Upgrade Elasticsearch client to 9.4.1.

Closes #3288

Signed-off-by: Peter-Josef Meisch <pj.meisch@sothawo.com>

pom.xml

@@ -5,12 +5,12 @@
 
 	<groupId>org.springframework.data</groupId>
 	<artifactId>spring-data-elasticsearch</artifactId>
-	<version>6.1.0-M2</version>
+	<version>6.1.0-SNAPSHOT</version>
 
 	<parent>
 		<groupId>org.springframework.data.build</groupId>
 		<artifactId>spring-data-parent</artifactId>
-		<version>4.1.0-M2</version>
+		<version>4.1.0-SNAPSHOT</version>
 	</parent>
 
 	<name>Spring Data Elasticsearch</name>
@@ -18,14 +18,14 @@
 	<url>https://github.com/spring-projects/spring-data-elasticsearch</url>
 
 	<properties>
-		<springdata.commons>4.1.0-M2</springdata.commons>
+		<springdata.commons>4.1.0-SNAPSHOT</springdata.commons>
 
 		<!-- version of the ElasticsearchClient	-->
-		<elasticsearch-java>9.3.1</elasticsearch-java>
-		<elasticsearch-rest-client>9.3.1</elasticsearch-rest-client>
+		<elasticsearch-java>9.4.1</elasticsearch-java>
+		<elasticsearch-rest-client>9.4.1</elasticsearch-rest-client>
 
 		<hoverfly>0.20.2</hoverfly>
-		<log4j>2.25.3</log4j>
+		<log4j>2.25.4</log4j>
 		<jsonassert>1.5.3</jsonassert>
 		<wiremock>3.9.2</wiremock>
 
@@ -499,8 +499,20 @@
 	</profiles>
 
 	<repositories>
-		
-		
+		<repository>
+			<id>spring-snapshot</id>
+			<url>https://repo.spring.io/snapshot</url>
+			<snapshots>
+				<enabled>true</enabled>
+			</snapshots>
+			<releases>
+				<enabled>false</enabled>
+			</releases>
+		</repository>
+		<repository>
+			<id>spring-milestone</id>
+			<url>https://repo.spring.io/milestone</url>
+		</repository>
 	</repositories>
 
 </project>

src/main/antora/modules/ROOT/pages/elasticsearch/elasticsearch-new.adoc

@@ -4,7 +4,7 @@
 [[new-features.6-1-0]]
 == New in Spring Data Elasticsearch 6.1
 
-* Upgrade to Elasticsearch 9.3.1
+* Upgrade to Elasticsearch 9.4.1
 * Add support to use `IndexCoordinates` as repository query parameter
 * Add support for includeNamedQueriesScore in Query
 * Add support for Micrometer observation.

src/main/antora/modules/ROOT/pages/elasticsearch/versions.adoc

@@ -6,10 +6,10 @@ The following table shows the Elasticsearch and Spring versions that are used by
 [cols="^,^,^,^",options="header"]
 |===
 | Spring Data Release Train | Spring Data Elasticsearch | Elasticsearch | Spring Framework
-| 2026.0 | 6.1.x | 9.3.1 | 7.0.x
+| 2026.0 | 6.1.x | 9.4.1 | 7.0.x
 | 2025.1 | 6.0.x | 9.2.2 | 7.0.x
-| 2025.0 | 5.5.x | 8.18.1 | 6.2.x
-| 2024.1 | 5.4.xfootnote:oom[Out of maintenance] | 8.15.5 | 6.1.x
+| 2025.0 | 5.5.xfootnote:oom[Out of maintenance] | 8.18.1 | 6.2.x
+| 2024.1 | 5.4.xfootnote:oom[] | 8.15.5 | 6.1.x
 | 2024.0 | 5.3.xfootnote:oom[] | 8.13.4 | 6.1.x
 | 2023.1 (Vaughan) | 5.2.xfootnote:oom[] | 8.11.1 | 6.1.x
 | 2023.0 (Ullmann) | 5.1.xfootnote:oom[] | 8.7.1 | 6.0.x

