Fix serde for ArrayOfDoublesSketchConstantPostAggregator. (#16550)

* Fix serde for ArrayOfDoublesSketchConstantPostAggregator.

The version originally added in #13819 was missing an annotation for
the "value" property. Fixes #16539.

Line endings for ArrayOfDoublesSketchConstantPostAggregator.java are changed
from \r\n to \n.

Adds a serde test, and improves various other datasketches post-aggregator
serde tests to deserialize into PostAggregator. This verifies that the type
information is set up correctly.

* Fix excessive imports.

* Fix equals, hashCode.

extensions-core/datasketches/src/main/java/org/apache/druid/query/aggregation/datasketches/tuple/ArrayOfDoublesSketchConstantPostAggregator.java

@@ -1,129 +1,129 @@
-/*
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF 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 org.apache.druid.query.aggregation.datasketches.tuple;
-
-import com.fasterxml.jackson.annotation.JsonCreator;
-import com.fasterxml.jackson.annotation.JsonProperty;
-import com.google.common.base.Preconditions;
-import org.apache.commons.codec.digest.DigestUtils;
-import org.apache.datasketches.tuple.arrayofdoubles.ArrayOfDoublesSketch;
-import org.apache.druid.java.util.common.guava.Comparators;
-import org.apache.druid.query.aggregation.AggregatorFactory;
-import org.apache.druid.query.aggregation.AggregatorUtil;
-import org.apache.druid.query.cache.CacheKeyBuilder;
-
-import java.util.Collections;
-import java.util.Comparator;
-import java.util.Map;
-import java.util.Objects;
-import java.util.Set;
-
-/**
- * This post-aggregator converts a given Base64 encoded string to an ArrayOfDoublesSketch.
- * The input column contains name of post-aggregator output and base64 encoded input string.
- * The output is a deserialized {@link ArrayOfDoublesSketch} .
- */
-public class ArrayOfDoublesSketchConstantPostAggregator extends ArrayOfDoublesSketchPostAggregator
-{
-
-  private final String value;
-  private final ArrayOfDoublesSketch sketchValue;
-
-  @JsonCreator
-  public ArrayOfDoublesSketchConstantPostAggregator(@JsonProperty("name") String name, @JsonProperty("value") String value)
-  {
-    super(name);
-    Preconditions.checkArgument(value != null && !value.isEmpty(),
-        "Constant value cannot be null or empty, expecting base64 encoded sketch string");
-    this.value = value;
-    this.sketchValue = ArrayOfDoublesSketchOperations.deserializeFromBase64EncodedStringSafe(value);
-  }
-
-  @Override
-  public Set<String> getDependentFields()
-  {
-    return Collections.emptySet();
-  }
-
-  @Override
-  public Comparator getComparator()
-  {
-    return Comparators.alwaysEqual();
-  }
-
-  @Override
-  public Object compute(Map<String, Object> combinedAggregators)
-  {
-    return sketchValue;
-  }
-
-  @Override
-  public ArrayOfDoublesSketchConstantPostAggregator decorate(Map<String, AggregatorFactory> aggregators)
-  {
-    return this;
-  }
-
-  public ArrayOfDoublesSketch getSketchValue()
-  {
-    return sketchValue;
-  }
-
-  @Override
-  public String toString()
-  {
-    return "ArrayOfDoublesSketchConstantPostAggregator{name='" + this.getName() + "', value='" + value + "'}";
-  }
-
-  private String getRawSketchValue()
-  {
-    return value;
-  }
-
-  @Override
-  public boolean equals(Object o)
-  {
-    if (this == o) {
-      return true;
-    }
-    if (o == null || getClass() != o.getClass()) {
-      return false;
-    }
-    ArrayOfDoublesSketchConstantPostAggregator that = (ArrayOfDoublesSketchConstantPostAggregator) o;
-    if (!(Objects.equals(this.getName(), that.getName()) && Objects.equals(this.value, that.value)
