Fix merge for TrueDimFilter (#5916)

* Fix merge for TrueDimFilter

* remove unused cache ID

indexing-service/src/test/java/io/druid/indexing/firehose/IngestSegmentFirehoseFactoryTimelineTest.java

@@ -53,7 +53,7 @@ import io.druid.java.util.common.DateTimes;
 import io.druid.java.util.common.Intervals;
 import io.druid.java.util.common.JodaUtils;
 import io.druid.query.aggregation.LongSumAggregatorFactory;
-import io.druid.query.filter.NoopDimFilter;
+import io.druid.query.filter.TrueDimFilter;
 import io.druid.segment.IndexIO;
 import io.druid.segment.IndexMergerV9;
 import io.druid.segment.IndexSpec;
@@ -350,7 +350,7 @@ public class IngestSegmentFirehoseFactoryTimelineTest
       final IngestSegmentFirehoseFactory factory = new IngestSegmentFirehoseFactory(
           DATA_SOURCE,
           testCase.interval,
-          new NoopDimFilter(),
+          new TrueDimFilter(),
           Arrays.asList(DIMENSIONS),
           Arrays.asList(METRICS),
           INDEX_IO

processing/src/main/java/io/druid/query/filter/DimFilterUtils.java

@@ -36,7 +36,6 @@ import java.util.Set;
  */
 public class DimFilterUtils
 {
-  static final byte NOOP_CACHE_ID = -0x4;
   static final byte SELECTOR_CACHE_ID = 0x0;
   static final byte AND_CACHE_ID = 0x1;
   static final byte OR_CACHE_ID = 0x2;

processing/src/main/java/io/druid/query/filter/NoopDimFilter.java

@@ -1,60 +0,0 @@
-/*
- * Licensed to Metamarkets Group Inc. (Metamarkets) under one
- * or more contributor license agreements. See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership. Metamarkets licenses this file
- * to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance
- * with the License. You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing,
- * software distributed under the License is distributed on an
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
- * KIND, either express or implied. See the License for the
- * specific language governing permissions and limitations
- * under the License.
- */
-
-package io.druid.query.filter;
-
-import com.google.common.collect.RangeSet;
-
-import java.nio.ByteBuffer;
-import java.util.HashSet;
-
-/**
- */
-public class NoopDimFilter implements DimFilter
-{
-  @Override
-  public byte[] getCacheKey()
-  {        
-    return ByteBuffer.allocate(1).put(DimFilterUtils.NOOP_CACHE_ID).array();
-  }
-
-  @Override
-  public DimFilter optimize()
-  {
-    return this;
-  }
-
-  @Override
-  public Filter toFilter()
-  {
-    return null;
-  }
-
-  @Override
-  public RangeSet<String> getDimensionRangeSet(String dimension)
-  {
-    return null;
-  }
-
-  @Override
-  public HashSet<String> getRequiredColumns()
-  {
-    return null;
-  }
-}

processing/src/main/java/io/druid/query/filter/TrueDimFilter.java

@@ -23,11 +23,14 @@ import com.google.common.collect.RangeSet;
 import io.druid.segment.filter.TrueFilter;
 
 import java.nio.ByteBuffer;
+import java.util.HashSet;
 
 /**
  */
 public class TrueDimFilter implements DimFilter
 {
+  private static HashSet<String> REQUIRED_COLUMNS = new HashSet<>();
+
   @Override
   public byte[] getCacheKey()
   {        
@@ -51,4 +54,10 @@ public class TrueDimFilter implements DimFilter
   {
     return null;
   }
+
+  @Override
+  public HashSet<String> getRequiredColumns()
+  {
+    return REQUIRED_COLUMNS;
+  }
 }