Spotbugs: NP_NONNULL_PARAM_VIOLATION

codestyle/spotbugs-exclude.xml

@@ -60,8 +60,6 @@
     <Bug pattern="NP_LOAD_OF_KNOWN_NULL_VALUE"/>
     <Bug pattern="NP_METHOD_PARAMETER_TIGHTENS_ANNOTATION"/>
     <Bug pattern="NP_NONNULL_FIELD_NOT_INITIALIZED_IN_CONSTRUCTOR"/>
-    <Bug pattern="NP_NONNULL_PARAM_VIOLATION"/>
-    <Bug pattern="NP_NONNULL_PARAM_VIOLATION"/>
     <Bug pattern="NP_NONNULL_RETURN_VIOLATION"/>
     <Bug pattern="NP_NULL_ON_SOME_PATH"/>
     <Bug pattern="NP_NULL_ON_SOME_PATH_FROM_RETURN_VALUE"/>

core/src/main/java/org/apache/druid/collections/SerializablePair.java

@@ -23,10 +23,12 @@
 import com.fasterxml.jackson.annotation.JsonProperty;
 import org.apache.druid.java.util.common.Pair;
 
+import javax.annotation.Nullable;
+
 public class SerializablePair<T1, T2> extends Pair<T1, T2>
 {
   @JsonCreator
-  public SerializablePair(@JsonProperty("lhs") T1 lhs, @JsonProperty("rhs") T2 rhs)
+  public SerializablePair(@JsonProperty("lhs") T1 lhs, @JsonProperty("rhs") @Nullable T2 rhs)
   {
     super(lhs, rhs);
   }
@@ -38,6 +40,7 @@ public T1 getLhs()
   }
 
   @JsonProperty
+  @Nullable
   public T2 getRhs()
   {
     return rhs;

extensions-core/datasketches/src/main/java/org/apache/druid/query/aggregation/datasketches/theta/SketchEstimatePostAggregator.java

@@ -29,6 +29,8 @@
 import org.apache.druid.query.aggregation.post.PostAggregatorIds;
 import org.apache.druid.query.cache.CacheKeyBuilder;
 
+import javax.annotation.Nullable;
+
 import java.util.Comparator;
 import java.util.HashSet;
 import java.util.Map;
@@ -39,13 +41,14 @@ public class SketchEstimatePostAggregator implements PostAggregator
 
   private final String name;
   private final PostAggregator field;
+  @Nullable
   private final Integer errorBoundsStdDev;
 
   @JsonCreator
   public SketchEstimatePostAggregator(
       @JsonProperty("name") String name,
       @JsonProperty("field") PostAggregator field,
-      @JsonProperty("errorBoundsStdDev") Integer errorBoundsStdDev
+      @JsonProperty("errorBoundsStdDev") @Nullable Integer errorBoundsStdDev
   )
   {
     this.name = Preconditions.checkNotNull(name, "name is null");
@@ -56,9 +59,7 @@ public SketchEstimatePostAggregator(
   @Override
   public Set<String> getDependentFields()
   {
-    Set<String> dependentFields = new HashSet<>();
-    dependentFields.addAll(field.getDependentFields());
-    return dependentFields;
+    return new HashSet<>(field.getDependentFields());
   }
 
   @Override
@@ -111,6 +112,7 @@ public PostAggregator getField()
     return field;
   }
 
+  @Nullable
   @JsonProperty
   public Integer getErrorBoundsStdDev()
   {

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

@@ -23,6 +23,8 @@
 import com.google.common.base.Preconditions;
 import com.google.common.primitives.Floats;
 
+import javax.annotation.Nullable;
+
 import java.nio.ByteBuffer;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -470,11 +472,6 @@ protected void shiftLeft(int start, int end)
     }
   }
 
-  public ApproximateHistogram fold(ApproximateHistogram h)
-  {
-    return fold(h, null, null, null);
-  }
-
   public ApproximateHistogram fold(ApproximateHistogram h, float[] mergedPositions, long[] mergedBins, float[] deltas)
   {
     if (size == 0) {
@@ -496,7 +493,7 @@ public ApproximateHistogram foldFast(ApproximateHistogram h)
    *
    * @return returns this histogram with h folded into it
    */
-  public ApproximateHistogram foldFast(ApproximateHistogram h, float[] mergedPositions, long[] mergedBins)
+  public ApproximateHistogram foldFast(ApproximateHistogram h, @Nullable float[] mergedPositions, @Nullable long[] mergedBins)
   {
     if (size == 0) {
       return copy(h);
@@ -612,7 +609,7 @@ protected ApproximateHistogram foldMin(
     return this;
   }
 