-        && Objects.equals(this.getSketchValue(), that.getSketchValue()))) {
-      return false;
-    }
-    return true;
-  }
-
-  @Override
-  public int hashCode()
-  {
-    return Objects.hash(super.hashCode(), value, sketchValue);
-  }
-
-  @Override
-  public byte[] getCacheKey()
-  {
-    return new CacheKeyBuilder(AggregatorUtil.ARRAY_OF_DOUBLES_SKETCH_CONSTANT_SKETCH_CACHE_TYPE_ID)
-        .appendString(DigestUtils.sha1Hex(value)).build();
-  }
-}
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF 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 org.apache.druid.query.aggregation.datasketches.tuple;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.google.common.base.Preconditions;
+import org.apache.commons.codec.digest.DigestUtils;
+import org.apache.datasketches.tuple.arrayofdoubles.ArrayOfDoublesSketch;
+import org.apache.druid.java.util.common.guava.Comparators;
+import org.apache.druid.query.aggregation.AggregatorFactory;
+import org.apache.druid.query.aggregation.AggregatorUtil;
+import org.apache.druid.query.cache.CacheKeyBuilder;
+
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Set;
+
+/**
+ * This post-aggregator converts a given Base64 encoded string to an ArrayOfDoublesSketch.
+ * The input column contains name of post-aggregator output and base64 encoded input string.
+ * The output is a deserialized {@link ArrayOfDoublesSketch} .
+ */
+public class ArrayOfDoublesSketchConstantPostAggregator extends ArrayOfDoublesSketchPostAggregator
+{
+
+  private final String value;
+  private final ArrayOfDoublesSketch sketchValue;
+
+  @JsonCreator
+  public ArrayOfDoublesSketchConstantPostAggregator(@JsonProperty("name") String name, @JsonProperty("value") String value)
+  {
+    super(name);
+    Preconditions.checkArgument(value != null && !value.isEmpty(),
+        "Constant value cannot be null or empty, expecting base64 encoded sketch string");
+    this.value = value;
+    this.sketchValue = ArrayOfDoublesSketchOperations.deserializeFromBase64EncodedStringSafe(value);
+  }
+
+  @Override
+  public Set<String> getDependentFields()
+  {
+    return Collections.emptySet();
+  }
+
+  @Override
+  public Comparator getComparator()
+  {
+    return Comparators.alwaysEqual();
+  }
+
+  @Override
+  public Object compute(Map<String, Object> combinedAggregators)
+  {
+    return sketchValue;
+  }
+
+  @Override
+  public ArrayOfDoublesSketchConstantPostAggregator decorate(Map<String, AggregatorFactory> aggregators)
+  {
+    return this;
+  }
+
+  public ArrayOfDoublesSketch getSketchValue()
+  {
+    return sketchValue;
+  }
+
+  @Override
+  public String toString()
+  {
+    return "ArrayOfDoublesSketchConstantPostAggregator{name='" + this.getName() + "', value='" + value + "'}";
+  }
+
+  @JsonProperty("value")
+  private String getRawSketchValue()
+  {
+    return value;
+  }
+
+  @Override
+  public boolean equals(Object o)
+  {
+    if (this == o) {
+      return true;
+    }
+    if (o == null || getClass() != o.getClass()) {
+      return false;
+    }
+    if (!super.equals(o)) {
+      return false;
+    }
+    ArrayOfDoublesSketchConstantPostAggregator that = (ArrayOfDoublesSketchConstantPostAggregator) o;
+    return Objects.equals(value, that.value);
+  }
+
+  @Override
+  public int hashCode()
+  {
+    return Objects.hash(super.hashCode(), value);
+  }
+
+  @Override
+  public byte[] getCacheKey()
+  {
+    return new CacheKeyBuilder(AggregatorUtil.ARRAY_OF_DOUBLES_SKETCH_CONSTANT_SKETCH_CACHE_TYPE_ID)
+        .appendString(DigestUtils.sha1Hex(value)).build();
+  }
+}

