSchemaMetadataDictionary.java b/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/dictionary/InfoSchemaMetadataDictionary.java
index 17f84d8..2de9807 100644
--- a/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/dictionary/InfoSchemaMetadataDictionary.java
+++ b/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/dictionary/InfoSchemaMetadataDictionary.java
@@ -44,8 +44,8 @@ public class InfoSchemaMetadataDictionary {
     MAX_TABLE
   }
   
-  private List<TableDescriptor> schemaInfoTableDescriptors = new ArrayList<TableDescriptor>(
-      Collections.nCopies(DEFINED_TABLES.MAX_TABLE.ordinal(), (TableDescriptor)null));
+  private List<TableDescriptor> schemaInfoTableDescriptors = new ArrayList<>(
+          Collections.nCopies(DEFINED_TABLES.MAX_TABLE.ordinal(), (TableDescriptor) null));
   
   public InfoSchemaMetadataDictionary() {
     createSystemTableDescriptors();

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/AbstractDBStore.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/AbstractDBStore.java b/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/AbstractDBStore.java
index d46ab3c..5494d0a 100644
--- a/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/AbstractDBStore.java
+++ b/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/AbstractDBStore.java
@@ -428,7 +428,7 @@ public abstract class AbstractDBStore extends CatalogConstants implements Catalo
     PreparedStatement pstmt = null;
     ResultSet resultSet = null;
 
-    List<String> tablespaceNames = new ArrayList<String>();
+    List<String> tablespaceNames = new ArrayList<>();
 
     try {
       String sql = "SELECT SPACE_NAME FROM " + TB_SPACES;
@@ -679,7 +679,7 @@ public abstract class AbstractDBStore extends CatalogConstants implements Catalo
     PreparedStatement pstmt = null;
     ResultSet resultSet = null;
 
-    List<String> databaseNames = new ArrayList<String>();
+    List<String> databaseNames = new ArrayList<>();
 
     try {
       String sql = "SELECT DB_NAME FROM " + TB_DATABASES;
@@ -709,7 +709,7 @@ public abstract class AbstractDBStore extends CatalogConstants implements Catalo
     Statement stmt = null;
     ResultSet resultSet = null;
 
-    List<DatabaseProto> databases = new ArrayList<DatabaseProto>();
+    List<DatabaseProto> databases = new ArrayList<>();
 
     try {
       String sql = "SELECT DB_ID, DB_NAME, SPACE_ID FROM " + TB_DATABASES;
@@ -1814,7 +1814,7 @@ public abstract class AbstractDBStore extends CatalogConstants implements Catalo
     PreparedStatement pstmt = null;
     ResultSet res = null;
 
-    List<String> tables = new ArrayList<String>();
+    List<String> tables = new ArrayList<>();
 
     try {
 
@@ -1847,7 +1847,7 @@ public abstract class AbstractDBStore extends CatalogConstants implements Catalo
     Statement stmt = null;
     ResultSet resultSet = null;
 
-    List<TableDescriptorProto> tables = new ArrayList<TableDescriptorProto>();
+    List<TableDescriptorProto> tables = new ArrayList<>();
 
     try {
       String sql = "SELECT t.TID, t.DB_ID, t." + COL_TABLES_NAME + ", t.TABLE_TYPE, t.PATH, t.STORE_TYPE, " +
@@ -1896,7 +1896,7 @@ public abstract class AbstractDBStore extends CatalogConstants implements Catalo
     Statement stmt = null;
     ResultSet resultSet = null;
 
-    List<TableOptionProto> options = new ArrayList<TableOptionProto>();
+    List<TableOptionProto> options = new ArrayList<>();
 
     try {
       String sql = "SELECT tid, key_, value_ FROM " + TB_OPTIONS;
@@ -1931,7 +1931,7 @@ public abstract class AbstractDBStore extends CatalogConstants implements Catalo
     Statement stmt = null;
     ResultSet resultSet = null;
 
-    List<TableStatsProto> stats = new ArrayList<TableStatsProto>();
+    List<TableStatsProto> stats = new ArrayList<>();
 
     try {
       String sql = "SELECT tid, num_rows, num_bytes FROM " + TB_STATISTICS;
@@ -1963,7 +1963,7 @@ public abstract class AbstractDBStore extends CatalogConstants implements Catalo
     Statement stmt = null;
     ResultSet resultSet = null;
 
-    List<ColumnProto> columns = new ArrayList<ColumnProto>();
+    List<ColumnProto> columns = new ArrayList<>();
 
     try {
       String sql =
@@ -2198,7 +2198,7 @@ public abstract class AbstractDBStore extends CatalogConstants implements Catalo
     ResultSet res = null;
     PreparedStatement pstmt = null;
     PartitionDescProto.Builder builder = null;
-    List<PartitionDescProto> partitions = new ArrayList<PartitionDescProto>();
+    List<PartitionDescProto> partitions = new ArrayList<>();
 
     final int databaseId = getDatabaseId(databaseName);
     final int tableId = getTableId(databaseId, databaseName, tableName);
@@ -2238,7 +2238,7 @@ public abstract class AbstractDBStore extends CatalogConstants implements Catalo
     Statement stmt = null;
     ResultSet resultSet = null;
 
-    List<TablePartitionProto> partitions = new ArrayList<TablePartitionProto>();
+    List<TablePartitionProto> partitions = new ArrayList<>();
 
     try {
       String sql = "SELECT " + COL_PARTITIONS_PK + ", " + COL_TABLES_PK + ", PARTITION_NAME, " +
@@ -2731,7 +2731,7 @@ public abstract class AbstractDBStore extends CatalogConstants implements Catalo
 
     ResultSet res = null;
     PreparedStatement pstmt = null;
-    final List<String> indexNames = new ArrayList<String>();
+    final List<String> indexNames = new ArrayList<>();
 
     try {
       final int databaseId = getDatabaseId(databaseName);

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/XMLCatalogSchemaManager.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/XMLCatalogSchemaManager.java b/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/XMLCatalogSchemaManager.java
index 0ecd90a..65a8c5b 100644
--- a/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/XMLCatalogSchemaManager.java
+++ b/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/XMLCatalogSchemaManager.java
@@ -93,7 +93,7 @@ public class XMLCatalogSchemaManager {
       throw new TajoInternalError("Schema files are not loaded yet.");
     }
     
-    List<DatabaseObject> failedObjects = new ArrayList<DatabaseObject>();
+    List<DatabaseObject> failedObjects = new ArrayList<>();
     Statement stmt = null;
     
     try {
@@ -304,7 +304,7 @@ public class XMLCatalogSchemaManager {
       throw new TajoInternalError("Database schema files are not loaded.");
     }
     