src/main/antora/modules/ROOT/pages/repositories/projections.adoc

@@ -1,4 +1,13 @@
 [[elasticsearch.projections]]
 = Projections
 
+[[elasticsearch.projections.limitations]]
+== Spring Data Elasticsearch Projection Limitations
+
+This chapter is pulled in from the Spring Data Commons documentation, but does not apply to Spring Data Elasticsearch.
+
+IMPORTANT: Interface-based projections are not supported in Spring Data Elasticsearch repository query methods.
+
+To limit the fields returned from Elasticsearch, use the xref:elasticsearch/repositories/elasticsearch-repositories.adoc#elasticsearch.repositories.annotations.sourcefilters[`@SourceFilters`] annotation on your repository methods instead.
+
 include::{commons}@data-commons::page$repositories/projections.adoc[leveloffset=+1]

src/main/java/org/springframework/data/elasticsearch/BulkFailureException.java

@@ -15,10 +15,11 @@
  */
 package org.springframework.data.elasticsearch;
 
-import org.springframework.dao.DataRetrievalFailureException;
-
 import java.util.Map;
 
+import org.jspecify.annotations.Nullable;
+import org.springframework.dao.DataRetrievalFailureException;
+
 /**
  * @author Peter-Josef Meisch
  * @author Illia Ulianov
@@ -42,6 +43,6 @@ public class BulkFailureException extends DataRetrievalFailureException {
 	 * @author Illia Ulianov
 	 * @since 5.2
 	 */
-	public record FailureDetails(Integer status, String errorMessage) {
+	public record FailureDetails(Integer status, @Nullable String errorMessage) {
 	}
 }

src/main/java/org/springframework/data/elasticsearch/ElasticsearchErrorCause.java

@@ -28,7 +28,7 @@ import org.jspecify.annotations.Nullable;
 public class ElasticsearchErrorCause {
 	@Nullable private final String type;
 
-	private final String reason;
+	@Nullable private final String reason;
 
 	@Nullable private final String stackTrace;
 
@@ -38,7 +38,7 @@ public class ElasticsearchErrorCause {
 
 	private final List<ElasticsearchErrorCause> suppressed;
 
-	public ElasticsearchErrorCause(@Nullable String type, String reason, @Nullable String stackTrace,
+	public ElasticsearchErrorCause(@Nullable String type, @Nullable String reason, @Nullable String stackTrace,
 			@Nullable ElasticsearchErrorCause causedBy, List<ElasticsearchErrorCause> rootCause,
 			List<ElasticsearchErrorCause> suppressed) {
 		this.type = type;
@@ -54,7 +54,7 @@ public class ElasticsearchErrorCause {
 		return type;
 	}
 
-	public String getReason() {
+	public @Nullable String getReason() {
 		return reason;
 	}
 

src/main/java/org/springframework/data/elasticsearch/annotations/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.annotations;

src/main/java/org/springframework/data/elasticsearch/aot/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.aot;

src/main/java/org/springframework/data/elasticsearch/client/elc/DocumentAdapters.java

@@ -24,6 +24,14 @@ import co.elastic.clients.elasticsearch.core.search.Hit;
 import co.elastic.clients.elasticsearch.core.search.NestedIdentity;
 import co.elastic.clients.json.JsonData;
 import co.elastic.clients.json.JsonpMapper;
+
+import java.util.Collections;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.jspecify.annotations.Nullable;
@@ -36,13 +44,6 @@ import org.springframework.data.elasticsearch.core.document.SearchDocumentAdapte
 import org.springframework.data.elasticsearch.core.document.SearchDocumentResponse;
 import org.springframework.util.Assert;
 
-import java.util.Collections;
-import java.util.LinkedHashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.function.Function;
-import java.util.stream.Collectors;
-
 /**
  * Utility class to adapt different Elasticsearch responses to a
  * {@link org.springframework.data.elasticsearch.core.document.Document}
@@ -54,188 +55,187 @@ import java.util.stream.Collectors;
  */
 final class DocumentAdapters {
 
-    private static final Log LOGGER = LogFactory.getLog(DocumentAdapters.class);
+	private static final Log LOGGER = LogFactory.getLog(DocumentAdapters.class);
 
