Fix some IntelliJ inspections (#7273)

Prepare TeamCity for IntelliJ 2018.3.1 upgrade. Mostly removed redundant exceptions declarations in `throws` clauses.

.idea/inspectionProfiles/Druid.xml

@@ -79,6 +79,9 @@
     <inspection_tool class="IteratorHasNextCallsIteratorNext" enabled="true" level="ERROR" enabled_by_default="true" />
     <inspection_tool class="IteratorNextDoesNotThrowNoSuchElementException" enabled="true" level="WARNING" enabled_by_default="true" />
     <inspection_tool class="Java8MapForEach" enabled="true" level="ERROR" enabled_by_default="true" />
+    <inspection_tool class="JavadocReference" enabled="true" level="ERROR" enabled_by_default="true">
+      <option name="REPORT_INACCESSIBLE" value="false" />
+    </inspection_tool>
     <inspection_tool class="JsonDuplicatePropertyKeys" enabled="true" level="ERROR" enabled_by_default="true" />
     <inspection_tool class="JsonStandardCompliance" enabled="true" level="WARNING" enabled_by_default="true" />
     <inspection_tool class="LengthOneStringInIndexOf" enabled="true" level="ERROR" enabled_by_default="true" />

core/src/main/java/org/apache/druid/data/input/impl/prefetch/PrefetchSqlFirehoseFactory.java

@@ -147,7 +147,6 @@ public abstract class PrefetchSqlFirehoseFactory<T>
 
   @Override
   public Firehose connect(InputRowParser<Map<String, Object>> firehoseParser, @Nullable File temporaryDirectory)
-      throws IOException
   {
     if (objects == null) {
       objects = ImmutableList.copyOf(Preconditions.checkNotNull(initObjects(), "objects"));

core/src/main/java/org/apache/druid/tasklogs/NoopTaskLogs.java

@@ -24,7 +24,6 @@ import com.google.common.io.ByteSource;
 import org.apache.druid.java.util.common.logger.Logger;
 
 import java.io.File;
-import java.io.IOException;
 
 public class NoopTaskLogs implements TaskLogs
 {
@@ -43,7 +42,7 @@ public class NoopTaskLogs implements TaskLogs
   }
 
   @Override
-  public void pushTaskReports(String taskid, File reportFile) throws IOException
+  public void pushTaskReports(String taskid, File reportFile)
   {
     log.info("Not pushing reports for task: %s", taskid);
   }

core/src/test/java/org/apache/druid/segment/loading/NoopDataSegmentArchiver.java

@@ -30,14 +30,14 @@ public class NoopDataSegmentArchiver implements DataSegmentArchiver
 {
   @Nullable
   @Override
-  public DataSegment archive(DataSegment segment) throws SegmentLoadingException
+  public DataSegment archive(DataSegment segment)
   {
     return segment;
   }
 
   @Nullable
   @Override
-  public DataSegment restore(DataSegment segment) throws SegmentLoadingException
+  public DataSegment restore(DataSegment segment)
   {
     return segment;
   }

core/src/test/java/org/apache/druid/segment/loading/NoopDataSegmentKiller.java

@@ -21,20 +21,18 @@ package org.apache.druid.segment.loading;
 
 import org.apache.druid.timeline.DataSegment;
 
-import java.io.IOException;
-
 /**
  * Mostly used for test purpose.
  */
 public class NoopDataSegmentKiller implements DataSegmentKiller
 {
   @Override
-  public void kill(DataSegment segments) throws SegmentLoadingException
+  public void kill(DataSegment segments)
   {
   }
 
   @Override
-  public void killAll() throws IOException
+  public void killAll()
   {
   }
 }

extensions-contrib/azure-extensions/src/main/java/org/apache/druid/storage/azure/AzureTaskLogs.java

@@ -57,7 +57,7 @@ public class AzureTaskLogs implements TaskLogs
   }
 
   @Override
-  public void pushTaskReports(String taskid, File reportFile) throws IOException
+  public void pushTaskReports(String taskid, File reportFile)
   {
     final String taskKey = getTaskReportsKey(taskid);
     log.info("Pushing task reports %s to: %s", reportFile, taskKey);

extensions-contrib/materialized-view-maintenance/src/test/java/org/apache/druid/indexing/materializedview/DerivativeDataSourceMetadataTest.java