-    final List<SchemaPatch> candidatePatches = new ArrayList<SchemaPatch>();
+    final List<SchemaPatch> candidatePatches = new ArrayList<>();
     Statement stmt;
     
     for (SchemaPatch patch: this.catalogStore.getPatches()) {
@@ -392,7 +392,7 @@ public class XMLCatalogSchemaManager {
       throws URISyntaxException, IOException {
     String[] files;
     String[] tempFiles;
-    List<String> filesList = new ArrayList<String>();
+    List<String> filesList = new ArrayList<>();
     File dirFile = new File(dirURL.toURI());
     
     tempFiles = dirFile.list(filter);
@@ -418,7 +418,7 @@ public class XMLCatalogSchemaManager {
 
     URL jarFileURL = new URL(spec.substring(0, seperator));
     JarFile jarFile = new JarFile(jarFileURL.toURI().getPath());
-    Set<String> filesSet = new HashSet<String>();
+    Set<String> filesSet = new HashSet<>();
     
     try {
       Enumeration<JarEntry> entries = jarFile.entries();
@@ -486,7 +486,7 @@ public class XMLCatalogSchemaManager {
   
   protected void loadFromXmlFiles() throws IOException, XMLStreamException, URISyntaxException {
     XMLInputFactory xmlIf = XMLInputFactory.newInstance();
-    final List<StoreObject> storeObjects = new ArrayList<StoreObject>();
+    final List<StoreObject> storeObjects = new ArrayList<>();
     
     xmlIf.setProperty(XMLInputFactory.IS_COALESCING, Boolean.TRUE);
     
@@ -545,7 +545,7 @@ public class XMLCatalogSchemaManager {
   
   private class StoreObjectsMerger {
     
-    private final List<StoreObject> storeObjects = new ArrayList<StoreObject>();
+    private final List<StoreObject> storeObjects = new ArrayList<>();
     private final StoreObject targetStore = new StoreObject();
     
     public StoreObjectsMerger(List<StoreObject> schemaObjects) {
@@ -579,7 +579,7 @@ public class XMLCatalogSchemaManager {
     private List<DatabaseObject> createListAndFillNull(int maxIdx) {
       DatabaseObject[] objects = new DatabaseObject[maxIdx];
       Arrays.fill(objects, null);
-      return new ArrayList<DatabaseObject>(Arrays.asList(objects));
+      return new ArrayList<>(Arrays.asList(objects));
     }
     
     protected List<DatabaseObject> mergeDatabaseObjects(List<DatabaseObject> objects) {
@@ -590,8 +590,8 @@ public class XMLCatalogSchemaManager {
       }
       
       final List<DatabaseObject> orderedObjects = createListAndFillNull(maxIdx);
-      final List<DatabaseObject> unorderedObjects = new ArrayList<DatabaseObject>();
-      final List<DatabaseObject> mergedObjects = new ArrayList<DatabaseObject>();
+      final List<DatabaseObject> unorderedObjects = new ArrayList<>();
+      final List<DatabaseObject> mergedObjects = new ArrayList<>();
       
       for (DatabaseObject object: objects) {
         if (object.getOrder() > -1) {
@@ -648,7 +648,7 @@ public class XMLCatalogSchemaManager {
     }
     
     protected void mergePatches(List<SchemaPatch> patches) {
-      final List<DatabaseObject> objects = new ArrayList<DatabaseObject>();
+      final List<DatabaseObject> objects = new ArrayList<>();
       
       Collections.sort(patches);
       
@@ -656,7 +656,7 @@ public class XMLCatalogSchemaManager {
         validatePatch(patches, patch);
         
         objects.clear();
-        List<DatabaseObject> tempObjects = new ArrayList<DatabaseObject>();
+        List<DatabaseObject> tempObjects = new ArrayList<>();
         tempObjects.addAll(patch.getObjects());
         patch.clearObjects();
         patch.addObjects(mergeDatabaseObjects(tempObjects));        

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/object/BaseSchema.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/object/BaseSchema.java b/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/object/BaseSchema.java
index 7c437af..eb715eb 100644
--- a/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/object/BaseSchema.java
+++ b/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/object/BaseSchema.java
@@ -37,7 +37,7 @@ public class BaseSchema implements Comparable<BaseSchema> {
   private String schemaName;
   @XmlElementWrapper(name="objects",namespace="http://tajo.apache.org/catalogstore")
   @XmlElement(name="Object",namespace="http://tajo.apache.org/catalogstore")
-  private final List<DatabaseObject> objects = new ArrayList<DatabaseObject>();
+  private final List<DatabaseObject> objects = new ArrayList<>();
   
   public int getVersion() {
     return version;

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/object/SchemaPatch.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/object/SchemaPatch.java b/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/object/SchemaPatch.java
index 6aa4500..ff825ae 100644
--- a/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/object/SchemaPatch.java
+++ b/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/object/SchemaPatch.java
@@ -36,7 +36,7 @@ public class SchemaPatch implements Comparable<SchemaPatch> {
   private int nextVersion;
   @XmlElementWrapper(name="objects",namespace="http://tajo.apache.org/catalogstore")
   @XmlElement(name="Object",namespace="http://tajo.apache.org/catalogstore")
-  private final List<DatabaseObject> objects = new ArrayList<DatabaseObject>();
+  private final List<DatabaseObject> objects = new ArrayList<>();
 
   public int getPriorVersion() {
     return priorVersion;

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/object/StoreObject.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/object/StoreObject.java b/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/object/StoreObject.java
index c83ee3b..f92af99 100644
--- a/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/object/StoreObject.java
+++ b/tajo-catalog/tajo-catalog-server/src/main/java/org/apache/tajo/catalog/store/object/StoreObject.java
@@ -34,13 +34,13 @@ public class StoreObject {
   private BaseSchema schema = new BaseSchema();
   @XmlElementWrapper(name="existQueries",namespace="http://tajo.apache.org/catalogstore")
   @XmlElement(name="existQuery",namespace="http://tajo.apache.org/catalogstore")
-  private final List<SQLObject> existQueries = new ArrayList<SQLObject>();
+  private final List<SQLObject> existQueries = new ArrayList<>();
   @XmlElementWrapper(name="dropStatements",namespace="http://tajo.apache.org/catalogstore")
   @XmlElement(name="dropStatement",namespace="http://tajo.apache.org/catalogstore")
-  private final List<SQLObject> dropStatements = new ArrayList<SQLObject>();
+  private final List<SQLObject> dropStatements = new ArrayList<>();
   @XmlElementWrapper(name="patches",namespace="http://tajo.apache.org/catalogstore")
   @XmlElement(name="patch",namespace="http://tajo.apache.org/catalogstore")
-  private final List<SchemaPatch> patches = new ArrayList<SchemaPatch>();
+  private final List<SchemaPatch> patches = new ArrayList<>();
   
   public BaseSchema getSchema() {
     return schema;

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-server/src/test/java/org/apache/tajo/catalog/TestCatalog.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-server/src/test/java/org/apache/tajo/catalog/TestCatalog.java b/tajo-catalog/tajo-catalog-server/src/test/java/org/apache/tajo/catalog/TestCatalog.java
index a5e4861..e4ad783 100644
--- a/tajo-catalog/tajo-catalog-server/src/test/java/org/apache/tajo/catalog/TestCatalog.java
+++ b/tajo-catalog/tajo-catalog-server/src/test/java/org/apache/tajo/catalog/TestCatalog.java
@@ -152,7 +152,7 @@ public class TestCatalog {
 
