Replace bespoke parser for significance heuristics (#50623) (#50659)

This replaces the hand written xcontent parsers for significance
heristics with `ObjectParser` and parsing named xcontent.

As a happy accident, this was the last user of `ParseFieldRegistry` so
this PR entirely removes that class.

Closes #25519

server/src/main/java/org/elasticsearch/plugins/SearchPlugin.java

@@ -40,7 +40,6 @@ import org.elasticsearch.search.aggregations.InternalAggregation;
 import org.elasticsearch.search.aggregations.PipelineAggregationBuilder;
 import org.elasticsearch.search.aggregations.bucket.significant.SignificantTerms;
 import org.elasticsearch.search.aggregations.bucket.significant.heuristics.SignificanceHeuristic;
-import org.elasticsearch.search.aggregations.bucket.significant.heuristics.SignificanceHeuristicParser;
 import org.elasticsearch.search.aggregations.pipeline.MovAvgModel;
 import org.elasticsearch.search.aggregations.pipeline.MovAvgPipelineAggregator;
 import org.elasticsearch.search.aggregations.pipeline.PipelineAggregator;
@@ -56,6 +55,7 @@ import java.io.IOException;
 import java.util.List;
 import java.util.Map;
 import java.util.TreeMap;
+import java.util.function.BiFunction;
 
 import static java.util.Collections.emptyList;
 import static java.util.Collections.emptyMap;
@@ -74,7 +74,7 @@ public interface SearchPlugin {
      * The new {@link SignificanceHeuristic}s defined by this plugin. {@linkplain SignificanceHeuristic}s are used by the
      * {@link SignificantTerms} aggregation to pick which terms are significant for a given query.
      */
-    default List<SearchExtensionSpec<SignificanceHeuristic, SignificanceHeuristicParser>> getSignificanceHeuristics() {
+    default List<SignificanceHeuristicSpec<?>> getSignificanceHeuristics() {
         return emptyList();
     }
     /**
@@ -146,6 +146,19 @@ public interface SearchPlugin {
         }
     }
 
+    /**
+     * Specification of custom {@link SignificanceHeuristic}.
+     */
+    class SignificanceHeuristicSpec<T extends SignificanceHeuristic> extends SearchExtensionSpec<T, BiFunction<XContentParser, Void, T>> {
+        public SignificanceHeuristicSpec(ParseField name, Writeable.Reader<T> reader, BiFunction<XContentParser, Void, T> parser) {
+            super(name, reader, parser);
+        }
+
+        public SignificanceHeuristicSpec(String name, Writeable.Reader<T> reader, BiFunction<XContentParser, Void, T> parser) {
+            super(name, reader, parser);
+        }
+    }
+
     /**
      * Specification for a {@link Suggester}.
      */

server/src/main/java/org/elasticsearch/script/Script.java

@@ -27,6 +27,7 @@ import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.io.stream.Writeable;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.common.xcontent.AbstractObjectParser;
 import org.elasticsearch.common.xcontent.LoggingDeprecationHandler;
 import org.elasticsearch.common.xcontent.NamedXContentRegistry;
 import org.elasticsearch.common.xcontent.ObjectParser;
@@ -47,6 +48,9 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Objects;
+import java.util.function.BiConsumer;
+
+import static org.elasticsearch.common.xcontent.ConstructingObjectParser.constructorArg;
 
 /**
  * {@link Script} represents used-defined input that can be used to
@@ -268,6 +272,16 @@ public final class Script implements ToXContentObject, Writeable {
         PARSER.declareField(Builder::setParams, XContentParser::map, PARAMS_PARSE_FIELD, ValueType.OBJECT);
     }
 
+    /**
+     * Declare a script field on an {@link ObjectParser}.
+     * @param <T> Whatever type the {@linkplain ObjectParser} is parsing.
+     * @param parser the parser itself
+     * @param consumer the consumer for the script
+     */
+    public static <T> void declareScript(AbstractObjectParser<T, ?> parser, BiConsumer<T, Script> consumer) {
+        parser.declareField(constructorArg(), (p, c) -> Script.parse(p), Script.SCRIPT_PARSE_FIELD, ValueType.OBJECT_OR_STRING);
+    }
+
     /**
      * Convenience method to call {@link Script#parse(XContentParser, String)}
      * using the default scripting language.

server/src/main/java/org/elasticsearch/search/SearchModule.java

@@ -68,6 +68,7 @@ import org.elasticsearch.index.query.SpanContainingQueryBuilder;
 import org.elasticsearch.index.query.SpanFirstQueryBuilder;
 import org.elasticsearch.index.query.SpanMultiTermQueryBuilder;
 import org.elasticsearch.index.query.SpanNearQueryBuilder;
+import org.elasticsearch.index.query.SpanNearQueryBuilder.SpanGapQueryBuilder;
 import org.elasticsearch.index.query.SpanNotQueryBuilder;
 import org.elasticsearch.index.query.SpanOrQueryBuilder;
 import org.elasticsearch.index.query.SpanTermQueryBuilder;
@@ -97,6 +98,7 @@ import org.elasticsearch.plugins.SearchPlugin.RescorerSpec;
 import org.elasticsearch.plugins.SearchPlugin.ScoreFunctionSpec;
 import org.elasticsearch.plugins.SearchPlugin.SearchExtSpec;
 import org.elasticsearch.plugins.SearchPlugin.SearchExtensionSpec;
+import org.elasticsearch.plugins.SearchPlugin.SignificanceHeuristicSpec;
 import org.elasticsearch.plugins.SearchPlugin.SuggesterSpec;
 import org.elasticsearch.search.aggregations.AggregationBuilder;
 import org.elasticsearch.search.aggregations.AggregatorFactories;
@@ -112,8 +114,8 @@ import org.elasticsearch.search.aggregations.bucket.filter.FiltersAggregationBui
 import org.elasticsearch.search.aggregations.bucket.filter.InternalFilter;
 import org.elasticsearch.search.aggregations.bucket.filter.InternalFilters;
 import org.elasticsearch.search.aggregations.bucket.geogrid.GeoHashGridAggregationBuilder;
-import org.elasticsearch.search.aggregations.bucket.geogrid.InternalGeoHashGrid;
 import org.elasticsearch.search.aggregations.bucket.geogrid.GeoTileGridAggregationBuilder;
+import org.elasticsearch.search.aggregations.bucket.geogrid.InternalGeoHashGrid;
 import org.elasticsearch.search.aggregations.bucket.geogrid.InternalGeoTileGrid;
 import org.elasticsearch.search.aggregations.bucket.global.GlobalAggregationBuilder;
 import org.elasticsearch.search.aggregations.bucket.global.InternalGlobal;
@@ -153,7 +155,6 @@ import org.elasticsearch.search.aggregations.bucket.significant.heuristics.Mutua
 import org.elasticsearch.search.aggregations.bucket.significant.heuristics.PercentageScore;
 import org.elasticsearch.search.aggregations.bucket.significant.heuristics.ScriptHeuristic;
 import org.elasticsearch.search.aggregations.bucket.significant.heuristics.SignificanceHeuristic;
-import org.elasticsearch.search.aggregations.bucket.significant.heuristics.SignificanceHeuristicParser;
 import org.elasticsearch.search.aggregations.bucket.terms.DoubleTerms;
 import org.elasticsearch.search.aggregations.bucket.terms.LongRareTerms;
 import org.elasticsearch.search.aggregations.bucket.terms.LongTerms;
@@ -283,11 +284,10 @@ import java.util.Map;
 import java.util.function.Consumer;
 import java.util.function.Function;
 