-    private DocumentAdapters() {
-    }
+	private DocumentAdapters() {}
 
-    /**
-     * Creates a {@link SearchDocument} from a {@link Hit} returned by the Elasticsearch client.
-     *
-     * @param hit         the hit object
-     * @param jsonpMapper to map JsonData objects
-     * @return the created {@link SearchDocument}
-     */
-    public static SearchDocument from(Hit<?> hit, JsonpMapper jsonpMapper) {
+	/**
+	 * Creates a {@link SearchDocument} from a {@link Hit} returned by the Elasticsearch client.
+	 *
+	 * @param hit the hit object
+	 * @param jsonpMapper to map JsonData objects
+	 * @return the created {@link SearchDocument}
+	 */
+	public static SearchDocument from(Hit<?> hit, JsonpMapper jsonpMapper) {
 
-        Assert.notNull(hit, "hit must not be null");
+		Assert.notNull(hit, "hit must not be null");
 
-        Map<String, List<String>> highlightFields = hit.highlight();
+		Map<String, List<String>> highlightFields = hit.highlight();
 
-        Map<String, SearchDocumentResponse> innerHits = new LinkedHashMap<>();
-        hit.innerHits().forEach((name, innerHitsResult) -> {
-            // noinspection ReturnOfNull
-            innerHits.put(name, SearchDocumentResponseBuilder.from(innerHitsResult.hits(), null, null, null, 0, null, null,
-                    searchDocument -> null, jsonpMapper));
-        });
+		Map<String, SearchDocumentResponse> innerHits = new LinkedHashMap<>();
+		hit.innerHits().forEach((name, innerHitsResult) -> {
+			// noinspection ReturnOfNull
+			innerHits.put(name, SearchDocumentResponseBuilder.from(innerHitsResult.hits(), null, null, null, 0, null, null,
+					searchDocument -> null, jsonpMapper));
+		});
 
-        NestedMetaData nestedMetaData = from(hit.nested());
+		NestedMetaData nestedMetaData = from(hit.nested());
 
-        Explanation explanation = from(hit.explanation());
+		Explanation explanation = from(hit.explanation());
 
-        Map<String, Double> matchedQueries = hit.matchedQueries();
+		Map<String, Double> matchedQueries = hit.matchedQueries();
 
-        Function<Map<String, JsonData>, EntityAsMap> fromFields = fields -> {
-            StringBuilder sb = new StringBuilder("{");
-            final boolean[] firstField = {true};
-            hit.fields().forEach((key, jsonData) -> {
-                if (!firstField[0]) {
-                    sb.append(',');
-                }
-                sb.append('"').append(key).append("\":") //
-                        .append(jsonData.toJson(jsonpMapper).toString());
-                firstField[0] = false;
-            });
-            sb.append('}');
-            return new EntityAsMap().fromJson(sb.toString());
-        };
+		Function<Map<String, JsonData>, EntityAsMap> fromFields = fields -> {
+			StringBuilder sb = new StringBuilder("{");
+			final boolean[] firstField = { true };
+			hit.fields().forEach((key, jsonData) -> {
+				if (!firstField[0]) {
+					sb.append(',');
+				}
+				sb.append('"').append(key).append("\":") //
+						.append(jsonData.toJson(jsonpMapper).toString());
+				firstField[0] = false;
+			});
+			sb.append('}');
+			return new EntityAsMap().fromJson(sb.toString());
+		};
 
-        EntityAsMap hitFieldsAsMap = fromFields.apply(hit.fields());
+		EntityAsMap hitFieldsAsMap = fromFields.apply(hit.fields());
 
-        Map<String, List<Object>> documentFields = new LinkedHashMap<>();
-        hitFieldsAsMap.forEach((key, value) -> {
-            if (value instanceof List) {
-                // noinspection unchecked
-                documentFields.put(key, (List<Object>) value);
-            } else {
-                documentFields.put(key, Collections.singletonList(value));
-            }
-        });
+		Map<String, List<@Nullable Object>> documentFields = new LinkedHashMap<>();
+		hitFieldsAsMap.forEach((key, value) -> {
+			if (value instanceof List) {
+				// noinspection unchecked
+				documentFields.put(key, (List<Object>) value);
+			} else {
+				documentFields.put(key, Collections.singletonList(value));
+			}
+		});
 