   @Test
   public void testCreateAndDropManyDatabases() throws Exception {
-    List<String> createdDatabases = new ArrayList<String>();
+    List<String> createdDatabases = new ArrayList<>();
     InfoSchemaMetadataDictionary dictionary = new InfoSchemaMetadataDictionary();
     String namePrefix = "database_";
     final int NUM = 10;
@@ -235,7 +235,7 @@ public class TestCatalog {
 
   private Map<String, List<String>> createBaseDatabaseAndTables() throws IOException, TajoException {
 
-    Map<String, List<String>> createdDatabaseAndTablesMap = new HashMap<String, List<String>>();
+    Map<String, List<String>> createdDatabaseAndTablesMap = new HashMap<>();
 
     // add and divide all tables to multiple databases in a round robin manner
     for (int tableId = 0; tableId < TOTAL_TABLE_NUM; tableId++) {
@@ -274,7 +274,7 @@ public class TestCatalog {
     Map<String, List<String>> createdTablesMap = createBaseDatabaseAndTables();
 
     // Each time we drop one database, check all databases and their tables.
-    Iterator<String> it = new ArrayList<String>(createdTablesMap.keySet()).iterator();
+    Iterator<String> it = new ArrayList<>(createdTablesMap.keySet()).iterator();
     while(it.hasNext()) {
       // drop one database
       String databaseName = it.next();

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-catalog/tajo-catalog-server/src/test/java/org/apache/tajo/catalog/store/TestXMLCatalogSchemaManager.java
----------------------------------------------------------------------
diff --git a/tajo-catalog/tajo-catalog-server/src/test/java/org/apache/tajo/catalog/store/TestXMLCatalogSchemaManager.java b/tajo-catalog/tajo-catalog-server/src/test/java/org/apache/tajo/catalog/store/TestXMLCatalogSchemaManager.java
index f53beff..a405426 100644
--- a/tajo-catalog/tajo-catalog-server/src/test/java/org/apache/tajo/catalog/store/TestXMLCatalogSchemaManager.java
+++ b/tajo-catalog/tajo-catalog-server/src/test/java/org/apache/tajo/catalog/store/TestXMLCatalogSchemaManager.java
@@ -152,7 +152,7 @@ public class TestXMLCatalogSchemaManager {
   }
   
   private <T> Matcher<Iterable<? extends T>> hasItem(Matcher<? extends T> matcher) {
-    return new CollectionMatcher<T>(matcher);
+    return new CollectionMatcher<>(matcher);
   }
   
   @BeforeClass
@@ -193,7 +193,7 @@ public class TestXMLCatalogSchemaManager {
   
   protected <T> BaseMatcher<T> hasItemInResultSet(final String expected, final String columnName) {
     return new BaseMatcher<T>() {
-      private final List<String> results = new ArrayList<String>();
+      private final List<String> results = new ArrayList<>();
 
       @Override
       public boolean matches(Object item) {

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-cli/src/main/java/org/apache/tajo/cli/tools/TajoAdmin.java
----------------------------------------------------------------------
diff --git a/tajo-cli/src/main/java/org/apache/tajo/cli/tools/TajoAdmin.java b/tajo-cli/src/main/java/org/apache/tajo/cli/tools/TajoAdmin.java
index 72f7f7a..d97b06f 100644
--- a/tajo-cli/src/main/java/org/apache/tajo/cli/tools/TajoAdmin.java
+++ b/tajo-cli/src/main/java/org/apache/tajo/cli/tools/TajoAdmin.java
@@ -226,12 +226,12 @@ public class TajoAdmin {
 
     int runningQueryMasterTasks = 0;
 
-    List<WorkerResourceInfo> liveWorkers = new ArrayList<WorkerResourceInfo>();
-    List<WorkerResourceInfo> deadWorkers = new ArrayList<WorkerResourceInfo>();
-    List<WorkerResourceInfo> decommissionWorkers = new ArrayList<WorkerResourceInfo>();
+    List<WorkerResourceInfo> liveWorkers = new ArrayList<>();
+    List<WorkerResourceInfo> deadWorkers = new ArrayList<>();
+    List<WorkerResourceInfo> decommissionWorkers = new ArrayList<>();
 
-    List<WorkerResourceInfo> liveQueryMasters = new ArrayList<WorkerResourceInfo>();
-    List<WorkerResourceInfo> deadQueryMasters = new ArrayList<WorkerResourceInfo>();
+    List<WorkerResourceInfo> liveQueryMasters = new ArrayList<>();
+    List<WorkerResourceInfo> deadQueryMasters = new ArrayList<>();
 
     for (WorkerResourceInfo eachWorker : workerList) {
       if(eachWorker.getWorkerStatus().equals(WorkerStatus.RUNNING.toString())) {

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-cli/src/main/java/org/apache/tajo/cli/tools/TajoDump.java
----------------------------------------------------------------------
diff --git a/tajo-cli/src/main/java/org/apache/tajo/cli/tools/TajoDump.java b/tajo-cli/src/main/java/org/apache/tajo/cli/tools/TajoDump.java
index a50ce7b..98b71a6 100644
--- a/tajo-cli/src/main/java/org/apache/tajo/cli/tools/TajoDump.java
+++ b/tajo-cli/src/main/java/org/apache/tajo/cli/tools/TajoDump.java
@@ -77,7 +77,7 @@ public class TajoDump {
         port = Integer.parseInt(conf.getVar(TajoConf.ConfVars.TAJO_MASTER_CLIENT_RPC_ADDRESS).split(":")[1]);
       }
     }
-    return new Pair<String, Integer>(hostName, port);
+    return new Pair<>(hostName, port);
   }
 
   public static void main(String [] args) throws ParseException, IOException, ServiceException, SQLException {
@@ -130,7 +130,7 @@ public class TajoDump {
 
     if (isDumpingAllDatabases) {
       // sort database names in an ascending lexicographic order of the names.
-      List<String> sorted = new ArrayList<String>(client.getAllDatabaseNames());
+      List<String> sorted = new ArrayList<>(client.getAllDatabaseNames());
       Collections.sort(sorted);
 
       for (String databaseName : sorted) {

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/SimpleParser.java
----------------------------------------------------------------------
diff --git a/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/SimpleParser.java b/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/SimpleParser.java
index 0cae7d4..2041e72 100644
--- a/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/SimpleParser.java
+++ b/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/SimpleParser.java
@@ -75,14 +75,14 @@ public class SimpleParser {
 
   public static List<ParsedResult> parseScript(String str) throws InvalidStatementException {
     SimpleParser parser = new SimpleParser();
-    List<ParsedResult> parsedResults = new ArrayList<ParsedResult>();
+    List<ParsedResult> parsedResults = new ArrayList<>();
     parsedResults.addAll(parser.parseLines(str));
     parsedResults.addAll(parser.EOF());
     return parsedResults;
   }
 
   public List<ParsedResult> parseLines(String str) throws InvalidStatementException {
-    List<ParsedResult> statements = new ArrayList<ParsedResult>();
+    List<ParsedResult> statements = new ArrayList<>();
     int lineStartIdx;
     int idx = 0;
     char [] chars = str.toCharArray();
@@ -330,7 +330,7 @@ public class SimpleParser {
    * @throws InvalidStatementException
    */
   private List<ParsedResult> doProcessEndOfStatement(boolean endOfFile) throws InvalidStatementException {
-    List<ParsedResult> parsedResults = new ArrayList<ParsedResult>();
+    List<ParsedResult> parsedResults = new ArrayList<>();
     String errorMessage = "";
     if (endOfFile) {
       if (state == ParsingState.META) {