+import static java.util.Collections.unmodifiableList;
 import static java.util.Collections.unmodifiableMap;
 import static java.util.Objects.requireNonNull;
 import static org.elasticsearch.index.query.CommonTermsQueryBuilder.COMMON_TERMS_QUERY_DEPRECATION_MSG;
-import static org.elasticsearch.index.query.SpanNearQueryBuilder.SpanGapQueryBuilder;
-import static java.util.Collections.unmodifiableList;
 
 /**
  * Sets up things that can be done at search time like queries, aggregations, and suggesters.
@@ -298,8 +298,6 @@ public class SearchModule {
 
     private final boolean transportClient;
     private final Map<String, Highlighter> highlighters;
-    private final ParseFieldRegistry<SignificanceHeuristicParser> significanceHeuristicParserRegistry = new ParseFieldRegistry<>(
-            "significance_heuristic");
     private final ParseFieldRegistry<MovAvgModel.AbstractModelParser> movingAverageModelParserRegistry = new ParseFieldRegistry<>(
             "moving_avg_model");
 
@@ -354,13 +352,6 @@ public class SearchModule {
         return highlighters;
     }
 
-    /**
-     * The registry of {@link SignificanceHeuristic}s.
-     */
-    public ParseFieldRegistry<SignificanceHeuristicParser> getSignificanceHeuristicParserRegistry() {
-        return significanceHeuristicParserRegistry;
-    }
-
     /**
      * The registry of {@link MovAvgModel}s.
      */
@@ -427,12 +418,12 @@ public class SearchModule {
                     .addResultReader(UnmappedRareTerms.NAME, UnmappedRareTerms::new)
                     .addResultReader(LongRareTerms.NAME, LongRareTerms::new));
         registerAggregation(new AggregationSpec(SignificantTermsAggregationBuilder.NAME, SignificantTermsAggregationBuilder::new,
-                SignificantTermsAggregationBuilder.getParser(significanceHeuristicParserRegistry))
+                SignificantTermsAggregationBuilder::parse)
                     .addResultReader(SignificantStringTerms.NAME, SignificantStringTerms::new)
                     .addResultReader(SignificantLongTerms.NAME, SignificantLongTerms::new)
                     .addResultReader(UnmappedSignificantTerms.NAME, UnmappedSignificantTerms::new));
         registerAggregation(new AggregationSpec(SignificantTextAggregationBuilder.NAME, SignificantTextAggregationBuilder::new,
-                SignificantTextAggregationBuilder.getParser(significanceHeuristicParserRegistry)));
+                SignificantTextAggregationBuilder::parse));
         registerAggregation(new AggregationSpec(RangeAggregationBuilder.NAME, RangeAggregationBuilder::new,
                 RangeAggregationBuilder::parse).addResultReader(InternalRange::new));
         registerAggregation(new AggregationSpec(DateRangeAggregationBuilder.NAME, DateRangeAggregationBuilder::new,
@@ -720,20 +711,22 @@ public class SearchModule {
     }
 
     private void registerSignificanceHeuristics(List<SearchPlugin> plugins) {
-        registerSignificanceHeuristic(new SearchExtensionSpec<>(ChiSquare.NAME, ChiSquare::new, ChiSquare.PARSER));
+        registerSignificanceHeuristic(new SignificanceHeuristicSpec<>(ChiSquare.NAME, ChiSquare::new, ChiSquare.PARSER));
-        registerSignificanceHeuristic(new SearchExtensionSpec<>(GND.NAME, GND::new, GND.PARSER));
+        registerSignificanceHeuristic(new SignificanceHeuristicSpec<>(GND.NAME, GND::new, GND.PARSER));
-        registerSignificanceHeuristic(new SearchExtensionSpec<>(JLHScore.NAME, JLHScore::new, JLHScore::parse));
+        registerSignificanceHeuristic(new SignificanceHeuristicSpec<>(JLHScore.NAME, JLHScore::new, JLHScore.PARSER));
-        registerSignificanceHeuristic(new SearchExtensionSpec<>(MutualInformation.NAME, MutualInformation::new, MutualInformation.PARSER));
+        registerSignificanceHeuristic(new SignificanceHeuristicSpec<>(
-        registerSignificanceHeuristic(new SearchExtensionSpec<>(PercentageScore.NAME, PercentageScore::new, PercentageScore::parse));
+            MutualInformation.NAME, MutualInformation::new, MutualInformation.PARSER));
-        registerSignificanceHeuristic(new SearchExtensionSpec<>(ScriptHeuristic.NAME, ScriptHeuristic::new, ScriptHeuristic::parse));
+        registerSignificanceHeuristic(new SignificanceHeuristicSpec<>(PercentageScore.NAME, PercentageScore::new, PercentageScore.PARSER));
+        registerSignificanceHeuristic(new SignificanceHeuristicSpec<>(ScriptHeuristic.NAME, ScriptHeuristic::new, ScriptHeuristic.PARSER));
 
         registerFromPlugin(plugins, SearchPlugin::getSignificanceHeuristics, this::registerSignificanceHeuristic);
     }
 
-    private void registerSignificanceHeuristic(SearchExtensionSpec<SignificanceHeuristic, SignificanceHeuristicParser> heuristic) {
+    private <T extends SignificanceHeuristic> void registerSignificanceHeuristic(SignificanceHeuristicSpec<?> spec) {
-        significanceHeuristicParserRegistry.register(heuristic.getParser(), heuristic.getName());
+        namedXContents.add(new NamedXContentRegistry.Entry(
-        namedWriteables.add(new NamedWriteableRegistry.Entry(SignificanceHeuristic.class, heuristic.getName().getPreferredName(),
+            SignificanceHeuristic.class, spec.getName(), p -> spec.getParser().apply(p, null)));
-                heuristic.getReader()));
+        namedWriteables.add(new NamedWriteableRegistry.Entry(
+            SignificanceHeuristic.class, spec.getName().getPreferredName(), spec.getReader()));
     }
 
     private void registerMovingAverageModels(List<SearchPlugin> plugins) {

server/src/main/java/org/elasticsearch/search/aggregations/bucket/significant/SignificantTermsAggregationBuilder.java