@@ -34,7 +34,7 @@ public class DerivativeDataSourceMetadataTest
   public ExpectedException expectedException = ExpectedException.none();
 
   @Test
-  public void testEmptyBaseDataSource() throws Exception
+  public void testEmptyBaseDataSource()
   {
     expectedException.expect(CoreMatchers.instanceOf(IllegalArgumentException.class));
     expectedException.expectMessage(
@@ -47,7 +47,7 @@ public class DerivativeDataSourceMetadataTest
   }
 
   @Test
-  public void testNullBaseDataSource() throws Exception
+  public void testNullBaseDataSource()
   {
     expectedException.expect(CoreMatchers.instanceOf(IllegalArgumentException.class));
     expectedException.expectMessage(

extensions-contrib/materialized-view-maintenance/src/test/java/org/apache/druid/indexing/materializedview/MaterializedViewSupervisorSpecTest.java

@@ -199,7 +199,7 @@ public class MaterializedViewSupervisorSpecTest
   }
 
   @Test
-  public void testEmptyBaseDataSource() throws Exception
+  public void testEmptyBaseDataSource()
   {
     expectedException.expect(CoreMatchers.instanceOf(IllegalArgumentException.class));
     expectedException.expectMessage(
@@ -244,7 +244,7 @@ public class MaterializedViewSupervisorSpecTest
   }
 
   @Test
-  public void testNullBaseDataSource() throws Exception
+  public void testNullBaseDataSource()
   {
     expectedException.expect(CoreMatchers.instanceOf(IllegalArgumentException.class));
     expectedException.expectMessage(

extensions-contrib/orc-extensions/src/main/java/org/apache/druid/data/input/orc/OrcHadoopInputRowParser.java

@@ -246,15 +246,14 @@ public class OrcHadoopInputRowParser implements InputRowParser<OrcStruct>
     builder.append(parseSpec.getTimestampSpec().getTimestampColumn()).append(":string");
     // the typeString seems positionally dependent, so repeated timestamp column causes incorrect mapping
     if (parseSpec.getDimensionsSpec().getDimensionNames().size() > 0) {
-      builder.append(",");
-      builder.append(String.join(
-          ":string,",
-          parseSpec.getDimensionsSpec()
-                   .getDimensionNames()
-                   .stream()
-                   .filter(s -> !s.equals(parseSpec.getTimestampSpec().getTimestampColumn()))
-                   .collect(Collectors.toList())));
-      builder.append(":string");
+      builder.append(
+          parseSpec
+              .getDimensionsSpec()
+              .getDimensionNames()
+              .stream()
+              .filter(s -> !s.equals(parseSpec.getTimestampSpec().getTimestampColumn()))
+              .collect(Collectors.joining(":string,", ",", ":string"))
+      );
     }
     builder.append(">");
 

extensions-contrib/redis-cache/src/main/java/org/apache/druid/client/cache/RedisCache.java

@@ -30,7 +30,6 @@ import redis.clients.jedis.JedisPool;
 import redis.clients.jedis.JedisPoolConfig;
 import redis.clients.jedis.exceptions.JedisException;
 
-import java.io.IOException;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -151,7 +150,7 @@ public class RedisCache implements Cache
 
   @Override
   @LifecycleStop
-  public void close() throws IOException
+  public void close()
   {
     pool.close();
   }

extensions-core/histogram/src/main/java/org/apache/druid/query/aggregation/histogram/FixedBucketsHistogramAggregatorFactory.java

@@ -26,7 +26,6 @@ import org.apache.druid.java.util.common.StringUtils;
 import org.apache.druid.query.aggregation.AggregateCombiner;
 import org.apache.druid.query.aggregation.Aggregator;
 import org.apache.druid.query.aggregation.AggregatorFactory;
-import org.apache.druid.query.aggregation.AggregatorFactoryNotMergeableException;
 import org.apache.druid.query.aggregation.AggregatorUtil;
 import org.apache.druid.query.aggregation.BufferAggregator;
 import org.apache.druid.query.aggregation.ObjectAggregateCombiner;
@@ -172,7 +171,7 @@ public class FixedBucketsHistogramAggregatorFactory extends AggregatorFactory
   }
 