-        Document document;
-        Object source = hit.source();
-        if (source == null) {
-            document = Document.from(hitFieldsAsMap);
-        } else {
-            if (source instanceof EntityAsMap entityAsMap) {
-                document = Document.from(entityAsMap);
-            } else if (source instanceof JsonData jsonData) {
-                document = Document.from(jsonData.to(EntityAsMap.class));
-            } else {
+		Document document;
+		Object source = hit.source();
+		if (source == null) {
+			document = Document.from(hitFieldsAsMap);
+		} else {
+			if (source instanceof EntityAsMap entityAsMap) {
+				document = Document.from(entityAsMap);
+			} else if (source instanceof JsonData jsonData) {
+				document = Document.from(jsonData.to(EntityAsMap.class));
+			} else {
 
-                if (LOGGER.isWarnEnabled()) {
-                    LOGGER.warn(String.format("Cannot map from type " + source.getClass().getName()));
-                }
-                document = Document.create();
-            }
-        }
-        document.setIndex(hit.index());
-        document.setId(hit.id());
+				if (LOGGER.isWarnEnabled()) {
+					LOGGER.warn(String.format("Cannot map from type " + source.getClass().getName()));
+				}
+				document = Document.create();
+			}
+		}
+		document.setIndex(hit.index());
+		document.setId(hit.id());
 
-        if (hit.version() != null) {
-            document.setVersion(hit.version());
-        }
-        document.setSeqNo(hit.seqNo() != null && hit.seqNo() >= 0 ? hit.seqNo() : -2); // -2 was the default value in the
-        // old client
-        document.setPrimaryTerm(hit.primaryTerm() != null && hit.primaryTerm() > 0 ? hit.primaryTerm() : 0);
+		if (hit.version() != null) {
+			document.setVersion(hit.version());
+		}
+		document.setSeqNo(hit.seqNo() != null && hit.seqNo() >= 0 ? hit.seqNo() : -2); // -2 was the default value in the
+		// old client
+		document.setPrimaryTerm(hit.primaryTerm() != null && hit.primaryTerm() > 0 ? hit.primaryTerm() : 0);
 
-        float score = hit.score() != null ? hit.score().floatValue() : Float.NaN;
-        return new SearchDocumentAdapter(document, score, hit.sort().stream().map(TypeUtils::toObject).toArray(),
-                documentFields, highlightFields, innerHits, nestedMetaData, explanation, matchedQueries, hit.routing());
-    }
+		float score = hit.score() != null ? hit.score().floatValue() : Float.NaN;
+		return new SearchDocumentAdapter(document, score, hit.sort().stream().map(TypeUtils::toObject).toArray(),
+				documentFields, highlightFields, innerHits, nestedMetaData, explanation, matchedQueries, hit.routing());
+	}
 
-    public static SearchDocument from(CompletionSuggestOption<EntityAsMap> completionSuggestOption) {
+	public static SearchDocument from(CompletionSuggestOption<EntityAsMap> completionSuggestOption) {
 
-        Document document = completionSuggestOption.source() != null ? Document.from(completionSuggestOption.source())
-                : Document.create();
-        document.setIndex(completionSuggestOption.index());
+		Document document = completionSuggestOption.source() != null ? Document.from(completionSuggestOption.source())
+				: Document.create();
+		document.setIndex(completionSuggestOption.index());
 
-        if (completionSuggestOption.id() != null) {
-            document.setId(completionSuggestOption.id());
-        }
+		if (completionSuggestOption.id() != null) {
+			document.setId(completionSuggestOption.id());
+		}
 
-        float score = completionSuggestOption.score() != null ? completionSuggestOption.score().floatValue() : Float.NaN;
-        return new SearchDocumentAdapter(document, score, new Object[]{}, Collections.emptyMap(), Collections.emptyMap(),
-                Collections.emptyMap(), null, null, null, completionSuggestOption.routing());
-    }
+		float score = completionSuggestOption.score() != null ? completionSuggestOption.score().floatValue() : Float.NaN;
+		return new SearchDocumentAdapter(document, score, new Object[] {}, Collections.emptyMap(), Collections.emptyMap(),
+				Collections.emptyMap(), null, null, null, completionSuggestOption.routing());
+	}
 
-    @Nullable
-    private static Explanation from(co.elastic.clients.elasticsearch.core.explain.@Nullable Explanation explanation) {
+	@Nullable
+	private static Explanation from(co.elastic.clients.elasticsearch.core.explain.@Nullable Explanation explanation) {
 