@@ -23,30 +23,27 @@ import org.elasticsearch.common.ParseField;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.xcontent.ObjectParser;
-import org.elasticsearch.common.xcontent.ParseFieldRegistry;
 import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.common.xcontent.XContentParser;
 import org.elasticsearch.index.query.QueryBuilder;
 import org.elasticsearch.index.query.QueryShardContext;
 import org.elasticsearch.search.aggregations.AggregationBuilder;
-import org.elasticsearch.search.aggregations.Aggregator;
 import org.elasticsearch.search.aggregations.AggregatorFactories.Builder;
 import org.elasticsearch.search.aggregations.AggregatorFactory;
 import org.elasticsearch.search.aggregations.bucket.MultiBucketAggregationBuilder;
 import org.elasticsearch.search.aggregations.bucket.significant.heuristics.JLHScore;
 import org.elasticsearch.search.aggregations.bucket.significant.heuristics.SignificanceHeuristic;
-import org.elasticsearch.search.aggregations.bucket.significant.heuristics.SignificanceHeuristicParser;
 import org.elasticsearch.search.aggregations.bucket.terms.IncludeExclude;
 import org.elasticsearch.search.aggregations.bucket.terms.TermsAggregationBuilder;
 import org.elasticsearch.search.aggregations.bucket.terms.TermsAggregator;
 import org.elasticsearch.search.aggregations.bucket.terms.TermsAggregator.BucketCountThresholds;
+import org.elasticsearch.search.aggregations.support.CoreValuesSourceType;
 import org.elasticsearch.search.aggregations.support.ValueType;
 import org.elasticsearch.search.aggregations.support.ValuesSource;
 import org.elasticsearch.search.aggregations.support.ValuesSourceAggregationBuilder;
 import org.elasticsearch.search.aggregations.support.ValuesSourceAggregatorFactory;
 import org.elasticsearch.search.aggregations.support.ValuesSourceConfig;
 import org.elasticsearch.search.aggregations.support.ValuesSourceParserHelper;
-import org.elasticsearch.search.aggregations.support.CoreValuesSourceType;
 
 import java.io.IOException;
 import java.util.Map;
@@ -65,48 +62,36 @@ public class SignificantTermsAggregationBuilder extends ValuesSourceAggregationB
             3, 0, 10, -1);
     static final SignificanceHeuristic DEFAULT_SIGNIFICANCE_HEURISTIC = new JLHScore();
 
-    public static Aggregator.Parser getParser(ParseFieldRegistry<SignificanceHeuristicParser> significanceHeuristicParserRegistry) {
+    private static final ObjectParser<SignificantTermsAggregationBuilder, Void> PARSER = new ObjectParser<>(
-        ObjectParser<SignificantTermsAggregationBuilder, Void> aggregationParser =
+        SignificantTermsAggregationBuilder.NAME,
-                new ObjectParser<>(SignificantTermsAggregationBuilder.NAME);
+        SignificanceHeuristic.class, SignificantTermsAggregationBuilder::significanceHeuristic, null);
-        ValuesSourceParserHelper.declareAnyFields(aggregationParser, true, true);
+    static {
+        ValuesSourceParserHelper.declareAnyFields(PARSER, true, true);
 
-        aggregationParser.declareInt(SignificantTermsAggregationBuilder::shardSize, TermsAggregationBuilder.SHARD_SIZE_FIELD_NAME);
+        PARSER.declareInt(SignificantTermsAggregationBuilder::shardSize, TermsAggregationBuilder.SHARD_SIZE_FIELD_NAME);
 
-        aggregationParser.declareLong(SignificantTermsAggregationBuilder::minDocCount, TermsAggregationBuilder.MIN_DOC_COUNT_FIELD_NAME);
+        PARSER.declareLong(SignificantTermsAggregationBuilder::minDocCount, TermsAggregationBuilder.MIN_DOC_COUNT_FIELD_NAME);
 
-        aggregationParser.declareLong(SignificantTermsAggregationBuilder::shardMinDocCount,
+        PARSER.declareLong(SignificantTermsAggregationBuilder::shardMinDocCount,
                 TermsAggregationBuilder.SHARD_MIN_DOC_COUNT_FIELD_NAME);
 
-        aggregationParser.declareInt(SignificantTermsAggregationBuilder::size, TermsAggregationBuilder.REQUIRED_SIZE_FIELD_NAME);
+        PARSER.declareInt(SignificantTermsAggregationBuilder::size, TermsAggregationBuilder.REQUIRED_SIZE_FIELD_NAME);
 
-        aggregationParser.declareString(SignificantTermsAggregationBuilder::executionHint,
+        PARSER.declareString(SignificantTermsAggregationBuilder::executionHint,
                 TermsAggregationBuilder.EXECUTION_HINT_FIELD_NAME);
 
-        aggregationParser.declareObject(SignificantTermsAggregationBuilder::backgroundFilter,
+        PARSER.declareObject(SignificantTermsAggregationBuilder::backgroundFilter,
                 (p, context) -> parseInnerQueryBuilder(p),
                 SignificantTermsAggregationBuilder.BACKGROUND_FILTER);
 
-        aggregationParser.declareField((b, v) -> b.includeExclude(IncludeExclude.merge(v, b.includeExclude())),
+        PARSER.declareField((b, v) -> b.includeExclude(IncludeExclude.merge(v, b.includeExclude())),
                 IncludeExclude::parseInclude, IncludeExclude.INCLUDE_FIELD, ObjectParser.ValueType.OBJECT_ARRAY_OR_STRING);
 
-        aggregationParser.declareField((b, v) -> b.includeExclude(IncludeExclude.merge(b.includeExclude(), v)),
+        PARSER.declareField((b, v) -> b.includeExclude(IncludeExclude.merge(b.includeExclude(), v)),
                 IncludeExclude::parseExclude, IncludeExclude.EXCLUDE_FIELD, ObjectParser.ValueType.STRING_ARRAY);
-
+    }
-        for (String name : significanceHeuristicParserRegistry.getNames()) {
+    public static SignificantTermsAggregationBuilder parse(String aggregationName, XContentParser parser) throws IOException {
-            aggregationParser.declareObject(SignificantTermsAggregationBuilder::significanceHeuristic,
+        return PARSER.parse(parser, new SignificantTermsAggregationBuilder(aggregationName, null), null);
-                    (p, context) -> {
-                        SignificanceHeuristicParser significanceHeuristicParser = significanceHeuristicParserRegistry
-                                .lookupReturningNullIfNotFound(name, p.getDeprecationHandler());
-                        return significanceHeuristicParser.parse(p);
-                    },
-                    new ParseField(name));
-        }
-        return new Aggregator.Parser() {
-            @Override
-            public AggregationBuilder parse(String aggregationName, XContentParser parser) throws IOException {
-                return aggregationParser.parse(parser, new SignificantTermsAggregationBuilder(aggregationName, null), null);
-            }
-        };
     }
 
     private IncludeExclude includeExclude = null;

server/src/main/java/org/elasticsearch/search/aggregations/bucket/significant/SignificantTextAggregationBuilder.java

