Move SearchHit and SearchHits to Writeable (#37931)

This allowed to make SearchHits immutable, while quite a few fields in
SearchHit have to stay mutable unfortunately.

Relates to #34389

modules/rank-eval/src/main/java/org/elasticsearch/index/rankeval/RatedSearchHit.java

@@ -49,8 +49,7 @@ public class RatedSearchHit implements Writeable, ToXContentObject {
     }
 
     RatedSearchHit(StreamInput in) throws IOException {
-        this(SearchHit.readSearchHit(in),
-                in.readBoolean() == true ? OptionalInt.of(in.readVInt()) : OptionalInt.empty());
+        this(new SearchHit(in), in.readBoolean() == true ? OptionalInt.of(in.readVInt()) : OptionalInt.empty());
     }
 
     @Override

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

@@ -32,7 +32,6 @@ import org.elasticsearch.common.compress.CompressorFactory;
 import org.elasticsearch.common.document.DocumentField;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
-import org.elasticsearch.common.io.stream.Streamable;
 import org.elasticsearch.common.io.stream.Writeable;
 import org.elasticsearch.common.text.Text;
 import org.elasticsearch.common.xcontent.ConstructingObjectParser;
@@ -80,17 +79,17 @@ import static org.elasticsearch.search.fetch.subphase.highlight.HighlightField.r
  *
  * @see SearchHits
  */
-public final class SearchHit implements Streamable, ToXContentObject, Iterable<DocumentField> {
+public final class SearchHit implements Writeable, ToXContentObject, Iterable<DocumentField> {
 
-    private transient int docId;
+    private final transient int docId;
 
     private static final float DEFAULT_SCORE = Float.NaN;
     private float score = DEFAULT_SCORE;
 
-    private Text id;
-    private Text type;
+    private final Text id;
+    private final Text type;
 
-    private NestedIdentity nestedIdentity;
+    private final NestedIdentity nestedIdentity;
 
     private long version = -1;
     private long seqNo = SequenceNumbers.UNASSIGNED_SEQ_NO;
@@ -98,7 +97,7 @@ public final class SearchHit implements Streamable, ToXContentObject, Iterable<D
 
     private BytesReference source;
 
-    private Map<String, DocumentField> fields = emptyMap();
+    private Map<String, DocumentField> fields;
 
     private Map<String, HighlightField> highlightFields = null;
 
@@ -121,10 +120,6 @@ public final class SearchHit implements Streamable, ToXContentObject, Iterable<D
 
     private Map<String, SearchHits> innerHits;
 
-    SearchHit() {
-
-    }
-
     //used only in tests
     public SearchHit(int docId) {
         this(docId, null, null, null);
@@ -146,6 +141,134 @@ public final class SearchHit implements Streamable, ToXContentObject, Iterable<D
         this.fields = fields;
     }
 