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/TajoCli.java
----------------------------------------------------------------------
diff --git a/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/TajoCli.java b/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/TajoCli.java
index 8ae7075..3de9e7f 100644
--- a/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/TajoCli.java
+++ b/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/TajoCli.java
@@ -91,7 +91,7 @@ public class TajoCli {
       TajoGetConfCommand.class,
       TajoHAAdminCommand.class
   };
-  private final Map<String, TajoShellCommand> commands = new TreeMap<String, TajoShellCommand>();
+  private final Map<String, TajoShellCommand> commands = new TreeMap<>();
 
   protected static final Options options;
   private static final String HOME_DIR = System.getProperty("user.home");

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/commands/DescFunctionCommand.java
----------------------------------------------------------------------
diff --git a/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/commands/DescFunctionCommand.java b/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/commands/DescFunctionCommand.java
index abdbb9c..b168d3f 100644
--- a/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/commands/DescFunctionCommand.java
+++ b/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/commands/DescFunctionCommand.java
@@ -50,7 +50,7 @@ public class DescFunctionCommand extends TajoShellCommand {
     }
 
     List<CatalogProtos.FunctionDescProto> functions =
-        new ArrayList<CatalogProtos.FunctionDescProto>(client.getFunctions(functionName));
+            new ArrayList<>(client.getFunctions(functionName));
 
     Collections.sort(functions, new FunctionUtil.FunctionDescProtoComparator());
 
@@ -87,7 +87,7 @@ public class DescFunctionCommand extends TajoShellCommand {
 
     if (printDetail && !functions.isEmpty()) {
       Map<String, CatalogProtos.FunctionDescProto> functionMap =
-          new HashMap<String, CatalogProtos.FunctionDescProto>();
+              new HashMap<>();
 
       for (CatalogProtos.FunctionDescProto eachFunction: functions) {
         if (!functionMap.containsKey(eachFunction.getSupplement().getShortDescription())) {

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/commands/SetCommand.java
----------------------------------------------------------------------
diff --git a/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/commands/SetCommand.java b/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/commands/SetCommand.java
index 0ae07d5..b5802a5 100644
--- a/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/commands/SetCommand.java
+++ b/tajo-cli/src/main/java/org/apache/tajo/cli/tsql/commands/SetCommand.java
@@ -48,7 +48,7 @@ public class SetCommand extends TajoShellCommand {
   }
 
   private void updateSessionVariable(String key, String val) throws NoSuchSessionVariableException {
-    Map<String, String> variables = new HashMap<String, String>();
+    Map<String, String> variables = new HashMap<>();
     variables.put(key, val);
     client.updateSessionVariables(variables);
   }

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-client/src/main/java/org/apache/tajo/client/DummyServiceTracker.java
----------------------------------------------------------------------
diff --git a/tajo-client/src/main/java/org/apache/tajo/client/DummyServiceTracker.java b/tajo-client/src/main/java/org/apache/tajo/client/DummyServiceTracker.java
index fb2ba0c..ed15feb 100644
--- a/tajo-client/src/main/java/org/apache/tajo/client/DummyServiceTracker.java
+++ b/tajo-client/src/main/java/org/apache/tajo/client/DummyServiceTracker.java
@@ -79,7 +79,7 @@ public class DummyServiceTracker implements ServiceTracker {
 
   @Override
   public List<String> getMasters(TajoConf conf) throws ServiceTrackerException {
-    return new ArrayList<String>();
+    return new ArrayList<>();
   }
 
   @Override

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-client/src/main/java/org/apache/tajo/client/SessionConnection.java
----------------------------------------------------------------------
diff --git a/tajo-client/src/main/java/org/apache/tajo/client/SessionConnection.java b/tajo-client/src/main/java/org/apache/tajo/client/SessionConnection.java
index f63bb47..382d51b 100644
--- a/tajo-client/src/main/java/org/apache/tajo/client/SessionConnection.java
+++ b/tajo-client/src/main/java/org/apache/tajo/client/SessionConnection.java
@@ -73,7 +73,7 @@ public class SessionConnection implements Closeable {
   private final AtomicBoolean closed = new AtomicBoolean(false);
 
   /** session variable cache */
-  private final Map<String, String> sessionVarsCache = new HashMap<String, String>();
+  private final Map<String, String> sessionVarsCache = new HashMap<>();
 
   private final ServiceTracker serviceTracker;
 

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-client/src/main/java/org/apache/tajo/jdbc/MetaDataTuple.java
----------------------------------------------------------------------
diff --git a/tajo-client/src/main/java/org/apache/tajo/jdbc/MetaDataTuple.java b/tajo-client/src/main/java/org/apache/tajo/jdbc/MetaDataTuple.java
index bd078f6..e96bb44 100644
--- a/tajo-client/src/main/java/org/apache/tajo/jdbc/MetaDataTuple.java
+++ b/tajo-client/src/main/java/org/apache/tajo/jdbc/MetaDataTuple.java
@@ -32,10 +32,10 @@ import java.util.ArrayList;
 import java.util.List;
 
 public class MetaDataTuple implements Tuple {
-  List<Datum> values = new ArrayList<Datum>();
+  List<Datum> values = new ArrayList<>();
 
   public MetaDataTuple(int size) {
-    values = new ArrayList<Datum>(size);
+    values = new ArrayList<>(size);
     for(int i = 0; i < size; i++) {
       values.add(NullDatum.get());
     }

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-cluster-tests/src/test/java/org/apache/tajo/QueryTestCaseBase.java
----------------------------------------------------------------------
diff --git a/tajo-cluster-tests/src/test/java/org/apache/tajo/QueryTestCaseBase.java b/tajo-cluster-tests/src/test/java/org/apache/tajo/QueryTestCaseBase.java
index 2fde31c..ffa2dab 100644
--- a/tajo-cluster-tests/src/test/java/org/apache/tajo/QueryTestCaseBase.java
+++ b/tajo-cluster-tests/src/test/java/org/apache/tajo/QueryTestCaseBase.java
@@ -188,7 +188,7 @@ public class QueryTestCaseBase {
 