@@ -23,7 +23,6 @@ import org.elasticsearch.common.ParseField;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.xcontent.ObjectParser;
-import org.elasticsearch.common.xcontent.ParseFieldRegistry;
 import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.common.xcontent.XContentParser;
 import org.elasticsearch.index.query.AbstractQueryBuilder;
@@ -32,11 +31,9 @@ import org.elasticsearch.index.query.QueryShardContext;
 import org.elasticsearch.search.aggregations.AbstractAggregationBuilder;
 import org.elasticsearch.search.aggregations.AggregationBuilder;
 import org.elasticsearch.search.aggregations.AggregationInitializationException;
-import org.elasticsearch.search.aggregations.Aggregator;
 import org.elasticsearch.search.aggregations.AggregatorFactories.Builder;
 import org.elasticsearch.search.aggregations.AggregatorFactory;
 import org.elasticsearch.search.aggregations.bucket.significant.heuristics.SignificanceHeuristic;
-import org.elasticsearch.search.aggregations.bucket.significant.heuristics.SignificanceHeuristicParser;
 import org.elasticsearch.search.aggregations.bucket.terms.IncludeExclude;
 import org.elasticsearch.search.aggregations.bucket.terms.TermsAggregationBuilder;
 import org.elasticsearch.search.aggregations.bucket.terms.TermsAggregator;
@@ -69,11 +66,10 @@ public class SignificantTextAggregationBuilder extends AbstractAggregationBuilde
             DEFAULT_BUCKET_COUNT_THRESHOLDS);
     private SignificanceHeuristic significanceHeuristic = DEFAULT_SIGNIFICANCE_HEURISTIC;
 
-    public static Aggregator.Parser getParser(
+    private static final ObjectParser<SignificantTextAggregationBuilder, Void> PARSER = new ObjectParser<>(
-            ParseFieldRegistry<SignificanceHeuristicParser> significanceHeuristicParserRegistry) {
+                SignificantTextAggregationBuilder.NAME,
-        ObjectParser<SignificantTextAggregationBuilder, Void> PARSER = new ObjectParser<>(
+                SignificanceHeuristic.class, SignificantTextAggregationBuilder::significanceHeuristic, null);
-                SignificantTextAggregationBuilder.NAME);
+    static {
-
         PARSER.declareInt(SignificantTextAggregationBuilder::shardSize,
                 TermsAggregationBuilder.SHARD_SIZE_FIELD_NAME);
 
@@ -105,23 +101,9 @@ public class SignificantTextAggregationBuilder extends AbstractAggregationBuilde
         PARSER.declareField((b, v) -> b.includeExclude(IncludeExclude.merge(b.includeExclude(), v)),
                 IncludeExclude::parseExclude, IncludeExclude.EXCLUDE_FIELD,
                 ObjectParser.ValueType.STRING_ARRAY);
-
+    }
-        for (String name : significanceHeuristicParserRegistry.getNames()) {
+    public static SignificantTextAggregationBuilder parse(String aggregationName, XContentParser parser) throws IOException {
-            PARSER.declareObject(SignificantTextAggregationBuilder::significanceHeuristic,
+        return PARSER.parse(parser, new SignificantTextAggregationBuilder(aggregationName, null), null);
-                    (p, context) -> {
-                        SignificanceHeuristicParser significanceHeuristicParser = significanceHeuristicParserRegistry
-                                .lookupReturningNullIfNotFound(name, p.getDeprecationHandler());
-                        return significanceHeuristicParser.parse(p);
-                    }, new ParseField(name));
-        }
-        return new Aggregator.Parser() {
-            @Override
-            public AggregationBuilder parse(String aggregationName, XContentParser parser)
-                    throws IOException {
-                return PARSER.parse(parser,
-                        new SignificantTextAggregationBuilder(aggregationName, null), null);
-            }
-        };
     }
 
     protected SignificantTextAggregationBuilder(SignificantTextAggregationBuilder clone,

server/src/main/java/org/elasticsearch/search/aggregations/bucket/significant/heuristics/ChiSquare.java

@@ -22,12 +22,18 @@ package org.elasticsearch.search.aggregations.bucket.significant.heuristics;
 
 
 import org.elasticsearch.common.io.stream.StreamInput;
+import org.elasticsearch.common.xcontent.ConstructingObjectParser;
 import org.elasticsearch.common.xcontent.XContentBuilder;
 
 import java.io.IOException;
 
 public class ChiSquare extends NXYSignificanceHeuristic {
     public static final String NAME = "chi_square";
+    public static final ConstructingObjectParser<ChiSquare, Void> PARSER = new ConstructingObjectParser<>(
+        NAME, buildFromParsedArgs(ChiSquare::new));
+    static {
+        NXYSignificanceHeuristic.declareParseFields(PARSER);
+    }
 
     public ChiSquare(boolean includeNegatives, boolean backgroundIsSuperset) {
         super(includeNegatives, backgroundIsSuperset);
@@ -84,15 +90,7 @@ public class ChiSquare extends NXYSignificanceHeuristic {
         return builder;
     }
 
-    public static final SignificanceHeuristicParser PARSER = new NXYParser() {
-        @Override
-        protected SignificanceHeuristic newHeuristic(boolean includeNegatives, boolean backgroundIsSuperset) {
-            return new ChiSquare(includeNegatives, backgroundIsSuperset);
-        }
-    };
-
     public static class ChiSquareBuilder extends NXYSignificanceHeuristic.NXYBuilder {
-
         public ChiSquareBuilder(boolean includeNegatives, boolean backgroundIsSuperset) {
             super(includeNegatives, backgroundIsSuperset);
         }

server/src/main/java/org/elasticsearch/search/aggregations/bucket/significant/heuristics/GND.java

@@ -21,17 +21,24 @@
 package org.elasticsearch.search.aggregations.bucket.significant.heuristics;
 
 
-import org.elasticsearch.ElasticsearchParseException;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
+import org.elasticsearch.common.xcontent.ConstructingObjectParser;
 import org.elasticsearch.common.xcontent.XContentBuilder;
-import org.elasticsearch.common.xcontent.XContentParser;
-import org.elasticsearch.index.query.QueryShardException;
 
 import java.io.IOException;
 