+    public SearchHit(StreamInput in) throws IOException {
+        docId = -1;
+        score = in.readFloat();
+        id = in.readOptionalText();
+        type = in.readOptionalText();
+        nestedIdentity = in.readOptionalWriteable(NestedIdentity::new);
+        version = in.readLong();
+        if (in.getVersion().onOrAfter(Version.V_6_7_0)) {
+            seqNo = in.readZLong();
+            primaryTerm = in.readVLong();
+        }
+        source = in.readBytesReference();
+        if (source.length() == 0) {
+            source = null;
+        }
+        if (in.readBoolean()) {
+            explanation = readExplanation(in);
+        }
+        int size = in.readVInt();
+        if (size == 0) {
+            fields = emptyMap();
+        } else if (size == 1) {
+            DocumentField hitField = DocumentField.readDocumentField(in);
+            fields = singletonMap(hitField.getName(), hitField);
+        } else {
+            Map<String, DocumentField> fields = new HashMap<>();
+            for (int i = 0; i < size; i++) {
+                DocumentField hitField = DocumentField.readDocumentField(in);
+                fields.put(hitField.getName(), hitField);
+            }
+            this.fields = unmodifiableMap(fields);
+        }
+
+        size = in.readVInt();
+        if (size == 0) {
+            highlightFields = emptyMap();
+        } else if (size == 1) {
+            HighlightField field = readHighlightField(in);
+            highlightFields = singletonMap(field.name(), field);
+        } else {
+            Map<String, HighlightField> highlightFields = new HashMap<>();
+            for (int i = 0; i < size; i++) {
+                HighlightField field = readHighlightField(in);
+                highlightFields.put(field.name(), field);
+            }
+            this.highlightFields = unmodifiableMap(highlightFields);
+        }
+
+        sortValues = new SearchSortValues(in);
+
+        size = in.readVInt();
+        if (size > 0) {
+            matchedQueries = new String[size];
+            for (int i = 0; i < size; i++) {
+                matchedQueries[i] = in.readString();
+            }
+        }
+        // we call the setter here because that also sets the local index parameter
+        shard(in.readOptionalWriteable(SearchShardTarget::new));
+        size = in.readVInt();
+        if (size > 0) {
+            innerHits = new HashMap<>(size);
+            for (int i = 0; i < size; i++) {
+                String key = in.readString();
+                SearchHits value = new SearchHits(in);
+                innerHits.put(key, value);
+            }
+        } else {
+            innerHits = null;
+        }
+    }
+
+    @Override
+    public void writeTo(StreamOutput out) throws IOException {
+        out.writeFloat(score);
+        out.writeOptionalText(id);
+        out.writeOptionalText(type);
+        out.writeOptionalWriteable(nestedIdentity);
+        out.writeLong(version);
+        if (out.getVersion().onOrAfter(Version.V_6_7_0)) {
+            out.writeZLong(seqNo);
+            out.writeVLong(primaryTerm);
+        }
+        out.writeBytesReference(source);
+        if (explanation == null) {
+            out.writeBoolean(false);
+        } else {
+            out.writeBoolean(true);
+            writeExplanation(out, explanation);
+        }
+        if (fields == null) {
+            out.writeVInt(0);
+        } else {
+            out.writeVInt(fields.size());
+            for (DocumentField hitField : getFields().values()) {
+                hitField.writeTo(out);
+            }
+        }
+        if (highlightFields == null) {
+            out.writeVInt(0);
+        } else {
+            out.writeVInt(highlightFields.size());
+            for (HighlightField highlightField : highlightFields.values()) {
+                highlightField.writeTo(out);
+            }
+        }
+        sortValues.writeTo(out);
+
+        if (matchedQueries.length == 0) {
+            out.writeVInt(0);
+        } else {
+            out.writeVInt(matchedQueries.length);
+            for (String matchedFilter : matchedQueries) {
+                out.writeString(matchedFilter);
+            }
+        }
+        out.writeOptionalWriteable(shard);
+        if (innerHits == null) {
+            out.writeVInt(0);
+        } else {
+            out.writeVInt(innerHits.size());
+            for (Map.Entry<String, SearchHits> entry : innerHits.entrySet()) {
+                out.writeString(entry.getKey());
+                entry.getValue().writeTo(out);
+            }
+        }
+    }
+
     public int docId() {
         return this.docId;
     }
@@ -771,140 +894,6 @@ public final class SearchHit implements Streamable, ToXContentObject, Iterable<D
         builder.endObject();
     }
 