   @Override
-  public AggregatorFactory getMergingFactory(AggregatorFactory other) throws AggregatorFactoryNotMergeableException
+  public AggregatorFactory getMergingFactory(AggregatorFactory other)
   {
     return new FixedBucketsHistogramAggregatorFactory(
         name,

indexing-hadoop/src/test/java/org/apache/druid/indexer/HadoopDruidIndexerMapperTest.java

@@ -50,7 +50,6 @@ import org.junit.Test;
 
 import java.io.DataInput;
 import java.io.DataOutput;
-import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
@@ -242,13 +241,13 @@ public class HadoopDruidIndexerMapperTest
       }
 
       @Override
-      public void write(DataOutput out) throws IOException
+      public void write(DataOutput out)
       {
 
       }
 
       @Override
-      public void readFields(DataInput in) throws IOException
+      public void readFields(DataInput in)
       {
 
       }

indexing-service/src/main/java/org/apache/druid/indexing/common/task/AppenderatorDriverRealtimeIndexTask.java

@@ -233,7 +233,7 @@ public class AppenderatorDriverRealtimeIndexTask extends AbstractTask implements
   }
 
   @Override
-  public TaskStatus run(final TaskToolbox toolbox) throws Exception
+  public TaskStatus run(final TaskToolbox toolbox)
   {
     runThread = Thread.currentThread();
 

indexing-service/src/main/java/org/apache/druid/indexing/common/task/HadoopIndexTask.java

@@ -230,7 +230,7 @@ public class HadoopIndexTask extends HadoopTask implements ChatHandler
   }
 
   @Override
-  public TaskStatus run(TaskToolbox toolbox) throws Exception
+  public TaskStatus run(TaskToolbox toolbox)
   {
     try {
       taskConfig = toolbox.getConfig();

indexing-service/src/test/java/org/apache/druid/indexing/overlord/supervisor/SupervisorResourceTest.java

@@ -741,7 +741,7 @@ public class SupervisorResourceTest extends EasyMockSupport
   }
 
   @Test
-  public void testSpecGetHistoryWithAuthFailure() throws Exception
+  public void testSpecGetHistoryWithAuthFailure()
   {
     List<VersionedSupervisorSpec> versions1 = ImmutableList.of(
         new VersionedSupervisorSpec(

processing/src/main/java/org/apache/druid/segment/data/GenericIndexed.java

@@ -468,7 +468,7 @@ public class GenericIndexed<T> implements CloseableIndexed<T>, Serializer
   }
 
   @Override
-  public void close() throws IOException
+  public void close()
   {
     // nothing to close
   }

processing/src/test/java/org/apache/druid/query/aggregation/first/StringFirstBufferAggregatorTest.java

@@ -45,7 +45,7 @@ public class StringFirstBufferAggregatorTest
   }
 
   @Test
-  public void testBufferAggregate() throws Exception
+  public void testBufferAggregate()
   {
 
     final long[] timestamps = {1526724600L, 1526724700L, 1526724800L, 1526725900L, 1526725000L};
@@ -89,7 +89,7 @@ public class StringFirstBufferAggregatorTest
   }
 
   @Test
-  public void testNullBufferAggregate() throws Exception
+  public void testNullBufferAggregate()
   {
 
     final long[] timestamps = {2222L, 1111L, 3333L, 4444L, 5555L};

processing/src/test/java/org/apache/druid/query/aggregation/last/StringLastBufferAggregatorTest.java

@@ -45,7 +45,7 @@ public class StringLastBufferAggregatorTest
   }
 
   @Test
-  public void testBufferAggregate() throws Exception
+  public void testBufferAggregate()
   {
 
     final long[] timestamps = {1526724600L, 1526724700L, 1526724800L, 1526725900L, 1526725000L};
@@ -89,7 +89,7 @@ public class StringLastBufferAggregatorTest
   }
 
   @Test
-  public void testNullBufferAggregate() throws Exception
+  public void testNullBufferAggregate()
   {
 
     final long[] timestamps = {1111L, 2222L, 6666L, 4444L, 5555L};

server/src/main/java/org/apache/druid/client/cache/CaffeineCache.java

@@ -34,7 +34,6 @@ import org.apache.druid.java.util.emitter.service.ServiceEmitter;
 import org.apache.druid.java.util.emitter.service.ServiceMetricEvent;
 import org.apache.druid.utils.JvmUtils;
 