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/hll/HllSketchToEstimatePostAggregatorTest.java

@@ -45,9 +45,10 @@ public class HllSketchToEstimatePostAggregatorTest
         true
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    HllSketchToEstimatePostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new HllSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        HllSketchToEstimatePostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/hll/HllSketchToEstimateWithBoundsPostAggregatorTest.java

@@ -38,9 +38,10 @@ public class HllSketchToEstimateWithBoundsPostAggregatorTest
         2
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    HllSketchToEstimateWithBoundsPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new HllSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        HllSketchToEstimateWithBoundsPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/hll/HllSketchToStringPostAggregatorTest.java

@@ -37,9 +37,10 @@ public class HllSketchToStringPostAggregatorTest
         new FieldAccessPostAggregator("field1", "sketch")
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    HllSketchToStringPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new HllSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        HllSketchToStringPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/hll/HllSketchUnionPostAggregatorTest.java

@@ -45,9 +45,10 @@ public class HllSketchUnionPostAggregatorTest
         TgtHllType.HLL_8.name()
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    HllSketchUnionPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new HllSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        HllSketchUnionPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/kll/KllDoublesSketchToCDFPostAggregatorTest.java

@@ -55,9 +55,10 @@ public class KllDoublesSketchToCDFPostAggregatorTest
         new double[]{0.25, 0.75}
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    KllDoublesSketchToCDFPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new KllSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        KllDoublesSketchToCDFPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/kll/KllDoublesSketchToHistogramPostAggregatorTest.java

@@ -56,9 +56,10 @@ public class KllDoublesSketchToHistogramPostAggregatorTest
         null
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    KllDoublesSketchToHistogramPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new KllSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        KllDoublesSketchToHistogramPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/kll/KllDoublesSketchToQuantilePostAggregatorTest.java

@@ -38,9 +38,10 @@ public class KllDoublesSketchToQuantilePostAggregatorTest
         0.5
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    KllDoublesSketchToQuantilePostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new KllSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        KllDoublesSketchToQuantilePostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/kll/KllDoublesSketchToQuantilesPostAggregatorTest.java

@@ -55,9 +55,10 @@ public class KllDoublesSketchToQuantilesPostAggregatorTest
         new double[] {0, 0.5, 1}
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    KllDoublesSketchToQuantilesPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new KllSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        KllDoublesSketchToQuantilesPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/kll/KllDoublesSketchToRankPostAggregatorTest.java

@@ -49,9 +49,10 @@ public class KllDoublesSketchToRankPostAggregatorTest
         0
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    KllDoublesSketchToRankPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new KllSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        KllDoublesSketchToRankPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/kll/KllDoublesSketchToStringPostAggregatorTest.java

@@ -43,9 +43,10 @@ public class KllDoublesSketchToStringPostAggregatorTest
         new FieldAccessPostAggregator("field1", "sketch")
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    KllDoublesSketchToStringPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new KllSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        KllDoublesSketchToStringPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/kll/KllFloatsSketchToCDFPostAggregatorTest.java

@@ -55,9 +55,10 @@ public class KllFloatsSketchToCDFPostAggregatorTest
         new float[]{0.25f, 0.75f}
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    KllFloatsSketchToCDFPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new KllSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        KllFloatsSketchToCDFPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/kll/KllFloatsSketchToHistogramPostAggregatorTest.java

@@ -56,9 +56,10 @@ public class KllFloatsSketchToHistogramPostAggregatorTest
         null
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    KllFloatsSketchToHistogramPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new KllSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        KllFloatsSketchToHistogramPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/kll/KllFloatsSketchToQuantilePostAggregatorTest.java

@@ -38,9 +38,10 @@ public class KllFloatsSketchToQuantilePostAggregatorTest
         0.5
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    KllFloatsSketchToQuantilePostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new KllSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        KllFloatsSketchToQuantilePostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/kll/KllFloatsSketchToQuantilesPostAggregatorTest.java

@@ -55,9 +55,10 @@ public class KllFloatsSketchToQuantilesPostAggregatorTest
         new double[] {0, 0.5, 1}
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    KllFloatsSketchToQuantilesPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new KllSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        KllFloatsSketchToQuantilesPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/kll/KllFloatsSketchToRankPostAggregatorTest.java

@@ -49,9 +49,10 @@ public class KllFloatsSketchToRankPostAggregatorTest
         0
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    KllFloatsSketchToRankPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new KllSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        KllFloatsSketchToRankPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/kll/KllFloatsSketchToStringPostAggregatorTest.java

@@ -43,9 +43,10 @@ public class KllFloatsSketchToStringPostAggregatorTest
         new FieldAccessPostAggregator("field1", "sketch")
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    KllFloatsSketchToStringPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new KllSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        KllFloatsSketchToStringPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/quantiles/DoublesSketchToCDFPostAggregatorTest.java

@@ -55,9 +55,10 @@ public class DoublesSketchToCDFPostAggregatorTest
         new double[]{0.25, 0.75}
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    DoublesSketchToCDFPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new DoublesSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        DoublesSketchToCDFPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/quantiles/DoublesSketchToHistogramPostAggregatorTest.java

@@ -56,9 +56,10 @@ public class DoublesSketchToHistogramPostAggregatorTest
         null
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    DoublesSketchToHistogramPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new DoublesSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        DoublesSketchToHistogramPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/quantiles/DoublesSketchToQuantilePostAggregatorTest.java

@@ -38,9 +38,10 @@ public class DoublesSketchToQuantilePostAggregatorTest
         0.5
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    DoublesSketchToQuantilePostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new DoublesSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        DoublesSketchToQuantilePostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/quantiles/DoublesSketchToQuantilesPostAggregatorTest.java