-        if (explanation == null) {
-            return null;
-        }
-        List<Explanation> details = explanation.details().stream().map(DocumentAdapters::from).collect(Collectors.toList());
-        return new Explanation(true, (double) explanation.value(), explanation.description(), details);
-    }
+		if (explanation == null) {
+			return null;
+		}
+		List<Explanation> details = explanation.details().stream().map(DocumentAdapters::from).collect(Collectors.toList());
+		return new Explanation(true, (double) explanation.value(), explanation.description(), details);
+	}
 
-    private static Explanation from(ExplanationDetail explanationDetail) {
+	private static Explanation from(ExplanationDetail explanationDetail) {
 
-        List<Explanation> details = explanationDetail.details().stream().map(DocumentAdapters::from)
-                .collect(Collectors.toList());
-        return new Explanation(null, (double) explanationDetail.value(), explanationDetail.description(), details);
-    }
+		List<Explanation> details = explanationDetail.details().stream().map(DocumentAdapters::from)
+				.collect(Collectors.toList());
+		return new Explanation(null, (double) explanationDetail.value(), explanationDetail.description(), details);
+	}
 
-    @Nullable
-    private static NestedMetaData from(@Nullable NestedIdentity nestedIdentity) {
+	@Nullable
+	private static NestedMetaData from(@Nullable NestedIdentity nestedIdentity) {
 
-        if (nestedIdentity == null) {
-            return null;
-        }
+		if (nestedIdentity == null) {
+			return null;
+		}
 
-        NestedMetaData child = from(nestedIdentity.nested());
-        return NestedMetaData.of(nestedIdentity.field(), nestedIdentity.offset(), child);
-    }
+		NestedMetaData child = from(nestedIdentity.nested());
+		return NestedMetaData.of(nestedIdentity.field(), nestedIdentity.offset(), child);
+	}
 
-    /**
-     * Creates a {@link Document} from a {@link GetResponse} where the found document is contained as {@link EntityAsMap}.
-     *
-     * @param getResponse the response instance
-     * @return the Document
-     */
-    @Nullable
-    public static Document from(GetResult<EntityAsMap> getResponse) {
+	/**
+	 * Creates a {@link Document} from a {@link GetResponse} where the found document is contained as {@link EntityAsMap}.
+	 *
+	 * @param getResponse the response instance
+	 * @return the Document
+	 */
+	@Nullable
+	public static Document from(GetResult<EntityAsMap> getResponse) {
 
-        Assert.notNull(getResponse, "getResponse must not be null");
+		Assert.notNull(getResponse, "getResponse must not be null");
 
-        if (!getResponse.found()) {
-            return null;
-        }
+		if (!getResponse.found()) {
+			return null;
+		}
 
-        Document document = getResponse.source() != null ? Document.from(getResponse.source()) : Document.create();
-        document.setIndex(getResponse.index());
-        document.setId(getResponse.id());
+		Document document = getResponse.source() != null ? Document.from(getResponse.source()) : Document.create();
+		document.setIndex(getResponse.index());
+		document.setId(getResponse.id());
 
-        if (getResponse.version() != null) {
-            document.setVersion(getResponse.version());
-        }
+		if (getResponse.version() != null) {
+			document.setVersion(getResponse.version());
+		}
 
-        if (getResponse.seqNo() != null) {
-            document.setSeqNo(getResponse.seqNo());
-        }
+		if (getResponse.seqNo() != null) {
+			document.setSeqNo(getResponse.seqNo());
+		}
 
-        if (getResponse.primaryTerm() != null) {
-            document.setPrimaryTerm(getResponse.primaryTerm());
-        }
+		if (getResponse.primaryTerm() != null) {
+			document.setPrimaryTerm(getResponse.primaryTerm());
+		}
 
-        return document;
-    }
+		return document;
+	}
 
-    /**
-     * Creates a list of {@link MultiGetItem}s from a {@link MgetResponse} where the data is contained as
-     * {@link EntityAsMap} instances.
-     *
-     * @param mgetResponse the response instance
-     * @return list of multiget items
-     */
-    public static List<MultiGetItem<Document>> from(MgetResponse<EntityAsMap> mgetResponse) {
+	/**
+	 * Creates a list of {@link MultiGetItem}s from a {@link MgetResponse} where the data is contained as
+	 * {@link EntityAsMap} instances.
+	 *
+	 * @param mgetResponse the response instance
+	 * @return list of multiget items
+	 */
+	public static List<MultiGetItem<Document>> from(MgetResponse<EntityAsMap> mgetResponse) {
 