-    public static SearchHit readSearchHit(StreamInput in) throws IOException {
-        SearchHit hit = new SearchHit();
-        hit.readFrom(in);
-        return hit;
-    }
-
-    @Override
-    public void readFrom(StreamInput in) throws IOException {
-        score = in.readFloat();
-        id = in.readOptionalText();
-        type = in.readOptionalText();
-        nestedIdentity = in.readOptionalWriteable(NestedIdentity::new);
-        version = in.readLong();
-        if (in.getVersion().onOrAfter(Version.V_6_7_0)) {
-            seqNo = in.readZLong();
-            primaryTerm = in.readVLong();
-        }
-        source = in.readBytesReference();
-        if (source.length() == 0) {
-            source = null;
-        }
-        if (in.readBoolean()) {
-            explanation = readExplanation(in);
-        }
-        int size = in.readVInt();
-        if (size == 0) {
-            fields = emptyMap();
-        } else if (size == 1) {
-            DocumentField hitField = DocumentField.readDocumentField(in);
-            fields = singletonMap(hitField.getName(), hitField);
-        } else {
-            Map<String, DocumentField> fields = new HashMap<>();
-            for (int i = 0; i < size; i++) {
-                DocumentField hitField = DocumentField.readDocumentField(in);
-                fields.put(hitField.getName(), hitField);
-            }
-            this.fields = unmodifiableMap(fields);
-        }
-
-        size = in.readVInt();
-        if (size == 0) {
-            highlightFields = emptyMap();
-        } else if (size == 1) {
-            HighlightField field = readHighlightField(in);
-            highlightFields = singletonMap(field.name(), field);
-        } else {
-            Map<String, HighlightField> highlightFields = new HashMap<>();
-            for (int i = 0; i < size; i++) {
-                HighlightField field = readHighlightField(in);
-                highlightFields.put(field.name(), field);
-            }
-            this.highlightFields = unmodifiableMap(highlightFields);
-        }
-
-        sortValues = new SearchSortValues(in);
-
-        size = in.readVInt();
-        if (size > 0) {
-            matchedQueries = new String[size];
-            for (int i = 0; i < size; i++) {
-                matchedQueries[i] = in.readString();
-            }
-        }
-        // we call the setter here because that also sets the local index parameter
-        shard(in.readOptionalWriteable(SearchShardTarget::new));
-        size = in.readVInt();
-        if (size > 0) {
-            innerHits = new HashMap<>(size);
-            for (int i = 0; i < size; i++) {
-                String key = in.readString();
-                SearchHits value = SearchHits.readSearchHits(in);
-                innerHits.put(key, value);
-            }
-        } else {
-            innerHits = null;
-        }
-    }
-
-    @Override
-    public void writeTo(StreamOutput out) throws IOException {
-        out.writeFloat(score);
-        out.writeOptionalText(id);
-        out.writeOptionalText(type);
-        out.writeOptionalWriteable(nestedIdentity);
-        out.writeLong(version);
-        if (out.getVersion().onOrAfter(Version.V_6_7_0)) {
-            out.writeZLong(seqNo);
-            out.writeVLong(primaryTerm);
-        }
-        out.writeBytesReference(source);
-        if (explanation == null) {
-            out.writeBoolean(false);
-        } else {
-            out.writeBoolean(true);
-            writeExplanation(out, explanation);
-        }
-        if (fields == null) {
-            out.writeVInt(0);
-        } else {
-            out.writeVInt(fields.size());
-            for (DocumentField hitField : getFields().values()) {
-                hitField.writeTo(out);
-            }
-        }
-        if (highlightFields == null) {
-            out.writeVInt(0);
-        } else {
-            out.writeVInt(highlightFields.size());
-            for (HighlightField highlightField : highlightFields.values()) {
-                highlightField.writeTo(out);
-            }
-        }
-        sortValues.writeTo(out);
-
-        if (matchedQueries.length == 0) {
-            out.writeVInt(0);
-        } else {
-            out.writeVInt(matchedQueries.length);
-            for (String matchedFilter : matchedQueries) {
-                out.writeString(matchedFilter);
-            }
-        }
-        out.writeOptionalWriteable(shard);
-        if (innerHits == null) {
-            out.writeVInt(0);
-        } else {
-            out.writeVInt(innerHits.size());
-            for (Map.Entry<String, SearchHits> entry : innerHits.entrySet()) {
-                out.writeString(entry.getKey());
-                entry.getValue().writeTo(out);
-            }
-        }
-    }
-
     @Override
     public boolean equals(Object obj) {
         if (obj == null || getClass() != obj.getClass()) {

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

@@ -26,7 +26,6 @@ import org.elasticsearch.Version;
 import org.elasticsearch.common.Nullable;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
-import org.elasticsearch.common.io.stream.Streamable;
 import org.elasticsearch.common.io.stream.Writeable;
 import org.elasticsearch.common.lucene.Lucene;
 import org.elasticsearch.common.xcontent.ToXContentFragment;
@@ -43,7 +42,7 @@ import java.util.Objects;
 
 import static org.elasticsearch.common.xcontent.XContentParserUtils.ensureExpectedToken;
 