-  protected ApproximateHistogram foldRule(ApproximateHistogram h, float[] mergedPositions, long[] mergedBins)
+  protected ApproximateHistogram foldRule(ApproximateHistogram h, @Nullable float[] mergedPositions, @Nullable long[] mergedBins)
   {
     // ruleCombine bins requires at least one bin
     if (h.binCount == 0) {
@@ -1079,8 +1076,8 @@ private static int combineBins(
       float[] rightPositions,
       long[] rightBins,
       float[] mergedPositions,
-      long[] mergedBins,
-      float[] deltas
+      @Nullable long[] mergedBins,
+      @Nullable float[] deltas
   )
   {
     int i = 0;

extensions-core/histogram/src/test/java/org/apache/druid/query/aggregation/histogram/ApproximateHistogramErrorBenchmark.java

@@ -144,7 +144,7 @@ private float[] getErrors()
     for (int i = 0; i < numValues; ++i) {
       tmp.offer(values[i]);
       if ((i + 1) % numPerHist == 0) {
-        ah1.fold(tmp);
+        ah1.fold(tmp, null, null, null);
         ah2.foldRule(tmp, null, null);
         tmp = new ApproximateHistogram(resolution);
       }

extensions-core/histogram/src/test/java/org/apache/druid/query/aggregation/histogram/ApproximateHistogramTest.java

@@ -111,8 +111,8 @@ public void testFold()
       h2.offer(VALUES[i]);
     }
 
-    merged.fold(h1);
-    merged.fold(h2);
+    merged.fold(h1, null, null, null);
+    merged.fold(h2, null, null, null);
     mergedFast.foldFast(h1);
     mergedFast.foldFast(h2);
 
@@ -144,7 +144,7 @@ public void testFold()
     ApproximateHistogram aFast = buildHistogram(10, new float[]{1, 2, 3, 4, 5, 6});
     ApproximateHistogram b = buildHistogram(5, new float[]{3, 4, 5, 6});
 
-    a.fold(b);
+    a.fold(b, null, null, null);
     aFast.foldFast(b);
 
     Assert.assertEquals(
@@ -172,7 +172,7 @@ public void testFold()
     for (float v : VALUES4) {
       h4.offer(v);
     }
-    h3.fold(h4);
+    h3.fold(h4, null, null, null);
     Assert.assertArrayEquals(
         "final bin positions match expected positions",
         new float[]{-50.98f, -21.77f, -9.81f, 3.73f, 13.72f, 20.1f, 29f, 44.79f, 53.8f, 64.67f},
@@ -191,7 +191,7 @@ public void testFoldNothing()
     ApproximateHistogram h1 = new ApproximateHistogram(10);
     ApproximateHistogram h2 = new ApproximateHistogram(10);
 
-    h1.fold(h2);
+    h1.fold(h2, null, null, null);
     h1.foldFast(h2);
   }
 
@@ -210,8 +210,8 @@ public void testFoldNothing2()
       h4Fast.offer(v);
     }
 
-    h1.fold(h3);
-    h4.fold(h2);
+    h1.fold(h3, null, null, null);
+    h4.fold(h2, null, null, null);
     h1Fast.foldFast(h3);
     h4Fast.foldFast(h2);
 
@@ -300,7 +300,7 @@ public void testSerializeCompact()
     ApproximateHistogram h = buildHistogram(5, VALUES);
     Assert.assertEquals(h, ApproximateHistogram.fromBytes(h.toBytes()));
 
-    ApproximateHistogram h2 = new ApproximateHistogram(50).fold(h);
+    ApproximateHistogram h2 = new ApproximateHistogram(50).fold(h, null, null, null);
     Assert.assertEquals(h2, ApproximateHistogram.fromBytes(h2.toBytes()));
   }
 
@@ -331,7 +331,7 @@ public void testSerializeCompactExact()
     h = buildHistogram(5, new float[]{1f, 2f, 3f});
     Assert.assertEquals(h, ApproximateHistogram.fromBytes(h.toBytes()));
 
-    h = new ApproximateHistogram(40).fold(h);
+    h = new ApproximateHistogram(40).fold(h, null, null, null);
     Assert.assertEquals(h, ApproximateHistogram.fromBytes(h.toBytes()));
   }
 

extensions-core/stats/src/main/java/org/apache/druid/query/aggregation/variance/VarianceAggregatorCollector.java

@@ -49,7 +49,7 @@
  */
 public class VarianceAggregatorCollector
 {
-  public static boolean isVariancePop(String estimator)
+  public static boolean isVariancePop(@Nullable String estimator)
   {
     return estimator != null && "population".equalsIgnoreCase(estimator);
   }

extensions-core/stats/src/main/java/org/apache/druid/query/aggregation/variance/VarianceAggregatorFactory.java