   /** It transiently contains created tables for the running test class. */
   private static String currentDatabase;
-  private static Set<String> createdTableGlobalSet = new HashSet<String>();
+  private static Set<String> createdTableGlobalSet = new HashSet<>();
   // queries and results directory corresponding to subclass class.
   protected Path currentQueryPath;
   protected Path namedQueryPath;
@@ -826,7 +826,7 @@ public class QueryTestCaseBase {
     }
     sb.append("\n-------------------------------\n");
 
-    List<String> results = new ArrayList<String>();
+    List<String> results = new ArrayList<>();
     while (resultSet.next()) {
       StringBuilder line = new StringBuilder();
       for (int i = 1; i <= numOfColumns; i++) {
@@ -982,7 +982,7 @@ public class QueryTestCaseBase {
     String compiled = compileTemplate(template, dataFilePath, args);
 
     List<ParsedResult> parsedResults = SimpleParser.parseScript(compiled);
-    List<String> createdTableNames = new ArrayList<String>();
+    List<String> createdTableNames = new ArrayList<>();
 
     for (ParsedResult parsedResult : parsedResults) {
       // parse a statement
@@ -1128,7 +1128,7 @@ public class QueryTestCaseBase {
   }
 
   private List<Path> listFiles(FileSystem fs, Path path) throws Exception {
-    List<Path> result = new ArrayList<Path>();
+    List<Path> result = new ArrayList<>();
     FileStatus[] files = fs.listStatus(path);
     if (files == null || files.length == 0) {
       return result;

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-cluster-tests/src/test/java/org/apache/tajo/TajoTestingCluster.java
----------------------------------------------------------------------
diff --git a/tajo-cluster-tests/src/test/java/org/apache/tajo/TajoTestingCluster.java b/tajo-cluster-tests/src/test/java/org/apache/tajo/TajoTestingCluster.java
index 8d2ee8f..3517cea 100644
--- a/tajo-cluster-tests/src/test/java/org/apache/tajo/TajoTestingCluster.java
+++ b/tajo-cluster-tests/src/test/java/org/apache/tajo/TajoTestingCluster.java
@@ -75,7 +75,7 @@ public class TajoTestingCluster {
   private HBaseTestClusterUtil hbaseUtil;
 
   private TajoMaster tajoMaster;
-  private List<TajoWorker> tajoWorkers = new ArrayList<TajoWorker>();
+  private List<TajoWorker> tajoWorkers = new ArrayList<>();
   private boolean isDFSRunning = false;
   private boolean isTajoClusterRunning = false;
   private boolean isCatalogServerRunning = false;

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-common/src/main/java/org/apache/tajo/QueryIdFactory.java
----------------------------------------------------------------------
diff --git a/tajo-common/src/main/java/org/apache/tajo/QueryIdFactory.java b/tajo-common/src/main/java/org/apache/tajo/QueryIdFactory.java
index 9599007..ae05f6b 100644
--- a/tajo-common/src/main/java/org/apache/tajo/QueryIdFactory.java
+++ b/tajo-common/src/main/java/org/apache/tajo/QueryIdFactory.java
@@ -36,7 +36,7 @@ public class QueryIdFactory {
 
   public static final  DecimalFormat ATTEMPT_ID_FORMAT = new DecimalFormat("00");
 
-  private static Map<String, AtomicInteger> queryNexIdMap = new HashMap<String, AtomicInteger>();
+  private static Map<String, AtomicInteger> queryNexIdMap = new HashMap<>();
 
   private static AtomicInteger nextId = new AtomicInteger(0);
 

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-common/src/main/java/org/apache/tajo/exception/ErrorMessages.java
----------------------------------------------------------------------
diff --git a/tajo-common/src/main/java/org/apache/tajo/exception/ErrorMessages.java b/tajo-common/src/main/java/org/apache/tajo/exception/ErrorMessages.java
index ed84aa7..368e4ae 100644
--- a/tajo-common/src/main/java/org/apache/tajo/exception/ErrorMessages.java
+++ b/tajo-common/src/main/java/org/apache/tajo/exception/ErrorMessages.java
@@ -128,7 +128,7 @@ public class ErrorMessages {
   }
 
   private static void ADD_MESSAGE(ResultCode code, String msgFormat, int argNum) {
-    MESSAGES.put(code, new Pair<String, Integer>(msgFormat, argNum));
+    MESSAGES.put(code, new Pair<>(msgFormat, argNum));
   }
 
   public static String getInternalErrorMessage() {

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-common/src/main/java/org/apache/tajo/rule/base/BaseRuleProvider.java
----------------------------------------------------------------------
diff --git a/tajo-common/src/main/java/org/apache/tajo/rule/base/BaseRuleProvider.java b/tajo-common/src/main/java/org/apache/tajo/rule/base/BaseRuleProvider.java
index 2a8eed8..7be2eeb 100644
--- a/tajo-common/src/main/java/org/apache/tajo/rule/base/BaseRuleProvider.java
+++ b/tajo-common/src/main/java/org/apache/tajo/rule/base/BaseRuleProvider.java
@@ -37,7 +37,7 @@ public class BaseRuleProvider implements SelfDiagnosisRuleProvider {
   public List<SelfDiagnosisRule> getDefinedRules() {
     Set<Class> classSet = ClassUtil.findClasses(SelfDiagnosisRule.class, 
         getClass().getPackage().getName());
-    List<SelfDiagnosisRule> ruleList = new ArrayList<SelfDiagnosisRule>(classSet.size());
+    List<SelfDiagnosisRule> ruleList = new ArrayList<>(classSet.size());
     
     for (Class<SelfDiagnosisRule> ruleClazz: classSet) {
       try {

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-common/src/main/java/org/apache/tajo/util/datetime/DateTimeConstants.java
----------------------------------------------------------------------
diff --git a/tajo-common/src/main/java/org/apache/tajo/util/datetime/DateTimeConstants.java b/tajo-common/src/main/java/org/apache/tajo/util/datetime/DateTimeConstants.java
index 1f77f43..e610dee 100644
--- a/tajo-common/src/main/java/org/apache/tajo/util/datetime/DateTimeConstants.java
+++ b/tajo-common/src/main/java/org/apache/tajo/util/datetime/DateTimeConstants.java
@@ -610,7 +610,7 @@ public class DateTimeConstants {
       return valueType;
     }
   }
-  public static final Map<String, DateToken> dateTokenMap = new HashMap<String, DateToken>();
+  public static final Map<String, DateToken> dateTokenMap = new HashMap<>();
 
   static {
     for (Object[] eachToken: datetktbl) {

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-common/src/main/java/org/apache/tajo/util/datetime/DateTimeFormat.java
----------------------------------------------------------------------
diff --git a/tajo-common/src/main/java/org/apache/tajo/util/datetime/DateTimeFormat.java b/tajo-common/src/main/java/org/apache/tajo/util/datetime/DateTimeFormat.java
index 798b9c5..19ad065 100644
--- a/tajo-common/src/main/java/org/apache/tajo/util/datetime/DateTimeFormat.java
+++ b/tajo-common/src/main/java/org/apache/tajo/util/datetime/DateTimeFormat.java
@@ -469,7 +469,7 @@ public class DateTimeFormat {
 
   static final KeyWord[] DCH_keywords = new KeyWord[DCH_keywordValues.length];
 