@@ -55,9 +55,10 @@ public class DoublesSketchToQuantilesPostAggregatorTest
         new double[] {0, 0.5, 1}
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    DoublesSketchToQuantilesPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new DoublesSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        DoublesSketchToQuantilesPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/quantiles/DoublesSketchToRankPostAggregatorTest.java

@@ -49,9 +49,10 @@ public class DoublesSketchToRankPostAggregatorTest
         0
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    DoublesSketchToRankPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new DoublesSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        DoublesSketchToRankPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/quantiles/DoublesSketchToStringPostAggregatorTest.java

@@ -43,9 +43,10 @@ public class DoublesSketchToStringPostAggregatorTest
         new FieldAccessPostAggregator("field1", "sketch")
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    DoublesSketchToStringPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new DoublesSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        DoublesSketchToStringPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/theta/SketchSetPostAggregatorTest.java

@@ -85,11 +85,13 @@ public class SketchSetPostAggregatorTest
     );
     List<PostAggregator> serdeTests = Arrays.asList(union, intersect, not);
 
+    DefaultObjectMapper mapper = new DefaultObjectMapper();
+    mapper.registerModules(new SketchModule().getJacksonModules());
+
     for (PostAggregator there : serdeTests) {
-      DefaultObjectMapper mapper = new DefaultObjectMapper();
-      SketchSetPostAggregator andBackAgain = mapper.readValue(
+      PostAggregator andBackAgain = mapper.readValue(
           mapper.writeValueAsString(there),
-          SketchSetPostAggregator.class
+          PostAggregator.class
       );
 
       Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/theta/SketchToStringPostAggregatorTest.java

@@ -47,9 +47,10 @@ public class SketchToStringPostAggregatorTest
         new FieldAccessPostAggregator("field", "sketch")
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    SketchToStringPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new SketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        SketchToStringPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/tuple/ArrayOfDoublesSketchConstantPostAggregatorTest.java

@@ -19,7 +19,9 @@
 
 package org.apache.druid.query.aggregation.datasketches.tuple;
 
+import com.fasterxml.jackson.core.JsonProcessingException;
 import nl.jqno.equalsverifier.EqualsVerifier;
+import org.apache.druid.jackson.DefaultObjectMapper;
 import org.apache.druid.java.util.common.guava.Comparators;
 import org.apache.druid.query.aggregation.PostAggregator;
 import org.junit.Assert;
@@ -28,7 +30,6 @@ import org.junit.Test;
 
 public class ArrayOfDoublesSketchConstantPostAggregatorTest
 {
-
   @Test
   public void testSketchValue()
   {
@@ -66,12 +67,32 @@ public class ArrayOfDoublesSketchConstantPostAggregatorTest
     Assert.assertEquals(Comparators.alwaysEqual(), postAgg.getComparator());
   }
 
+  @Test
+  public void testSerde() throws JsonProcessingException
+  {
+    final PostAggregator there = new ArrayOfDoublesSketchConstantPostAggregator(
+        "p",
+        "AQEJAwgBzJP/////////fwIAAAAAAAAAzT6NGdX0aWUOJvS5EIhpLwAAAAAAAAAAAAAAAAAAAAA="
+    );
+    DefaultObjectMapper mapper = new DefaultObjectMapper();
+    mapper.registerModules(new ArrayOfDoublesSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
+        mapper.writeValueAsString(there),
+        PostAggregator.class
+    );
+
+    Assert.assertEquals(there, andBackAgain);
+    Assert.assertArrayEquals(there.getCacheKey(), andBackAgain.getCacheKey());
+  }
+
   @Test
   public void testEqualsAndHashCode()
   {
     EqualsVerifier.forClass(ArrayOfDoublesSketchConstantPostAggregator.class)
-        .usingGetClass()
-        .verify();
+                  .usingGetClass()
+                  .withNonnullFields("name")
+                  .withIgnoredFields("sketchValue")
+                  .verify();
   }
 }
 

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/tuple/ArrayOfDoublesSketchSetOpPostAggregatorTest.java

@@ -76,9 +76,10 @@ public class ArrayOfDoublesSketchSetOpPostAggregatorTest
         Arrays.asList(new ConstantPostAggregator("", 0), new ConstantPostAggregator("", 0))
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    ArrayOfDoublesSketchSetOpPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new ArrayOfDoublesSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        ArrayOfDoublesSketchSetOpPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/tuple/ArrayOfDoublesSketchTTestPostAggregatorTest.java