+import static org.elasticsearch.common.xcontent.ConstructingObjectParser.optionalConstructorArg;
+
 public class GND extends NXYSignificanceHeuristic {
     public static final String NAME = "gnd";
+    public static final ConstructingObjectParser<GND, Void> PARSER = new ConstructingObjectParser<>(NAME, args -> {
+        boolean backgroundIsSuperset = args[0] == null ? true : (boolean) args[0];
+        return new GND(backgroundIsSuperset);
+    });
+    static {
+        PARSER.declareBoolean(optionalConstructorArg(), BACKGROUND_IS_SUPERSET);
+    }
 
     public GND(boolean backgroundIsSuperset) {
         super(true, backgroundIsSuperset);
@@ -105,33 +112,7 @@ public class GND extends NXYSignificanceHeuristic {
         return builder;
     }
 
-    public static final SignificanceHeuristicParser PARSER = new NXYParser() {
-        @Override
-        protected SignificanceHeuristic newHeuristic(boolean includeNegatives, boolean backgroundIsSuperset) {
-            return new GND(backgroundIsSuperset);
-        }
-
-        @Override
-        public SignificanceHeuristic parse(XContentParser parser) throws IOException, QueryShardException {
-            String givenName = parser.currentName();
-            boolean backgroundIsSuperset = true;
-            XContentParser.Token token = parser.nextToken();
-            while (!token.equals(XContentParser.Token.END_OBJECT)) {
-                if (BACKGROUND_IS_SUPERSET.match(parser.currentName(), parser.getDeprecationHandler())) {
-                    parser.nextToken();
-                    backgroundIsSuperset = parser.booleanValue();
-                } else {
-                    throw new ElasticsearchParseException("failed to parse [{}] significance heuristic. unknown field [{}]",
-                            givenName, parser.currentName());
-                }
-                token = parser.nextToken();
-            }
-            return newHeuristic(true, backgroundIsSuperset);
-        }
-    };
-
     public static class GNDBuilder extends NXYBuilder {
-
         public GNDBuilder(boolean backgroundIsSuperset) {
             super(true, backgroundIsSuperset);
         }

server/src/main/java/org/elasticsearch/search/aggregations/bucket/significant/heuristics/JLHScore.java

@@ -21,17 +21,16 @@
 package org.elasticsearch.search.aggregations.bucket.significant.heuristics;
 
 
-import org.elasticsearch.ElasticsearchParseException;
+import java.io.IOException;
+
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
+import org.elasticsearch.common.xcontent.ObjectParser;
 import org.elasticsearch.common.xcontent.XContentBuilder;
-import org.elasticsearch.common.xcontent.XContentParser;
-import org.elasticsearch.index.query.QueryShardException;
-
-import java.io.IOException;
 
 public class JLHScore extends SignificanceHeuristic {
     public static final String NAME = "jlh";
+    public static final ObjectParser<JLHScore, Void> PARSER = new ObjectParser<>(NAME, JLHScore::new);
 
     public JLHScore() {
     }
@@ -103,17 +102,6 @@ public class JLHScore extends SignificanceHeuristic {
         return builder;
     }
 
-    public static SignificanceHeuristic parse(XContentParser parser)
-            throws IOException, QueryShardException {
-        // move to the closing bracket
-        if (!parser.nextToken().equals(XContentParser.Token.END_OBJECT)) {
-            throw new ElasticsearchParseException(
-                    "failed to parse [jlh] significance heuristic. expected an empty object, but found [{}] instead",
-                    parser.currentToken());
-        }
-        return new JLHScore();
-    }
-
     @Override
     public boolean equals(Object obj) {
         if (obj == null || obj.getClass() != getClass()) {

server/src/main/java/org/elasticsearch/search/aggregations/bucket/significant/heuristics/MutualInformation.java

@@ -22,12 +22,18 @@ package org.elasticsearch.search.aggregations.bucket.significant.heuristics;
 
 
 import org.elasticsearch.common.io.stream.StreamInput;
+import org.elasticsearch.common.xcontent.ConstructingObjectParser;
 import org.elasticsearch.common.xcontent.XContentBuilder;
 
 import java.io.IOException;
 
 public class MutualInformation extends NXYSignificanceHeuristic {
     public static final String NAME = "mutual_information";
+    public static final ConstructingObjectParser<MutualInformation, Void> PARSER = new ConstructingObjectParser<>(
+        NAME, buildFromParsedArgs(MutualInformation::new));
+    static {
+        NXYSignificanceHeuristic.declareParseFields(PARSER);
+    }
 
     private static final double log2 = Math.log(2.0);
 
@@ -118,15 +124,7 @@ public class MutualInformation extends NXYSignificanceHeuristic {
         return builder;
     }
 
-    public static final SignificanceHeuristicParser PARSER = new NXYParser() {
-        @Override
-        protected SignificanceHeuristic newHeuristic(boolean includeNegatives, boolean backgroundIsSuperset) {
-            return new MutualInformation(includeNegatives, backgroundIsSuperset);
-        }
-    };
-
     public static class MutualInformationBuilder extends NXYBuilder {
-
         public MutualInformationBuilder(boolean includeNegatives, boolean backgroundIsSuperset) {
             super(includeNegatives, backgroundIsSuperset);
         }

server/src/main/java/org/elasticsearch/search/aggregations/bucket/significant/heuristics/NXYSignificanceHeuristic.java

@@ -21,15 +21,17 @@
 package org.elasticsearch.search.aggregations.bucket.significant.heuristics;
 
 
-import org.elasticsearch.ElasticsearchParseException;
 import org.elasticsearch.common.ParseField;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
+import org.elasticsearch.common.xcontent.ConstructingObjectParser;
 import org.elasticsearch.common.xcontent.XContentBuilder;
-import org.elasticsearch.common.xcontent.XContentParser;
-import org.elasticsearch.index.query.QueryShardException;
 
 import java.io.IOException;
+import java.util.function.BiFunction;
+import java.util.function.Function;
+
+import static org.elasticsearch.common.xcontent.ConstructingObjectParser.optionalConstructorArg;
 
 public abstract class NXYSignificanceHeuristic extends SignificanceHeuristic {
 
@@ -160,34 +162,24 @@ public abstract class NXYSignificanceHeuristic extends SignificanceHeuristic {
                 backgroundIsSuperset);
     }
 