-  static Map<Character, Integer> DCH_index = new HashMap<Character, Integer>();
+  static Map<Character, Integer> DCH_index = new HashMap<>();
 
   static {
     int index = 0;
@@ -546,7 +546,7 @@ public class DateTimeFormat {
     int yysz;			/* is it YY or YYYY ? */
     int clock;		/* 12 or 24 hour clock? */
   }
-  static Map<String, FormatNode[]> formatNodeCache = new HashMap<String, FormatNode[]>();
+  static Map<String, FormatNode[]> formatNodeCache = new HashMap<>();
 
  /**
   * ----------

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-common/src/main/java/org/apache/tajo/util/graph/DirectedGraphCursor.java
----------------------------------------------------------------------
diff --git a/tajo-common/src/main/java/org/apache/tajo/util/graph/DirectedGraphCursor.java b/tajo-common/src/main/java/org/apache/tajo/util/graph/DirectedGraphCursor.java
index 9b15cfe..7d25dc8 100644
--- a/tajo-common/src/main/java/org/apache/tajo/util/graph/DirectedGraphCursor.java
+++ b/tajo-common/src/main/java/org/apache/tajo/util/graph/DirectedGraphCursor.java
@@ -22,7 +22,7 @@ import java.util.ArrayList;
 
 public class DirectedGraphCursor<V,E> {
   private DirectedGraph<V,E> graph;
-  private ArrayList<V> orderedVertices = new ArrayList<V>();
+  private ArrayList<V> orderedVertices = new ArrayList<>();
   private int cursor = 0;
 
   public DirectedGraphCursor(DirectedGraph<V, E> graph, V startVertex) {

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-common/src/main/java/org/apache/tajo/util/graph/SimpleDirectedGraph.java
----------------------------------------------------------------------
diff --git a/tajo-common/src/main/java/org/apache/tajo/util/graph/SimpleDirectedGraph.java b/tajo-common/src/main/java/org/apache/tajo/util/graph/SimpleDirectedGraph.java
index 045add5..d3a3a1e 100644
--- a/tajo-common/src/main/java/org/apache/tajo/util/graph/SimpleDirectedGraph.java
+++ b/tajo-common/src/main/java/org/apache/tajo/util/graph/SimpleDirectedGraph.java
@@ -153,7 +153,7 @@ public class SimpleDirectedGraph<V, E> implements DirectedGraph<V,E> {
 
   @Override
   public List<V> getChilds(V v) {
-    List<V> childBlocks = new ArrayList<V>();
+    List<V> childBlocks = new ArrayList<>();
     if (reversedEdges.containsKey(v)) {
       for (Map.Entry<V, E> entry: reversedEdges.get(v).entrySet()) {
         childBlocks.add(entry.getKey());
@@ -190,7 +190,7 @@ public class SimpleDirectedGraph<V, E> implements DirectedGraph<V,E> {
 
   @Override
   public List<V> getParents(V block) {
-    List<V> childBlocks = new ArrayList<V>();
+    List<V> childBlocks = new ArrayList<>();
     if (directedEdges.containsKey(block)) {
       for (Map.Entry<V, E> entry: directedEdges.get(block).entrySet()) {
         childBlocks.add(entry.getKey());
@@ -220,7 +220,7 @@ public class SimpleDirectedGraph<V, E> implements DirectedGraph<V,E> {
 
   @Override
   public void accept(V source, DirectedGraphVisitor<V> visitor) {
-    Stack<V> stack = new Stack<V>();
+    Stack<V> stack = new Stack<>();
     visitRecursive(stack, source, visitor);
   }
 
@@ -267,7 +267,7 @@ public class SimpleDirectedGraph<V, E> implements DirectedGraph<V,E> {
   }
 
   private class QueryGraphTopologyStringBuilder implements DirectedGraphVisitor<V> {
-    Stack<DepthString> depthString = new Stack<DepthString>();
+    Stack<DepthString> depthString = new Stack<>();
 
     @Override
     public void visit(Stack<V> stack, V vertex) {

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-core-tests/src/test/java/org/apache/tajo/cli/tsql/TestDefaultCliOutputFormatter.java
----------------------------------------------------------------------
diff --git a/tajo-core-tests/src/test/java/org/apache/tajo/cli/tsql/TestDefaultCliOutputFormatter.java b/tajo-core-tests/src/test/java/org/apache/tajo/cli/tsql/TestDefaultCliOutputFormatter.java
index cdcdb67..c497d74 100644
--- a/tajo-core-tests/src/test/java/org/apache/tajo/cli/tsql/TestDefaultCliOutputFormatter.java
+++ b/tajo-core-tests/src/test/java/org/apache/tajo/cli/tsql/TestDefaultCliOutputFormatter.java
@@ -144,7 +144,7 @@ public class TestDefaultCliOutputFormatter {
     stats.setNumRows(numRows);
     tableDesc.setStats(stats);
 
-    final List<MetaDataTuple> resultTables = new ArrayList<MetaDataTuple>();
+    final List<MetaDataTuple> resultTables = new ArrayList<>();
 
     String expectedOutput = "col1,  col2,  col3\n";
     expectedOutput += "-------------------------------\n";

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-core-tests/src/test/java/org/apache/tajo/client/TestTajoClient.java
----------------------------------------------------------------------
diff --git a/tajo-core-tests/src/test/java/org/apache/tajo/client/TestTajoClient.java b/tajo-core-tests/src/test/java/org/apache/tajo/client/TestTajoClient.java
index 60f04db..279e0a4 100644
--- a/tajo-core-tests/src/test/java/org/apache/tajo/client/TestTajoClient.java
+++ b/tajo-core-tests/src/test/java/org/apache/tajo/client/TestTajoClient.java
@@ -694,7 +694,7 @@ public class TestTajoClient {
           "  c_custkey,\n" +
           "  orders.o_orderkey;\n";
 
-    Map<String, String> variables = new HashMap<String, String>();
+    Map<String, String> variables = new HashMap<>();
     variables.put(SessionVars.NULL_CHAR.keyname(), "\\\\T");
     client.updateSessionVariables(variables);
     ResultSet res = client.executeQueryAndGetResult(sql);
@@ -763,7 +763,7 @@ public class TestTajoClient {
     assertEquals(2, queryHistory.getStageHistoriesCount());
 
     List<ClientProtos.StageHistoryProto> taskHistories =
-        new ArrayList<StageHistoryProto>(queryHistory.getStageHistoriesList());
+            new ArrayList<>(queryHistory.getStageHistoriesList());
     Collections.sort(taskHistories, new Comparator<StageHistoryProto>() {
       @Override
       public int compare(ClientProtos.StageHistoryProto o1, StageHistoryProto o2) {

