Add searchAfter interfaces to NativeSearchQueryBuilder.

Original Pull Request #2106 
Closes #2105

Author: owen-q

src/main/java/org/springframework/data/elasticsearch/core/query/NativeSearchQueryBuilder.java

@@ -50,6 +50,7 @@
  * @author Peter-Josef Meisch
  * @author Peer Mueller
  * @author vdisk
+ * @author owen.qq
  */
 public class NativeSearchQueryBuilder {
 
@@ -80,6 +81,7 @@ public class NativeSearchQueryBuilder {
 	@Nullable private Duration timeout;
 	private final List<RescorerQuery> rescorerQueries = new ArrayList<>();
 	@Nullable private SuggestBuilder suggestBuilder;
+	@Nullable private List<Object> searchAfter;
 
 	public NativeSearchQueryBuilder withQuery(QueryBuilder queryBuilder) {
 		this.queryBuilder = queryBuilder;
@@ -342,6 +344,15 @@ public NativeSearchQueryBuilder withSuggestBuilder(SuggestBuilder suggestBuilder
 		return this;
 	}
 
+	public NativeSearchQueryBuilder withSearchAfter(List<Object> searchAfter) {
+		if (searchAfter != null && searchAfter.isEmpty()) {
+			return this;
+		}
+
+		this.searchAfter = searchAfter;
+		return this;
+	}
+
 	public NativeSearchQuery build() {
 
 		NativeSearchQuery nativeSearchQuery = new NativeSearchQuery( //
@@ -431,6 +442,11 @@ public NativeSearchQuery build() {
 		if (suggestBuilder != null) {
 			nativeSearchQuery.setSuggestBuilder(suggestBuilder);
 		}
+
+		if (searchAfter != null) {
+			nativeSearchQuery.setSearchAfter(searchAfter);
+		}
+
 		return nativeSearchQuery;
 	}
 }

src/test/java/org/springframework/data/elasticsearch/core/query/NativeSearchQueryBuilderTests.java

@@ -0,0 +1,47 @@
+package org.springframework.data.elasticsearch.core.query;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.util.List;
+
+import org.junit.jupiter.api.Test;
+
+import com.google.common.collect.Lists;
+
+/**
+ * @author owen.qq
+ */
+public class NativeSearchQueryBuilderTests {
+
+    @Test // #2105
+    void shouldContainEffectiveSearchAfterValue() {
+        Long lastSortValue = 1L;
+        List<Object> searchAfter = Lists.newArrayList(lastSortValue);
+
+        NativeSearchQueryBuilder nativeSearchQueryBuilder = new NativeSearchQueryBuilder();
+        nativeSearchQueryBuilder.withSearchAfter(searchAfter);
+        NativeSearchQuery nativeSearchQuery = nativeSearchQueryBuilder.build();
+
+        assertThat(nativeSearchQuery.getSearchAfter()).isNotNull();
+    }
+
+    @Test // #2105
+    void shouldIgnoreNullableSearchAfterValue() {
+        List<Object> emptySearchValueByFirstSearch = null;
+        NativeSearchQueryBuilder nativeSearchQueryBuilder = new NativeSearchQueryBuilder();
+        nativeSearchQueryBuilder.withSearchAfter(emptySearchValueByFirstSearch);
+        NativeSearchQuery nativeSearchQuery = nativeSearchQueryBuilder.build();
+
+        assertThat(nativeSearchQuery.getSearchAfter()).isNull();
+    }
+
+    @Test // #2105
+    void shouldIgnoreEmptySearchAfterValue() {
+        List<Object> emptySearchValueByFirstSearch = Lists.newArrayList();
+        NativeSearchQueryBuilder nativeSearchQueryBuilder = new NativeSearchQueryBuilder();
+        nativeSearchQueryBuilder.withSearchAfter(emptySearchValueByFirstSearch);
+        NativeSearchQuery nativeSearchQuery = nativeSearchQueryBuilder.build();
+
+        assertThat(nativeSearchQuery.getSearchAfter()).isNull();
+    }
+}