-public final class SearchHits implements Streamable, ToXContentFragment, Iterable<SearchHit> {
+public final class SearchHits implements Writeable, ToXContentFragment, Iterable<SearchHit> {
     public static SearchHits empty() {
         return empty(true);
     }
@@ -55,22 +54,15 @@ public final class SearchHits implements Streamable, ToXContentFragment, Iterabl
 
     public static final SearchHit[] EMPTY = new SearchHit[0];
 
-    private SearchHit[] hits;
-
-    private Total totalHits;
-
-    private float maxScore;
-
+    private final SearchHit[] hits;
+    private final Total totalHits;
+    private final float maxScore;
     @Nullable
-    private SortField[] sortFields;
+    private final SortField[] sortFields;
     @Nullable
-    private String collapseField;
+    private final String collapseField;
     @Nullable
-    private Object[] collapseValues;
-
-    SearchHits() {
-
-    }
+    private final Object[] collapseValues;
 
     public SearchHits(SearchHit[] hits, @Nullable TotalHits totalHits, float maxScore) {
         this(hits, totalHits, maxScore, null, null, null);
@@ -86,6 +78,55 @@ public final class SearchHits implements Streamable, ToXContentFragment, Iterabl
         this.collapseValues = collapseValues;
     }
 
+    public SearchHits(StreamInput in) throws IOException {
+        if (in.readBoolean()) {
+            totalHits = new Total(in);
+        } else {
+            // track_total_hits is false
+            totalHits = null;
+        }
+        maxScore = in.readFloat();
+        int size = in.readVInt();
+        if (size == 0) {
+            hits = EMPTY;
+        } else {
+            hits = new SearchHit[size];
+            for (int i = 0; i < hits.length; i++) {
+                hits[i] = new SearchHit(in);
+            }
+        }
+        if (in.getVersion().onOrAfter(Version.V_6_6_0)) {
+            sortFields = in.readOptionalArray(Lucene::readSortField, SortField[]::new);
+            collapseField = in.readOptionalString();
+            collapseValues = in.readOptionalArray(Lucene::readSortValue, Object[]::new);
+        } else {
+            sortFields = null;
+            collapseField = null;
+            collapseValues = null;
+        }
+    }
+
+    @Override
+    public void writeTo(StreamOutput out) throws IOException {
+        final boolean hasTotalHits = totalHits != null;
+        out.writeBoolean(hasTotalHits);
+        if (hasTotalHits) {
+            totalHits.writeTo(out);
+        }
+        out.writeFloat(maxScore);
+        out.writeVInt(hits.length);
+        if (hits.length > 0) {
+            for (SearchHit hit : hits) {
+                hit.writeTo(out);
+            }
+        }
+        if (out.getVersion().onOrAfter(Version.V_6_6_0)) {
+            out.writeOptionalArray(Lucene::writeSortField, sortFields);
+            out.writeOptionalString(collapseField);
+            out.writeOptionalArray(Lucene::writeSortValue, collapseValues);
+        }
+    }
+
     /**
      * The total number of hits for the query or null if the tracking of total hits
      * is disabled in the request.
@@ -222,58 +263,6 @@ public final class SearchHits implements Streamable, ToXContentFragment, Iterabl
         return new SearchHits(hits.toArray(new SearchHit[0]), totalHits, maxScore);
     }
 
-    public static SearchHits readSearchHits(StreamInput in) throws IOException {
-        SearchHits hits = new SearchHits();
-        hits.readFrom(in);
-        return hits;
-    }
-
-    @Override
-    public void readFrom(StreamInput in) throws IOException {
-        if (in.readBoolean()) {
-            totalHits = new Total(in);
-        } else {
-            // track_total_hits is false
-            totalHits = null;
-        }
-        maxScore = in.readFloat();
-        int size = in.readVInt();
-        if (size == 0) {
-            hits = EMPTY;
-        } else {
-            hits = new SearchHit[size];
-            for (int i = 0; i < hits.length; i++) {
-                hits[i] = SearchHit.readSearchHit(in);
-            }
-        }
-        if (in.getVersion().onOrAfter(Version.V_6_6_0)) {
-            sortFields = in.readOptionalArray(Lucene::readSortField, SortField[]::new);
-            collapseField = in.readOptionalString();
-            collapseValues = in.readOptionalArray(Lucene::readSortValue, Object[]::new);
-        }
-    }
-
-    @Override
-    public void writeTo(StreamOutput out) throws IOException {
-        final boolean hasTotalHits = totalHits != null;
-        out.writeBoolean(hasTotalHits);
-        if (hasTotalHits) {
-            totalHits.writeTo(out);
-        }
-        out.writeFloat(maxScore);
-        out.writeVInt(hits.length);
-        if (hits.length > 0) {
-            for (SearchHit hit : hits) {
-                hit.writeTo(out);
-            }
-        }
-        if (out.getVersion().onOrAfter(Version.V_6_6_0)) {
-            out.writeOptionalArray(Lucene::writeSortField, sortFields);
-            out.writeOptionalString(collapseField);
-            out.writeOptionalArray(Lucene::writeSortValue, collapseValues);
-        }
-    }
-
     @Override
     public boolean equals(Object obj) {
         if (obj == null || getClass() != obj.getClass()) {