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-core-tests/src/test/java/org/apache/tajo/engine/eval/TestEvalTreeUtil.java
----------------------------------------------------------------------
diff --git a/tajo-core-tests/src/test/java/org/apache/tajo/engine/eval/TestEvalTreeUtil.java b/tajo-core-tests/src/test/java/org/apache/tajo/engine/eval/TestEvalTreeUtil.java
index fd8e502..7bba76b 100644
--- a/tajo-core-tests/src/test/java/org/apache/tajo/engine/eval/TestEvalTreeUtil.java
+++ b/tajo-core-tests/src/test/java/org/apache/tajo/engine/eval/TestEvalTreeUtil.java
@@ -347,7 +347,7 @@ public class TestEvalTreeUtil {
     GroupbyNode groupByNode = plan.getRootBlock().getNode(NodeType.GROUP_BY);
     EvalNode [] aggEvals = groupByNode.getAggFunctions();
 
-    List<AggregationFunctionCallEval> list = new ArrayList<AggregationFunctionCallEval>();
+    List<AggregationFunctionCallEval> list = new ArrayList<>();
     for (int i = 0; i < aggEvals.length; i++) {
       list.addAll(EvalTreeUtil.findDistinctAggFunction(aggEvals[i]));
     }

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/TestLogicalPlan.java
----------------------------------------------------------------------
diff --git a/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/TestLogicalPlan.java b/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/TestLogicalPlan.java
index a03ee49..24feee0 100644
--- a/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/TestLogicalPlan.java
+++ b/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/TestLogicalPlan.java
@@ -73,11 +73,11 @@ public class TestLogicalPlan {
     assertTrue(graph.isLeaf(new1.getName()));
     assertTrue(graph.isLeaf(new2.getName()));
 
-    Set<LogicalPlan.QueryBlock> result = new HashSet<LogicalPlan.QueryBlock>();
+    Set<LogicalPlan.QueryBlock> result = new HashSet<>();
     result.add(new1);
     result.add(new2);
 
-    Set<LogicalPlan.QueryBlock> childs = new HashSet<LogicalPlan.QueryBlock>(plan.getChildBlocks(root));
+    Set<LogicalPlan.QueryBlock> childs = new HashSet<>(plan.getChildBlocks(root));
     assertEquals(result, childs);
 
     assertEquals(root, plan.getParentBlock(new1));

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/TestLogicalPlanner.java
----------------------------------------------------------------------
diff --git a/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/TestLogicalPlanner.java b/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/TestLogicalPlanner.java
index 38d02aa..e9220c3 100644
--- a/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/TestLogicalPlanner.java
+++ b/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/TestLogicalPlanner.java
@@ -865,7 +865,7 @@ public class TestLogicalPlanner {
   }
 
   private static class TestVisitor implements LogicalNodeVisitor {
-    Stack<LogicalNode> stack = new Stack<LogicalNode>();
+    Stack<LogicalNode> stack = new Stack<>();
     @Override
     public void visit(LogicalNode node) {
       stack.push(node);

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/TestPlannerUtil.java
----------------------------------------------------------------------
diff --git a/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/TestPlannerUtil.java b/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/TestPlannerUtil.java
index 5d02a7f..c9e0c46 100644
--- a/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/TestPlannerUtil.java
+++ b/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/TestPlannerUtil.java
@@ -342,7 +342,7 @@ public class TestPlannerUtil {
 
     FileSystem fs = path.getFileSystem(util.getConfiguration());
 
-    List<Path> expectedFiles = new ArrayList<Path>();
+    List<Path> expectedFiles = new ArrayList<>();
     RemoteIterator<LocatedFileStatus> files = fs.listFiles(path, true);
     while (files.hasNext()) {
       LocatedFileStatus file = files.next();

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/physical/TestHashPartitioner.java
----------------------------------------------------------------------
diff --git a/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/physical/TestHashPartitioner.java b/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/physical/TestHashPartitioner.java
index 1146e85..9558b2d 100644
--- a/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/physical/TestHashPartitioner.java
+++ b/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/physical/TestHashPartitioner.java
@@ -102,7 +102,7 @@ public class TestHashPartitioner {
     for (int index = 0; index <  testNumPartitions.length; index++) {
       Partitioner p = new HashPartitioner(new int[]{0, 1, 2}, testNumPartitions[index]);
 
-      Set<Integer> ids = new TreeSet<Integer>();
+      Set<Integer> ids = new TreeSet<>();
       for (int i = 0; i < data.length; i++) {
         Tuple tuple = new VTuple(
             new Datum[]{new TextDatum(data[i][0]), new TextDatum(data[i][1]), new TextDatum(data[i][2])});

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/physical/TestPhysicalPlanner.java
----------------------------------------------------------------------
diff --git a/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/physical/TestPhysicalPlanner.java b/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/physical/TestPhysicalPlanner.java
index 0b94c52..8bc619c 100644
--- a/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/physical/TestPhysicalPlanner.java
+++ b/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/physical/TestPhysicalPlanner.java
@@ -662,7 +662,7 @@ public class TestPhysicalPlanner {
     Path queryLocalTmpDir = new Path(conf.getVar(ConfVars.WORKER_TEMPORAL_DIR) + "/" + executionBlockBaseDir);
     FileStatus [] list = fs.listStatus(queryLocalTmpDir);
 
-    List<Fragment> fragments = new ArrayList<Fragment>();
+    List<Fragment> fragments = new ArrayList<>();
     for (FileStatus status : list) {
       assertTrue(status.isDirectory());
       FileStatus [] files = fs.listStatus(status.getPath());
@@ -796,7 +796,7 @@ public class TestPhysicalPlanner {
     Path queryLocalTmpDir = new Path(conf.getVar(ConfVars.WORKER_TEMPORAL_DIR) + "/" + executionBlockBaseDir);
     FileStatus [] list = fs.listStatus(queryLocalTmpDir);
 
-    List<Fragment> fragments = new ArrayList<Fragment>();
+    List<Fragment> fragments = new ArrayList<>();
     for (FileStatus status : list) {
       assertTrue(status.isDirectory());
       FileStatus [] files = fs.listStatus(status.getPath());

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/physical/TestTupleSorter.java
----------------------------------------------------------------------
diff --git a/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/physical/TestTupleSorter.java b/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/physical/TestTupleSorter.java
index 753eebc..2f7330b 100644
--- a/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/physical/TestTupleSorter.java
+++ b/tajo-core-tests/src/test/java/org/apache/tajo/engine/planner/physical/TestTupleSorter.java
@@ -76,7 +76,7 @@ public class TestTupleSorter {
     for(int iteration = 0; iteration < ITERATION; iteration++) {
       TupleList target = new TupleList(tuples.length);
       target.addAll(Arrays.asList(Arrays.copyOf(tuples, tuples.length)));
-      Set<Integer> keys = new TreeSet<Integer>();
+      Set<Integer> keys = new TreeSet<>();
       for (int i = 0; i < MAX_SORT_KEY; i++) {
         keys.add(rnd.nextInt(schema.size()));
       }