-    public abstract static class NXYParser implements SignificanceHeuristicParser {
+    /**
-
+     * Set up and {@linkplain ConstructingObjectParser} to accept the standard arguments for an {@linkplain NXYSignificanceHeuristic}.
-        @Override
+     */
-        public SignificanceHeuristic parse(XContentParser parser)
+    protected static void declareParseFields(ConstructingObjectParser<? extends NXYSignificanceHeuristic, ?> parser) {
-                throws IOException, QueryShardException {
+        parser.declareBoolean(optionalConstructorArg(), INCLUDE_NEGATIVES_FIELD);
-            String givenName = parser.currentName();
+        parser.declareBoolean(optionalConstructorArg(), BACKGROUND_IS_SUPERSET);
-            boolean includeNegatives = false;
-            boolean backgroundIsSuperset = true;
-            XContentParser.Token token = parser.nextToken();
-            while (!token.equals(XContentParser.Token.END_OBJECT)) {
-                if (INCLUDE_NEGATIVES_FIELD.match(parser.currentName(), parser.getDeprecationHandler())) {
-                    parser.nextToken();
-                    includeNegatives = parser.booleanValue();
-                } else if (BACKGROUND_IS_SUPERSET.match(parser.currentName(), parser.getDeprecationHandler())) {
-                    parser.nextToken();
-                    backgroundIsSuperset = parser.booleanValue();
-                } else {
-                    throw new ElasticsearchParseException("failed to parse [{}] significance heuristic. unknown field [{}]",
-                            givenName, parser.currentName());
-                }
-                token = parser.nextToken();
-            }
-            return newHeuristic(includeNegatives, backgroundIsSuperset);
-        }
-
-        protected abstract SignificanceHeuristic newHeuristic(boolean includeNegatives, boolean backgroundIsSuperset);
     }
 
+    /**
+     * Adapt a standard two argument ctor into one that consumes a {@linkplain ConstructingObjectParser}'s fields.
+     */
+    protected static <T> Function<Object[], T> buildFromParsedArgs(BiFunction<Boolean, Boolean, T> ctor) {
+        return args -> {
+            boolean includeNegatives = args[0] == null ? false : (boolean) args[0];
+            boolean backgroundIsSuperset = args[1] == null ? true : (boolean) args[1];
+            return ctor.apply(includeNegatives, backgroundIsSuperset);
+        };
+    }
 
     protected abstract static class NXYBuilder implements SignificanceHeuristicBuilder {
         protected boolean includeNegatives = true;

server/src/main/java/org/elasticsearch/search/aggregations/bucket/significant/heuristics/PercentageScore.java

@@ -24,6 +24,7 @@ package org.elasticsearch.search.aggregations.bucket.significant.heuristics;
 import org.elasticsearch.ElasticsearchParseException;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
+import org.elasticsearch.common.xcontent.ObjectParser;
 import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.common.xcontent.XContentParser;
 import org.elasticsearch.index.query.QueryShardException;
@@ -32,6 +33,7 @@ import java.io.IOException;
 
 public class PercentageScore extends SignificanceHeuristic {
     public static final String NAME = "percentage";
+    public static final ObjectParser<PercentageScore, Void> PARSER = new ObjectParser<>(NAME, PercentageScore::new);
 
     public PercentageScore() {
     }

server/src/main/java/org/elasticsearch/search/aggregations/bucket/significant/heuristics/ScriptHeuristic.java

@@ -21,13 +21,11 @@
 package org.elasticsearch.search.aggregations.bucket.significant.heuristics;
 
 
-import org.elasticsearch.ElasticsearchParseException;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
+import org.elasticsearch.common.xcontent.ConstructingObjectParser;
 import org.elasticsearch.common.xcontent.XContentBuilder;
-import org.elasticsearch.common.xcontent.XContentParser;
 import org.elasticsearch.index.query.QueryShardContext;
-import org.elasticsearch.index.query.QueryShardException;
 import org.elasticsearch.script.Script;
 import org.elasticsearch.script.SignificantTermsHeuristicScoreScript;
 import org.elasticsearch.search.aggregations.InternalAggregation;
@@ -37,8 +35,15 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.Objects;
 
+import static org.elasticsearch.common.xcontent.ConstructingObjectParser.constructorArg;
+
 public class ScriptHeuristic extends SignificanceHeuristic {
     public static final String NAME = "script_heuristic";
+    public static final ConstructingObjectParser<ScriptHeuristic, Void> PARSER = new ConstructingObjectParser<>(NAME, args ->
+        new ScriptHeuristic((Script) args[0]));
+    static {
+        Script.declareScript(PARSER, constructorArg());
+    }
 
     private final Script script;
 
@@ -153,32 +158,6 @@ public class ScriptHeuristic extends SignificanceHeuristic {
         return Objects.equals(script, other.script);
     }
 
-    public static SignificanceHeuristic parse(XContentParser parser)
-            throws IOException, QueryShardException {
-        String heuristicName = parser.currentName();
-        Script script = null;
-        XContentParser.Token token;
-        String currentFieldName = null;
-        while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
-            if (token.equals(XContentParser.Token.FIELD_NAME)) {
-                currentFieldName = parser.currentName();
-            } else {
-                if (Script.SCRIPT_PARSE_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
-                    script = Script.parse(parser);
-                } else {
-                    throw new ElasticsearchParseException("failed to parse [{}] significance heuristic. unknown object [{}]",
-                            heuristicName, currentFieldName);
-                }
-            }
-        }
-
-        if (script == null) {
-            throw new ElasticsearchParseException("failed to parse [{}] significance heuristic. no script found in script_heuristic",
-                    heuristicName);
-        }
-        return new ScriptHeuristic(script);
-    }
-
     public final class LongAccessor extends Number {
         public long value;
         @Override

server/src/main/java/org/elasticsearch/search/aggregations/bucket/significant/heuristics/SignificanceHeuristicParser.java

@@ -1,34 +0,0 @@
-/*
- * Licensed to Elasticsearch under one or more contributor
- * license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright
- * ownership. Elasticsearch 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.elasticsearch.search.aggregations.bucket.significant.heuristics;
-
-import org.elasticsearch.common.ParsingException;
-import org.elasticsearch.common.xcontent.XContentParser;
-
-import java.io.IOException;
-
-/**
- * Parses {@link SignificanceHeuristic}s from an {@link XContentParser}.
- */
-@FunctionalInterface
-public interface SignificanceHeuristicParser {
-    SignificanceHeuristic parse(XContentParser parser) throws IOException, ParsingException;
-}

server/src/test/java/org/elasticsearch/search/SearchModuleTests.java

@@ -40,8 +40,6 @@ import org.elasticsearch.search.aggregations.BaseAggregationBuilder;
 import org.elasticsearch.search.aggregations.InternalAggregation;
 import org.elasticsearch.search.aggregations.InternalAggregation.ReduceContext;
 import org.elasticsearch.search.aggregations.bucket.significant.heuristics.ChiSquare;
-import org.elasticsearch.search.aggregations.bucket.significant.heuristics.SignificanceHeuristic;
-import org.elasticsearch.search.aggregations.bucket.significant.heuristics.SignificanceHeuristicParser;
 import org.elasticsearch.search.aggregations.bucket.terms.TermsAggregationBuilder;
 import org.elasticsearch.search.aggregations.pipeline.AbstractPipelineAggregationBuilder;
 import org.elasticsearch.search.aggregations.pipeline.DerivativePipelineAggregationBuilder;
@@ -122,8 +120,8 @@ public class SearchModuleTests extends ESTestCase {
 