server/src/main/java/org/elasticsearch/search/aggregations/metrics/InternalTopHits.java

@@ -65,7 +65,7 @@ public class InternalTopHits extends InternalAggregation implements TopHits {
         from = in.readVInt();
         size = in.readVInt();
         topDocs = Lucene.readTopDocs(in);
-        searchHits = SearchHits.readSearchHits(in);
+        searchHits = new SearchHits(in);
     }
 
     @Override

server/src/main/java/org/elasticsearch/search/fetch/FetchSearchResult.java

@@ -22,9 +22,9 @@ package org.elasticsearch.search.fetch;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.search.SearchHit;
+import org.elasticsearch.search.SearchHits;
 import org.elasticsearch.search.SearchPhaseResult;
 import org.elasticsearch.search.SearchShardTarget;
-import org.elasticsearch.search.SearchHits;
 import org.elasticsearch.search.query.QuerySearchResult;
 
 import java.io.IOException;
@@ -92,7 +92,7 @@ public final class FetchSearchResult extends SearchPhaseResult {
     public void readFrom(StreamInput in) throws IOException {
         super.readFrom(in);
         requestId = in.readLong();
-        hits = SearchHits.readSearchHits(in);
+        hits = new SearchHits(in);
     }
 
     @Override

server/src/main/java/org/elasticsearch/search/internal/InternalSearchResponse.java

@@ -51,7 +51,7 @@ public class InternalSearchResponse extends SearchResponseSections implements Wr
 
     public InternalSearchResponse(StreamInput in) throws IOException {
         super(
-                SearchHits.readSearchHits(in),
+                new SearchHits(in),
                 in.readBoolean() ? InternalAggregations.readAggregations(in) : null,
                 in.readBoolean() ? new Suggest(in) : null,
                 in.readBoolean(),

server/src/main/java/org/elasticsearch/search/suggest/completion/CompletionSuggestion.java

@@ -292,7 +292,7 @@ public final class CompletionSuggestion extends Suggest.Suggestion<CompletionSug
                 super(in);
                 this.doc = Lucene.readScoreDoc(in);
                 if (in.readBoolean()) {
-                    this.hit = SearchHit.readSearchHit(in);
+                    this.hit = new SearchHit(in);
                 }
                 int contextSize = in.readInt();
                 this.contexts = new LinkedHashMap<>(contextSize);

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

@@ -27,6 +27,7 @@ import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.bytes.BytesArray;
 import org.elasticsearch.common.bytes.BytesReference;
 import org.elasticsearch.common.document.DocumentField;
+import org.elasticsearch.common.io.stream.Writeable;
 import org.elasticsearch.common.text.Text;
 import org.elasticsearch.common.xcontent.ToXContent;
 import org.elasticsearch.common.xcontent.XContentBuilder;
@@ -39,7 +40,7 @@ import org.elasticsearch.index.shard.ShardId;
 import org.elasticsearch.search.SearchHit.NestedIdentity;
 import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
 import org.elasticsearch.search.fetch.subphase.highlight.HighlightFieldTests;
-import org.elasticsearch.test.AbstractStreamableTestCase;
+import org.elasticsearch.test.AbstractWireSerializingTestCase;
 import org.elasticsearch.test.RandomObjects;
 import org.elasticsearch.test.VersionUtils;
 
@@ -59,7 +60,7 @@ import static org.hamcrest.Matchers.instanceOf;
 import static org.hamcrest.Matchers.notNullValue;
 import static org.hamcrest.Matchers.nullValue;
 