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestGroupByQuery.java
----------------------------------------------------------------------
diff --git a/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestGroupByQuery.java b/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestGroupByQuery.java
index 0fe5e0e..dd321ae 100644
--- a/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestGroupByQuery.java
+++ b/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestGroupByQuery.java
@@ -49,7 +49,7 @@ public class TestGroupByQuery extends QueryTestCaseBase {
   public TestGroupByQuery(String groupByOption) throws Exception {
     super(TajoConstants.DEFAULT_DATABASE_NAME);
 
-    Map<String, String> variables = new HashMap<String, String>();
+    Map<String, String> variables = new HashMap<>();
     if (groupByOption.equals("MultiLevel")) {
       variables.put(SessionVars.GROUPBY_MULTI_LEVEL_ENABLED.keyname(), "true");
     } else {
@@ -698,14 +698,14 @@ public class TestGroupByQuery extends QueryTestCaseBase {
     schema.addColumn("col1", Type.TEXT);
     schema.addColumn("col2", Type.TEXT);
 
-    List<String> data = new ArrayList<String>();
+    List<String> data = new ArrayList<>();
     int totalBytes = 0;
     Random rand = new Random(System.currentTimeMillis());
     String col1Prefix = "Column-1Column-1Column-1Column-1Column-1Column-1Column-1Column-1Column-1Column-1Column-1" +
         "Column-1Column-1Column-1Column-1Column-1Column-1Column-1Column-1Column-1Column-1Column-1" +
         "Column-1Column-1Column-1Column-1Column-1Column-1Column-1Column-1Column-1Column-1Column-1";
 
-    Set<Integer> uniqKeys = new HashSet<Integer>();
+    Set<Integer> uniqKeys = new HashSet<>();
     while(true) {
       int col1RandomValue = rand.nextInt(1000000);
       uniqKeys.add(col1RandomValue);

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestHBaseTable.java
----------------------------------------------------------------------
diff --git a/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestHBaseTable.java b/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestHBaseTable.java
index 59cb3ec..0d9c49b 100644
--- a/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestHBaseTable.java
+++ b/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestHBaseTable.java
@@ -789,7 +789,7 @@ public class TestHBaseTable extends QueryTestCaseBase {
     Schema schema = new Schema();
     schema.addColumn("id", Type.TEXT);
     schema.addColumn("name", Type.TEXT);
-    List<String> datas = new ArrayList<String>();
+    List<String> datas = new ArrayList<>();
     DecimalFormat df = new DecimalFormat("000");
     for (int i = 99; i >= 0; i--) {
       datas.add(df.format(i) + "|value" + i);
@@ -845,7 +845,7 @@ public class TestHBaseTable extends QueryTestCaseBase {
     Schema schema = new Schema();
     schema.addColumn("id", Type.TEXT);
     schema.addColumn("name", Type.TEXT);
-    List<String> datas = new ArrayList<String>();
+    List<String> datas = new ArrayList<>();
     for (int i = 99; i >= 0; i--) {
       datas.add(i + "|value" + i);
     }
@@ -903,7 +903,7 @@ public class TestHBaseTable extends QueryTestCaseBase {
     Schema schema = new Schema();
     schema.addColumn("id", Type.TEXT);
     schema.addColumn("name", Type.TEXT);
-    List<String> datas = new ArrayList<String>();
+    List<String> datas = new ArrayList<>();
     DecimalFormat df = new DecimalFormat("000");
     for (int i = 99; i >= 0; i--) {
       datas.add(df.format(i) + "|value" + i);
@@ -963,7 +963,7 @@ public class TestHBaseTable extends QueryTestCaseBase {
     schema.addColumn("id2", Type.TEXT);
     schema.addColumn("name", Type.TEXT);
     DecimalFormat df = new DecimalFormat("000");
-    List<String> datas = new ArrayList<String>();
+    List<String> datas = new ArrayList<>();
     for (int i = 99; i >= 0; i--) {
       datas.add(df.format(i) + "|" + (i + 100) + "|value" + i);
     }
@@ -1018,7 +1018,7 @@ public class TestHBaseTable extends QueryTestCaseBase {
     Schema schema = new Schema();
     schema.addColumn("id", Type.INT4);
     schema.addColumn("name", Type.TEXT);
-    List<String> datas = new ArrayList<String>();
+    List<String> datas = new ArrayList<>();
     for (int i = 99; i >= 0; i--) {
       datas.add(i + "|value" + i);
     }
@@ -1076,7 +1076,7 @@ public class TestHBaseTable extends QueryTestCaseBase {
     schema.addColumn("col2_key", Type.TEXT);
     schema.addColumn("col2_value", Type.TEXT);
     schema.addColumn("col3", Type.TEXT);
-    List<String> datas = new ArrayList<String>();
+    List<String> datas = new ArrayList<>();
     for (int i = 20; i >= 0; i--) {
       for (int j = 0; j < 3; j++) {
         datas.add(i + "|ck-" + j + "|value-" + j + "|col3-" + i);
@@ -1163,7 +1163,7 @@ public class TestHBaseTable extends QueryTestCaseBase {
     Schema schema = new Schema();
     schema.addColumn("id", Type.INT4);
     schema.addColumn("name", Type.TEXT);
-    List<String> datas = new ArrayList<String>();
+    List<String> datas = new ArrayList<>();
     for (int i = 99; i >= 0; i--) {
       datas.add(i + "|value" + i);
     }

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestIndexScan.java
----------------------------------------------------------------------
diff --git a/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestIndexScan.java b/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestIndexScan.java
index a255c6d..19b1486 100644
--- a/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestIndexScan.java
+++ b/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestIndexScan.java
@@ -37,7 +37,7 @@ public class TestIndexScan extends QueryTestCaseBase {
 
   public TestIndexScan() throws ServiceException, SQLException, NoSuchSessionVariableException {
     super(TajoConstants.DEFAULT_DATABASE_NAME);
-    Map<String,String> sessionVars = new HashMap<String, String>();
+    Map<String,String> sessionVars = new HashMap<>();
     sessionVars.put(SessionVars.INDEX_ENABLED.keyname(), "true");
     sessionVars.put(SessionVars.INDEX_SELECTIVITY_THRESHOLD.keyname(), "0.01f");
     client.updateSessionVariables(sessionVars);

http://git-wip-us.apache.org/repos/asf/tajo/blob/aa699c70/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestJoinQuery.java
----------------------------------------------------------------------
diff --git a/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestJoinQuery.java b/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestJoinQuery.java
index 90a004b..2372a11 100644
--- a/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestJoinQuery.java
+++ b/tajo-core-tests/src/test/java/org/apache/tajo/engine/query/TestJoinQuery.java
@@ -296,7 +296,7 @@ public class TestJoinQuery extends QueryTestCaseBase {
 
   protected static List<Path> getPartitionPathList(FileSystem fs, Path path) throws Exception {
     FileStatus[] files = fs.listStatus(path);
-    List<Path> paths = new ArrayList<Path>();
+    List<Path> paths = new ArrayList<>();
     if (files != null) {
       for (FileStatus eachFile: files) {
         if (eachFile.isFile()) {