         SearchPlugin registersDupeSignificanceHeuristic = new SearchPlugin() {
             @Override
-            public List<SearchExtensionSpec<SignificanceHeuristic, SignificanceHeuristicParser>> getSignificanceHeuristics() {
+            public List<SignificanceHeuristicSpec<?>> getSignificanceHeuristics() {
-                return singletonList(new SearchExtensionSpec<>(ChiSquare.NAME, ChiSquare::new, ChiSquare.PARSER));
+                return singletonList(new SignificanceHeuristicSpec<>(ChiSquare.NAME, ChiSquare::new, ChiSquare.PARSER));
             }
         };
         expectThrows(IllegalArgumentException.class, registryForPlugin(registersDupeSignificanceHeuristic));

server/src/test/java/org/elasticsearch/search/aggregations/bucket/SignificantTermsSignificanceScoreIT.java

@@ -25,14 +25,13 @@ import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.common.xcontent.ObjectParser;
 import org.elasticsearch.common.xcontent.ToXContent;
 import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.common.xcontent.XContentFactory;
-import org.elasticsearch.common.xcontent.XContentParser;
 import org.elasticsearch.common.xcontent.XContentType;
 import org.elasticsearch.index.query.QueryBuilder;
 import org.elasticsearch.index.query.QueryBuilders;
-import org.elasticsearch.index.query.QueryShardException;
 import org.elasticsearch.plugins.Plugin;
 import org.elasticsearch.plugins.SearchPlugin;
 import org.elasticsearch.script.MockScriptPlugin;
@@ -49,7 +48,6 @@ import org.elasticsearch.search.aggregations.bucket.significant.heuristics.GND;
 import org.elasticsearch.search.aggregations.bucket.significant.heuristics.MutualInformation;
 import org.elasticsearch.search.aggregations.bucket.significant.heuristics.ScriptHeuristic;
 import org.elasticsearch.search.aggregations.bucket.significant.heuristics.SignificanceHeuristic;
-import org.elasticsearch.search.aggregations.bucket.significant.heuristics.SignificanceHeuristicParser;
 import org.elasticsearch.search.aggregations.bucket.terms.StringTerms;
 import org.elasticsearch.search.aggregations.bucket.terms.Terms;
 import org.elasticsearch.test.ESIntegTestCase;
@@ -178,9 +176,8 @@ public class SignificantTermsSignificanceScoreIT extends ESIntegTestCase {
 
     public static class CustomSignificanceHeuristicPlugin extends MockScriptPlugin implements SearchPlugin {
         @Override
-        public List<SearchExtensionSpec<SignificanceHeuristic, SignificanceHeuristicParser>> getSignificanceHeuristics() {
+        public List<SignificanceHeuristicSpec<?>> getSignificanceHeuristics() {
-            return singletonList(new SearchExtensionSpec<SignificanceHeuristic, SignificanceHeuristicParser>(SimpleHeuristic.NAME,
+            return singletonList(new SignificanceHeuristicSpec<>(SimpleHeuristic.NAME, SimpleHeuristic::new, SimpleHeuristic.PARSER));
-                    SimpleHeuristic::new, (parser) -> SimpleHeuristic.parse(parser)));
         }
 
         @Override
@@ -214,6 +211,7 @@ public class SignificantTermsSignificanceScoreIT extends ESIntegTestCase {
 
     public static class SimpleHeuristic extends SignificanceHeuristic {
         public static final String NAME = "simple";
+        public static final ObjectParser<SimpleHeuristic, Void> PARSER = new ObjectParser<>(NAME, SimpleHeuristic::new);
 
         public SimpleHeuristic() {
         }
@@ -268,12 +266,6 @@ public class SignificantTermsSignificanceScoreIT extends ESIntegTestCase {
         public double getScore(long subsetFreq, long subsetSize, long supersetFreq, long supersetSize) {
             return subsetFreq / subsetSize > supersetFreq / supersetSize ? 2.0 : 1.0;
         }
-
-        public static SignificanceHeuristic parse(XContentParser parser)
-                throws IOException, QueryShardException {
-            parser.nextToken();
-            return new SimpleHeuristic();
-        }
     }
 
     public void testXContentResponse() throws Exception {

server/src/test/java/org/elasticsearch/search/aggregations/bucket/significant/SignificanceHeuristicTests.java

@@ -28,7 +28,7 @@ import org.elasticsearch.common.io.stream.NamedWriteableRegistry;
 import org.elasticsearch.common.io.stream.OutputStreamStreamOutput;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.settings.Settings;
-import org.elasticsearch.common.xcontent.ParseFieldRegistry;
+import org.elasticsearch.common.xcontent.NamedXContentRegistry;
 import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.common.xcontent.XContentFactory;
 import org.elasticsearch.common.xcontent.XContentParseException;
@@ -46,7 +46,6 @@ import org.elasticsearch.search.aggregations.bucket.significant.heuristics.JLHSc
 import org.elasticsearch.search.aggregations.bucket.significant.heuristics.MutualInformation;
 import org.elasticsearch.search.aggregations.bucket.significant.heuristics.PercentageScore;
 import org.elasticsearch.search.aggregations.bucket.significant.heuristics.SignificanceHeuristic;
-import org.elasticsearch.search.aggregations.bucket.significant.heuristics.SignificanceHeuristicParser;
 import org.elasticsearch.search.aggregations.pipeline.PipelineAggregator;
 import org.elasticsearch.test.ESTestCase;
 import org.elasticsearch.test.TestSearchContext;
@@ -218,81 +217,62 @@ public class SignificanceHeuristicTests extends ESTestCase {
     // 1. The output of the builders can actually be parsed
     // 2. The parser does not swallow parameters after a significance heuristic was defined
     public void testBuilderAndParser() throws Exception {
-        SearchModule searchModule = new SearchModule(Settings.EMPTY, false, emptyList());
-        ParseFieldRegistry<SignificanceHeuristicParser> heuristicParserMapper = searchModule.getSignificanceHeuristicParserRegistry();
-
         // test jlh with string
-        assertTrue(parseFromString(heuristicParserMapper, "\"jlh\":{}") instanceof JLHScore);
+        assertTrue(parseFromString("\"jlh\":{}") instanceof JLHScore);
         // test gnd with string
-        assertTrue(parseFromString(heuristicParserMapper, "\"gnd\":{}") instanceof GND);
+        assertTrue(parseFromString("\"gnd\":{}") instanceof GND);
         // test mutual information with string
         boolean includeNegatives = randomBoolean();
         boolean backgroundIsSuperset = randomBoolean();
         String mutual = "\"mutual_information\":{\"include_negatives\": " + includeNegatives + ", \"background_is_superset\":"
                 + backgroundIsSuperset + "}";
         assertEquals(new MutualInformation(includeNegatives, backgroundIsSuperset),
-                parseFromString(heuristicParserMapper, mutual));
+                parseFromString(mutual));
         String chiSquare = "\"chi_square\":{\"include_negatives\": " + includeNegatives + ", \"background_is_superset\":"
                 + backgroundIsSuperset + "}";
         assertEquals(new ChiSquare(includeNegatives, backgroundIsSuperset),
-                parseFromString(heuristicParserMapper, chiSquare));
+                parseFromString(chiSquare));
 
