Fix equals and hashCode methods for KNNQuery and KNNQueryBuilder (#1397)

Signed-off-by: panguixin <panguixin@bytedance.com>

Author: bugmakerrrrrr

CHANGELOG.md

@@ -27,6 +27,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 * Properly designate model state for actively training models when nodes crash or leave cluster [#1317](https://github.com/opensearch-project/k-NN/pull/1317)
 * Fix script score queries not getting cached [#1367](https://github.com/opensearch-project/k-NN/pull/1367)
 * Fix KNNScorer to apply boost [#1403](https://github.com/opensearch-project/k-NN/pull/1403)
+* Fix equals and hashCode methods for KNNQuery and KNNQueryBuilder [#1397](https://github.com/opensearch-project/k-NN/pull/1397)
 ### Infrastructure
 * Upgrade gradle to 8.4 [1289](https://github.com/opensearch-project/k-NN/pull/1289)
 * Refactor security testing to install from individual components [#1307](https://github.com/opensearch-project/k-NN/pull/1307)

src/main/java/org/opensearch/knn/index/query/KNNQuery.java

@@ -5,6 +5,8 @@
 
 package org.opensearch.knn.index.query;
 
+import java.util.Arrays;
+import java.util.Objects;
 import lombok.Getter;
 import lombok.Setter;
 import org.apache.lucene.search.BooleanClause;
@@ -127,7 +129,7 @@ public String toString(String field) {
 
     @Override
     public int hashCode() {
-        return field.hashCode() ^ queryVector.hashCode() ^ k;
+        return Objects.hash(field, Arrays.hashCode(queryVector), k, indexName, filterQuery);
     }
 
     @Override
@@ -136,6 +138,10 @@ public boolean equals(Object other) {
     }
 
     private boolean equalsTo(KNNQuery other) {
-        return this.field.equals(other.getField()) && this.queryVector.equals(other.getQueryVector()) && this.k == other.getK();
+        return Objects.equals(field, other.field)
+            && Arrays.equals(queryVector, other.queryVector)
+            && Objects.equals(k, other.k)
+            && Objects.equals(indexName, other.indexName)
+            && Objects.equals(filterQuery, other.filterQuery);
     }
-};
+}

src/main/java/org/opensearch/knn/index/query/KNNQueryBuilder.java

@@ -5,6 +5,7 @@
 
 package org.opensearch.knn.index.query;
 
+import java.util.Arrays;
 import lombok.extern.log4j.Log4j2;
 import org.apache.lucene.search.MatchNoDocsQuery;
 import org.opensearch.core.common.Strings;
@@ -46,7 +47,7 @@ public class KNNQueryBuilder extends AbstractQueryBuilder<KNNQueryBuilder> {
     public static final ParseField K_FIELD = new ParseField("k");
     public static final ParseField FILTER_FIELD = new ParseField("filter");
     public static final ParseField IGNORE_UNMAPPED_FIELD = new ParseField("ignore_unmapped");
-    public static int K_MAX = 10000;
+    public static final int K_MAX = 10000;
     /**
      * The name for the knn query
      */
@@ -346,12 +347,16 @@ private ModelMetadata getModelMetadataForField(KNNVectorFieldMapper.KNNVectorFie
 
     @Override
     protected boolean doEquals(KNNQueryBuilder other) {
-        return Objects.equals(fieldName, other.fieldName) && Objects.equals(vector, other.vector) && Objects.equals(k, other.k);
+        return Objects.equals(fieldName, other.fieldName)
+            && Arrays.equals(vector, other.vector)
+            && Objects.equals(k, other.k)
+            && Objects.equals(filter, other.filter)
+            && Objects.equals(ignoreUnmapped, other.ignoreUnmapped);
     }
 
     @Override
     protected int doHashCode() {
-        return Objects.hash(fieldName, vector, k);
+        return Objects.hash(fieldName, Arrays.hashCode(vector), k, filter, ignoreUnmapped);
     }
 
     @Override

src/test/java/org/opensearch/knn/index/query/KNNQueryBuilderTests.java

@@ -90,7 +90,7 @@ public void testEmptyVector() {
         expectThrows(IllegalArgumentException.class, () -> new KNNQueryBuilder(FIELD_NAME, queryVector1, K));
     }
 
-    public void testFromXcontent() throws Exception {
+    public void testFromXContent() throws Exception {
         float[] queryVector = { 1.0f, 2.0f, 3.0f, 4.0f };
         KNNQueryBuilder knnQueryBuilder = new KNNQueryBuilder(FIELD_NAME, queryVector, K);
         XContentBuilder builder = XContentFactory.jsonBuilder();
@@ -103,10 +103,10 @@ public void testFromXcontent() throws Exception {
         XContentParser contentParser = createParser(builder);
         contentParser.nextToken();
         KNNQueryBuilder actualBuilder = KNNQueryBuilder.fromXContent(contentParser);
-        actualBuilder.equals(knnQueryBuilder);
+        assertEquals(knnQueryBuilder, actualBuilder);
     }
 
-    public void testFromXcontent_WithFilter() throws Exception {
+    public void testFromXContent_WithFilter() throws Exception {
         final ClusterService clusterService = mockClusterService(Version.CURRENT);
 
         final KNNClusterUtil knnClusterUtil = KNNClusterUtil.instance();
@@ -125,7 +125,7 @@ public void testFromXcontent_WithFilter() throws Exception {
         XContentParser contentParser = createParser(builder);
         contentParser.nextToken();
         KNNQueryBuilder actualBuilder = KNNQueryBuilder.fromXContent(contentParser);
-        actualBuilder.equals(knnQueryBuilder);
+        assertEquals(knnQueryBuilder, actualBuilder);
     }
 
     public void testFromXContent_invalidQueryVectorType() throws Exception {