@@ -84,9 +84,10 @@ public class ArrayOfDoublesSketchTTestPostAggregatorTest
         Arrays.asList(new ConstantPostAggregator("", 0), new ConstantPostAggregator("", 0))
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    ArrayOfDoublesSketchTTestPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new ArrayOfDoublesSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        ArrayOfDoublesSketchTTestPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/tuple/ArrayOfDoublesSketchToBase64StringPostAggregatorTest.java

@@ -51,9 +51,10 @@ public class ArrayOfDoublesSketchToBase64StringPostAggregatorTest
         new ConstantPostAggregator("", 0)
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    ArrayOfDoublesSketchToBase64StringPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new ArrayOfDoublesSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        ArrayOfDoublesSketchToBase64StringPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/tuple/ArrayOfDoublesSketchToEstimateAndBoundsPostAggregatorTest.java

@@ -44,9 +44,10 @@ public class ArrayOfDoublesSketchToEstimateAndBoundsPostAggregatorTest
         null
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    ArrayOfDoublesSketchToEstimateAndBoundsPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new ArrayOfDoublesSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        ArrayOfDoublesSketchToEstimateAndBoundsPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/tuple/ArrayOfDoublesSketchToEstimatePostAggregatorTest.java

@@ -50,9 +50,10 @@ public class ArrayOfDoublesSketchToEstimatePostAggregatorTest
         new ConstantPostAggregator("", 0)
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    ArrayOfDoublesSketchToEstimatePostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new ArrayOfDoublesSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        ArrayOfDoublesSketchToEstimatePostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/tuple/ArrayOfDoublesSketchToMeansPostAggregatorTest.java

@@ -50,9 +50,10 @@ public class ArrayOfDoublesSketchToMeansPostAggregatorTest
         new ConstantPostAggregator("", 0)
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    ArrayOfDoublesSketchToMeansPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new ArrayOfDoublesSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        ArrayOfDoublesSketchToMeansPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/tuple/ArrayOfDoublesSketchToMetricsSumEstimatePostAggregatorTest.java

@@ -52,9 +52,10 @@ public class ArrayOfDoublesSketchToMetricsSumEstimatePostAggregatorTest
         new ConstantPostAggregator("", 0)
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    ArrayOfDoublesSketchToMetricsSumEstimatePostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new ArrayOfDoublesSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        ArrayOfDoublesSketchToMetricsSumEstimatePostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/tuple/ArrayOfDoublesSketchToNumEntriesPostAggregatorTest.java

@@ -50,9 +50,10 @@ public class ArrayOfDoublesSketchToNumEntriesPostAggregatorTest
         new ConstantPostAggregator("", 0)
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    ArrayOfDoublesSketchToNumEntriesPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new ArrayOfDoublesSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        ArrayOfDoublesSketchToNumEntriesPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/tuple/ArrayOfDoublesSketchToQuantilesSketchPostAggregatorTest.java

@@ -54,9 +54,10 @@ public class ArrayOfDoublesSketchToQuantilesSketchPostAggregatorTest
         null
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    ArrayOfDoublesSketchToQuantilesSketchPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new ArrayOfDoublesSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        ArrayOfDoublesSketchToQuantilesSketchPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/tuple/ArrayOfDoublesSketchToStringPostAggregatorTest.java

@@ -50,9 +50,10 @@ public class ArrayOfDoublesSketchToStringPostAggregatorTest
         new ConstantPostAggregator("", 0)
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    ArrayOfDoublesSketchToStringPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new ArrayOfDoublesSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        ArrayOfDoublesSketchToStringPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);

extensions-core/datasketches/src/test/java/org/apache/druid/query/aggregation/datasketches/tuple/ArrayOfDoublesSketchToVariancesPostAggregatorTest.java

@@ -50,9 +50,10 @@ public class ArrayOfDoublesSketchToVariancesPostAggregatorTest
         new ConstantPostAggregator("", 0)
     );
     DefaultObjectMapper mapper = new DefaultObjectMapper();
-    ArrayOfDoublesSketchToVariancesPostAggregator andBackAgain = mapper.readValue(
+    mapper.registerModules(new ArrayOfDoublesSketchModule().getJacksonModules());
+    PostAggregator andBackAgain = mapper.readValue(
         mapper.writeValueAsString(there),
-        ArrayOfDoublesSketchToVariancesPostAggregator.class
+        PostAggregator.class
     );
 
     Assert.assertEquals(there, andBackAgain);