         // test with builders
-        assertThat(parseFromBuilder(heuristicParserMapper, new JLHScore()), instanceOf(JLHScore.class));
+        assertThat(parseFromBuilder(new JLHScore()), instanceOf(JLHScore.class));
-        assertThat(parseFromBuilder(heuristicParserMapper, new GND(backgroundIsSuperset)), instanceOf(GND.class));
+        assertThat(parseFromBuilder(new GND(backgroundIsSuperset)), instanceOf(GND.class));
         assertEquals(new MutualInformation(includeNegatives, backgroundIsSuperset),
-                parseFromBuilder(heuristicParserMapper, new MutualInformation(includeNegatives, backgroundIsSuperset)));
+                parseFromBuilder(new MutualInformation(includeNegatives, backgroundIsSuperset)));
         assertEquals(new ChiSquare(includeNegatives, backgroundIsSuperset),
-                parseFromBuilder(heuristicParserMapper, new ChiSquare(includeNegatives, backgroundIsSuperset)));
+                parseFromBuilder(new ChiSquare(includeNegatives, backgroundIsSuperset)));
 
         // test exceptions
-        String faultyHeuristicdefinition = "\"mutual_information\":{\"include_negatives\": false, \"some_unknown_field\": false}";
+        String expectedError = "unknown field [unknown_field]";
-        String expectedError = "unknown field [some_unknown_field]";
+        checkParseException("\"mutual_information\":{\"include_negatives\": false, \"unknown_field\": false}", expectedError);
-        checkParseException(heuristicParserMapper, faultyHeuristicdefinition, expectedError);
+        checkParseException("\"chi_square\":{\"unknown_field\": true}", expectedError);
-
+        checkParseException("\"jlh\":{\"unknown_field\": true}", expectedError);
-        faultyHeuristicdefinition = "\"chi_square\":{\"unknown_field\": true}";
+        checkParseException("\"gnd\":{\"unknown_field\": true}", expectedError);
-        expectedError = "unknown field [unknown_field]";
-        checkParseException(heuristicParserMapper, faultyHeuristicdefinition, expectedError);
-
-        faultyHeuristicdefinition = "\"jlh\":{\"unknown_field\": true}";
-        expectedError = "expected an empty object, but found ";
-        checkParseException(heuristicParserMapper, faultyHeuristicdefinition, expectedError);
-
-        faultyHeuristicdefinition = "\"gnd\":{\"unknown_field\": true}";
-        expectedError = "unknown field [unknown_field]";
-        checkParseException(heuristicParserMapper, faultyHeuristicdefinition, expectedError);
     }
 
-    protected void checkParseException(ParseFieldRegistry<SignificanceHeuristicParser> significanceHeuristicParserRegistry,
+    protected void checkParseException(String faultyHeuristicDefinition, String expectedError) throws IOException {
-            String faultyHeuristicDefinition, String expectedError) throws IOException {
 
         try (XContentParser stParser = createParser(JsonXContent.jsonXContent,
                     "{\"field\":\"text\", " + faultyHeuristicDefinition + ",\"min_doc_count\":200}")) {
             stParser.nextToken();
-            SignificantTermsAggregationBuilder.getParser(significanceHeuristicParserRegistry).parse("testagg", stParser);
+            SignificantTermsAggregationBuilder.parse("testagg", stParser);
             fail();
         } catch (XContentParseException e) {
-            assertThat(e.getCause().getMessage(), containsString(expectedError));
+            assertThat(e.getMessage(), containsString(expectedError));
         }
     }
 
-    protected SignificanceHeuristic parseFromBuilder(ParseFieldRegistry<SignificanceHeuristicParser> significanceHeuristicParserRegistry,
+    protected SignificanceHeuristic parseFromBuilder(SignificanceHeuristic significanceHeuristic) throws IOException {
-            SignificanceHeuristic significanceHeuristic) throws IOException {
         SignificantTermsAggregationBuilder stBuilder = significantTerms("testagg");
         stBuilder.significanceHeuristic(significanceHeuristic).field("text").minDocCount(200);
         XContentBuilder stXContentBuilder = XContentFactory.jsonBuilder();
         stBuilder.internalXContent(stXContentBuilder, null);
         XContentParser stParser = createParser(JsonXContent.jsonXContent, Strings.toString(stXContentBuilder));
-        return parseSignificanceHeuristic(significanceHeuristicParserRegistry, stParser);
+        return parseSignificanceHeuristic(stParser);
     }
 
-    private static SignificanceHeuristic parseSignificanceHeuristic(
+    private static SignificanceHeuristic parseSignificanceHeuristic(XContentParser stParser) throws IOException {
-            ParseFieldRegistry<SignificanceHeuristicParser> significanceHeuristicParserRegistry,
-            XContentParser stParser) throws IOException {
         stParser.nextToken();
-        SignificantTermsAggregationBuilder aggregatorFactory =
+        SignificantTermsAggregationBuilder aggregatorFactory = SignificantTermsAggregationBuilder.parse("testagg", stParser);
-                (SignificantTermsAggregationBuilder) SignificantTermsAggregationBuilder.getParser(
-                significanceHeuristicParserRegistry).parse("testagg", stParser);
         stParser.nextToken();
         assertThat(aggregatorFactory.getBucketCountThresholds().getMinDocCount(), equalTo(200L));
         assertThat(stParser.currentToken(), equalTo(null));
@@ -300,11 +280,10 @@ public class SignificanceHeuristicTests extends ESTestCase {
         return aggregatorFactory.significanceHeuristic();
     }
 
-    protected SignificanceHeuristic parseFromString(ParseFieldRegistry<SignificanceHeuristicParser> significanceHeuristicParserRegistry,
+    protected SignificanceHeuristic parseFromString(String heuristicString) throws IOException {
-            String heuristicString) throws IOException {
         try (XContentParser stParser = createParser(JsonXContent.jsonXContent,
                 "{\"field\":\"text\", " + heuristicString + ", \"min_doc_count\":200}")) {
-            return parseSignificanceHeuristic(significanceHeuristicParserRegistry, stParser);
+            return parseSignificanceHeuristic(stParser);
         }
     }
 
@@ -494,4 +473,9 @@ public class SignificanceHeuristicTests extends ESTestCase {
         gnd = new GND(false);
         assertThat(gnd.getScore(0, 0, 0, 0), equalTo(0.0));
     }
+
+    @Override
+    protected NamedXContentRegistry xContentRegistry() {
+        return new NamedXContentRegistry(new SearchModule(Settings.EMPTY, false, emptyList()).getNamedXContents());
+    }
 }