@@ -53,6 +53,7 @@ public class VarianceAggregatorFactory extends AggregatorFactory
 {
   protected final String fieldName;
   protected final String name;
+  @Nullable
   protected final String estimator;
   private final String inputType;
 
@@ -62,8 +63,8 @@ public class VarianceAggregatorFactory extends AggregatorFactory
   public VarianceAggregatorFactory(
       @JsonProperty("name") String name,
       @JsonProperty("fieldName") String fieldName,
-      @JsonProperty("estimator") String estimator,
-      @JsonProperty("inputType") String inputType
+      @JsonProperty("estimator") @Nullable String estimator,
+      @JsonProperty("inputType") @Nullable String inputType
   )
   {
     Preconditions.checkNotNull(name, "Must have a valid, non-null aggregator name");
@@ -238,6 +239,7 @@ public String getName()
     return name;
   }
 
+  @Nullable
   @JsonProperty
   public String getEstimator()
   {

extensions-core/stats/src/main/java/org/apache/druid/query/aggregation/variance/VarianceFoldingAggregatorFactory.java

@@ -22,6 +22,8 @@
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.annotation.JsonTypeName;
 
+import javax.annotation.Nullable;
+
 /**
  */
 @JsonTypeName("varianceFold")
@@ -30,7 +32,7 @@ public class VarianceFoldingAggregatorFactory extends VarianceAggregatorFactory
   public VarianceFoldingAggregatorFactory(
       @JsonProperty("name") String name,
       @JsonProperty("fieldName") String fieldName,
-      @JsonProperty("estimator") String estimator
+      @JsonProperty("estimator") @Nullable String estimator
   )
   {
     super(name, fieldName, estimator, "variance");

processing/src/main/java/org/apache/druid/query/aggregation/DoubleMaxAggregatorFactory.java

@@ -40,7 +40,7 @@ public class DoubleMaxAggregatorFactory extends SimpleDoubleAggregatorFactory
   public DoubleMaxAggregatorFactory(
       @JsonProperty("name") String name,
       @JsonProperty("fieldName") final String fieldName,
-      @JsonProperty("expression") String expression,
+      @JsonProperty("expression") @Nullable String expression,
       @JacksonInject ExprMacroTable macroTable
   )
   {

processing/src/main/java/org/apache/druid/query/aggregation/DoubleMinAggregatorFactory.java

@@ -40,7 +40,7 @@ public class DoubleMinAggregatorFactory extends SimpleDoubleAggregatorFactory
   public DoubleMinAggregatorFactory(
       @JsonProperty("name") String name,
       @JsonProperty("fieldName") final String fieldName,
-      @JsonProperty("expression") String expression,
+      @JsonProperty("expression") @Nullable String expression,
       @JacksonInject ExprMacroTable macroTable
   )
   {

processing/src/main/java/org/apache/druid/query/aggregation/DoubleSumAggregatorFactory.java

@@ -42,7 +42,7 @@ public class DoubleSumAggregatorFactory extends SimpleDoubleAggregatorFactory
   public DoubleSumAggregatorFactory(
       @JsonProperty("name") String name,
       @JsonProperty("fieldName") final String fieldName,
-      @JsonProperty("expression") String expression,
+      @JsonProperty("expression") @Nullable String expression,
       @JacksonInject ExprMacroTable macroTable
   )
   {

processing/src/main/java/org/apache/druid/query/aggregation/FloatMaxAggregatorFactory.java

@@ -40,7 +40,7 @@ public class FloatMaxAggregatorFactory extends SimpleFloatAggregatorFactory
   public FloatMaxAggregatorFactory(
       @JsonProperty("name") String name,
       @JsonProperty("fieldName") final String fieldName,
-      @JsonProperty("expression") String expression,
+      @JsonProperty("expression") @Nullable String expression,
       @JacksonInject ExprMacroTable macroTable
   )
   {

processing/src/main/java/org/apache/druid/query/aggregation/FloatMinAggregatorFactory.java

@@ -40,7 +40,7 @@ public class FloatMinAggregatorFactory extends SimpleFloatAggregatorFactory
   public FloatMinAggregatorFactory(
       @JsonProperty("name") String name,
       @JsonProperty("fieldName") final String fieldName,
-      @JsonProperty("expression") String expression,
+      @JsonProperty("expression") @Nullable String expression,
       @JacksonInject ExprMacroTable macroTable
   )
   {

processing/src/main/java/org/apache/druid/query/aggregation/FloatSumAggregatorFactory.java