-public class SearchHitTests extends AbstractStreamableTestCase<SearchHit> {
+public class SearchHitTests extends AbstractWireSerializingTestCase<SearchHit> {
     public static SearchHit createTestItem(boolean withOptionalInnerHits, boolean withShardTarget) {
         return createTestItem(randomFrom(XContentType.values()), withOptionalInnerHits, withShardTarget);
     }
@@ -139,8 +140,8 @@ public class SearchHitTests extends AbstractStreamableTestCase<SearchHit> {
     }
 
     @Override
-    protected SearchHit createBlankInstance() {
-        return new SearchHit();
+    protected Writeable.Reader<SearchHit> instanceReader() {
+        return SearchHit::new;
     }
 
     @Override
@@ -246,7 +247,7 @@ public class SearchHitTests extends AbstractStreamableTestCase<SearchHit> {
         SearchHits hits = new SearchHits(new SearchHit[]{hit1, hit2}, new TotalHits(2, TotalHits.Relation.EQUAL_TO), 1f);
 
         Version version = VersionUtils.randomVersion(random());
-        SearchHits results = copyStreamable(hits, getNamedWriteableRegistry(), SearchHits::new, version);
+        SearchHits results = copyWriteable(hits, getNamedWriteableRegistry(), SearchHits::new, version);
         SearchShardTarget deserializedTarget = results.getAt(0).getShard();
         assertThat(deserializedTarget, equalTo(target));
         assertThat(results.getAt(0).getInnerHits().get("1").getAt(0).getShard(), notNullValue());

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

@@ -27,6 +27,7 @@ import org.elasticsearch.action.OriginalIndices;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.bytes.BytesReference;
 import org.elasticsearch.common.io.stream.StreamInput;
+import org.elasticsearch.common.io.stream.Writeable;
 import org.elasticsearch.common.lucene.LuceneTests;
 import org.elasticsearch.common.text.Text;
 import org.elasticsearch.common.xcontent.LoggingDeprecationHandler;
@@ -37,7 +38,7 @@ import org.elasticsearch.common.xcontent.XContentType;
 import org.elasticsearch.common.xcontent.json.JsonXContent;
 import org.elasticsearch.index.Index;
 import org.elasticsearch.index.shard.ShardId;
-import org.elasticsearch.test.AbstractStreamableXContentTestCase;
+import org.elasticsearch.test.AbstractSerializingTestCase;
 import org.elasticsearch.test.VersionUtils;
 
 import java.io.IOException;
@@ -45,7 +46,7 @@ import java.util.Base64;
 import java.util.Collections;
 import java.util.function.Predicate;
 
-public class SearchHitsTests extends AbstractStreamableXContentTestCase<SearchHits> {
+public class SearchHitsTests extends AbstractSerializingTestCase<SearchHits> {
 
     public static SearchHits createTestItem(boolean withOptionalInnerHits, boolean withShardTarget) {
         return createTestItem(randomFrom(XContentType.values()), withOptionalInnerHits, withShardTarget);
@@ -171,8 +172,8 @@ public class SearchHitsTests extends AbstractStreamableXContentTestCase<SearchHi
     }
 
     @Override
-    protected SearchHits createBlankInstance() {
-        return new SearchHits();
+    protected Writeable.Reader<SearchHits> instanceReader() {
+        return SearchHits::new;
     }
 
     @Override
@@ -274,8 +275,7 @@ public class SearchHitsTests extends AbstractStreamableXContentTestCase<SearchHi
     public void testReadFromPre6_6_0() throws IOException {
         try (StreamInput in = StreamInput.wrap(Base64.getDecoder().decode("AQC/gAAAAAA="))) {
             in.setVersion(VersionUtils.randomVersionBetween(random(), Version.V_6_0_0, VersionUtils.getPreviousVersion(Version.V_6_6_0)));
-            SearchHits searchHits = new SearchHits();
-            searchHits.readFrom(in);
+            SearchHits searchHits = new SearchHits(in);
             assertEquals(0, searchHits.getHits().length);
             assertNotNull(searchHits.getTotalHits());
             assertEquals(0L, searchHits.getTotalHits().value);