-import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.util.Map;
 import java.util.OptionalLong;
@@ -119,7 +118,7 @@ public class CaffeineCache implements org.apache.druid.client.cache.Cache
 
   @Override
   @LifecycleStop
-  public void close() throws IOException
+  public void close()
   {
     cache.cleanUp();
   }

server/src/main/java/org/apache/druid/client/cache/MapCache.java

@@ -23,7 +23,6 @@ import com.google.common.primitives.Ints;
 import org.apache.druid.java.util.common.lifecycle.LifecycleStop;
 import org.apache.druid.java.util.emitter.service.ServiceEmitter;
 
-import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.util.ArrayList;
 import java.util.Collections;
@@ -148,7 +147,7 @@ public class MapCache implements Cache
 
   @Override
   @LifecycleStop
-  public void close() throws IOException
+  public void close()
   {
     baseMap.clear();
     byteCountingLRUMap.clear();

server/src/main/java/org/apache/druid/client/cache/MemcachedCache.java

@@ -598,7 +598,7 @@ public class MemcachedCache implements Cache
 
   @Override
   @LifecycleStop
-  public void close() throws IOException
+  public void close()
   {
     monitor.stop();
   }

server/src/main/java/org/apache/druid/curator/PotentiallyGzippedCompressionProvider.java

@@ -37,13 +37,13 @@ public class PotentiallyGzippedCompressionProvider implements CompressionProvide
   }
 
   @Override
-  public byte[] compress(String path, byte[] data) throws Exception
+  public byte[] compress(String path, byte[] data)
   {
     return compressOutput ? base.compress(path, data) : data;
   }
 
   @Override
-  public byte[] decompress(String path, byte[] data) throws Exception
+  public byte[] decompress(String path, byte[] data)
   {
     try {
       return base.decompress(path, data);

server/src/main/java/org/apache/druid/server/security/AllowOptionsResourceFilter.java

@@ -42,7 +42,7 @@ public class AllowOptionsResourceFilter implements Filter
   }
 
   @Override
-  public void init(FilterConfig filterConfig) throws ServletException
+  public void init(FilterConfig filterConfig)
   {
 
   }

server/src/test/java/org/apache/druid/segment/indexing/DataSchemaTest.java

@@ -287,7 +287,7 @@ public class DataSchemaTest
   }
   
   @Test
-  public void testEmptyDatasource() throws Exception
+  public void testEmptyDatasource()
   {
     Map<String, Object> parser = jsonMapper.convertValue(
         new StringInputRowParser(

server/src/test/java/org/apache/druid/segment/realtime/appenderator/StreamAppenderatorDriverTest.java

@@ -100,7 +100,7 @@ public class StreamAppenderatorDriverTest extends EasyMockSupport
   private DataSegmentKiller dataSegmentKiller;
 
   @Before
-  public void setUp() throws Exception
+  public void setUp()
   {
     appenderatorTester = new AppenderatorTester(MAX_ROWS_IN_MEMORY);
     allocator = new TestSegmentAllocator(DATA_SOURCE, Granularities.HOUR);

server/src/test/java/org/apache/druid/segment/realtime/firehose/EventReceiverFirehoseIdleTest.java

@@ -55,7 +55,7 @@ public class EventReceiverFirehoseIdleTest
   private HttpServletRequest req;
 
   @Before
-  public void setUp() throws Exception
+  public void setUp()
   {
     req = EasyMock.createMock(HttpServletRequest.class);
     eventReceiverFirehoseFactory = new EventReceiverFirehoseFactory(

sql/src/main/java/org/apache/druid/sql/http/ResultFormat.java

@@ -68,7 +68,7 @@ public enum ResultFormat
     }
 
     @Override
-    public Writer createFormatter(final OutputStream outputStream, final ObjectMapper jsonMapper) throws IOException
+    public Writer createFormatter(final OutputStream outputStream, final ObjectMapper jsonMapper)
     {
       return new CsvWriter(outputStream);
     }