@@ -42,7 +42,7 @@ public class FloatSumAggregatorFactory extends SimpleFloatAggregatorFactory
   public FloatSumAggregatorFactory(
       @JsonProperty("name") String name,
       @JsonProperty("fieldName") final String fieldName,
-      @JsonProperty("expression") String expression,
+      @JsonProperty("expression") @Nullable String expression,
       @JacksonInject ExprMacroTable macroTable
   )
   {

processing/src/main/java/org/apache/druid/query/aggregation/LongMaxAggregatorFactory.java

@@ -40,7 +40,7 @@ public class LongMaxAggregatorFactory extends SimpleLongAggregatorFactory
   public LongMaxAggregatorFactory(
       @JsonProperty("name") String name,
       @JsonProperty("fieldName") final String fieldName,
-      @JsonProperty("expression") String expression,
+      @JsonProperty("expression") @Nullable String expression,
       @JacksonInject ExprMacroTable macroTable
   )
   {

processing/src/main/java/org/apache/druid/query/aggregation/LongMinAggregatorFactory.java

@@ -40,7 +40,7 @@ public class LongMinAggregatorFactory extends SimpleLongAggregatorFactory
   public LongMinAggregatorFactory(
       @JsonProperty("name") String name,
       @JsonProperty("fieldName") final String fieldName,
-      @JsonProperty("expression") String expression,
+      @JsonProperty("expression") @Nullable String expression,
       @JacksonInject ExprMacroTable macroTable
   )
   {

processing/src/main/java/org/apache/druid/query/aggregation/LongSumAggregatorFactory.java

@@ -42,7 +42,7 @@ public class LongSumAggregatorFactory extends SimpleLongAggregatorFactory
   public LongSumAggregatorFactory(
       @JsonProperty("name") String name,
       @JsonProperty("fieldName") final String fieldName,
-      @JsonProperty("expression") String expression,
+      @JsonProperty("expression") @Nullable String expression,
       @JacksonInject ExprMacroTable macroTable
   )
   {

processing/src/main/java/org/apache/druid/query/aggregation/PostAggregator.java

@@ -40,6 +40,7 @@ public interface PostAggregator extends Cacheable
   @Nullable
   Object compute(Map<String, Object> combinedAggregators);
 
+  @Nullable
   String getName();
 
   /**

processing/src/main/java/org/apache/druid/query/aggregation/SerializablePairLongString.java

@@ -23,10 +23,12 @@
 import com.fasterxml.jackson.annotation.JsonProperty;
 import org.apache.druid.collections.SerializablePair;
 
+import javax.annotation.Nullable;
+
 public class SerializablePairLongString extends SerializablePair<Long, String>
 {
   @JsonCreator
-  public SerializablePairLongString(@JsonProperty("lhs") Long lhs, @JsonProperty("rhs") String rhs)
+  public SerializablePairLongString(@JsonProperty("lhs") Long lhs, @JsonProperty("rhs") @Nullable String rhs)
   {
     super(lhs, rhs);
   }

processing/src/main/java/org/apache/druid/query/aggregation/last/StringLastBufferAggregator.java

@@ -108,7 +108,7 @@ public Object get(ByteBuffer buf, int position)
     mutationBuffer.position(position);
 
     Long timeValue = mutationBuffer.getLong(position);
-    Integer stringSizeBytes = mutationBuffer.getInt(position + Long.BYTES);
+    int stringSizeBytes = mutationBuffer.getInt(position + Long.BYTES);
 
     SerializablePairLongString serializablePair;
 

processing/src/main/java/org/apache/druid/query/aggregation/post/ArithmeticPostAggregator.java

@@ -29,6 +29,8 @@
 import org.apache.druid.query.aggregation.PostAggregator;
 import org.apache.druid.query.cache.CacheKeyBuilder;
 
+import javax.annotation.Nullable;
+
 import java.util.Comparator;
 import java.util.HashMap;
 import java.util.HashSet;
@@ -71,7 +73,7 @@ public ArithmeticPostAggregator(
       @JsonProperty("name") String name,
       @JsonProperty("fn") String fnName,
       @JsonProperty("fields") List<PostAggregator> fields,
-      @JsonProperty("ordering") String ordering
+      @JsonProperty("ordering") @Nullable String ordering
   )
   {
     Preconditions.checkArgument(fnName != null, "fn cannot not be null");

processing/src/main/java/org/apache/druid/query/aggregation/post/ExpressionPostAggregator.java

@@ -74,7 +74,7 @@ public class ExpressionPostAggregator implements PostAggregator
   public ExpressionPostAggregator(
       @JsonProperty("name") String name,
       @JsonProperty("expression") String expression,
-      @JsonProperty("ordering") String ordering,
+      @JsonProperty("ordering") @Nullable String ordering,
       @JacksonInject ExprMacroTable macroTable
   )
   {