-        Assert.notNull(mgetResponse, "mgetResponse must not be null");
+		Assert.notNull(mgetResponse, "mgetResponse must not be null");
 
-        return mgetResponse.docs().stream() //
-                .map(itemResponse -> MultiGetItem.of( //
-                        itemResponse.isFailure() ? null : from(itemResponse.result()), //
-                        ResponseConverter.getFailure(itemResponse)))
-                .collect(Collectors.toList());
-    }
+		return mgetResponse.docs().stream() //
+				.map(itemResponse -> MultiGetItem.of( //
+						itemResponse.isFailure() ? null : from(itemResponse.result()), //
+						ResponseConverter.getFailure(itemResponse)))
+				.collect(Collectors.toList());
+	}
 }

src/main/java/org/springframework/data/elasticsearch/client/elc/IndicesTemplate.java

@@ -114,7 +114,7 @@ public class IndicesTemplate extends ChildTemplate<ElasticsearchTransport, Elast
 	}
 
 	@Override
-	public boolean create(Map<String, Object> settings) {
+	public boolean create(Map<String, @Nullable Object> settings) {
 
 		Assert.notNull(settings, "settings must not be null");
 
@@ -122,7 +122,7 @@ public class IndicesTemplate extends ChildTemplate<ElasticsearchTransport, Elast
 	}
 
 	@Override
-	public boolean create(Map<String, Object> settings, Document mapping) {
+	public boolean create(Map<String, @Nullable Object> settings, Document mapping) {
 
 		Assert.notNull(settings, "settings must not be null");
 		Assert.notNull(mapping, "mapping must not be null");
@@ -135,7 +135,7 @@ public class IndicesTemplate extends ChildTemplate<ElasticsearchTransport, Elast
 		return doCreate(getIndexCoordinates(), createSettings(), createMapping());
 	}
 
-	protected boolean doCreate(IndexCoordinates indexCoordinates, Map<String, Object> settings,
+	protected boolean doCreate(IndexCoordinates indexCoordinates, Map<String, @Nullable Object> settings,
 			@Nullable Document mapping) {
 		Set<Alias> aliases = (boundClass != null) ? getAliasesFor(boundClass) : new HashSet<>();
 		CreateIndexSettings indexSettings = CreateIndexSettings.builder(indexCoordinates)
@@ -233,7 +233,7 @@ public class IndicesTemplate extends ChildTemplate<ElasticsearchTransport, Elast
 	}
 
 	@Override
-	public Map<String, Object> getMapping() {
+	public Map<String, @Nullable Object> getMapping() {
 
 		IndexCoordinates indexCoordinates = getIndexCoordinates();
 		GetMappingRequest getMappingRequest = requestConverter.indicesGetMappingRequest(indexCoordinates);

src/main/java/org/springframework/data/elasticsearch/client/elc/ReactiveElasticsearchTemplate.java

@@ -18,9 +18,30 @@ package org.springframework.data.elasticsearch.client.elc;
 import static co.elastic.clients.util.ApiTypeHelper.*;
 import static org.springframework.data.elasticsearch.client.elc.TypeUtils.*;
 
+import co.elastic.clients.elasticsearch._types.Result;
+import co.elastic.clients.elasticsearch.core.*;
+import co.elastic.clients.elasticsearch.core.bulk.BulkResponseItem;
+import co.elastic.clients.elasticsearch.core.search.ResponseBody;
+import co.elastic.clients.json.JsonpMapper;
+import co.elastic.clients.transport.Version;
+import co.elastic.clients.transport.endpoints.BooleanResponse;
+import io.micrometer.observation.Observation;
+import io.micrometer.observation.ObservationRegistry;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+import reactor.util.function.Tuple2;
+
+import java.time.Duration;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.function.BiFunction;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-import org.jspecify.annotations.NonNull;
 import org.jspecify.annotations.Nullable;
 import org.reactivestreams.Publisher;
 import org.springframework.beans.BeansException;
@@ -52,28 +73,6 @@ import org.springframework.util.Assert;
 import org.springframework.util.CollectionUtils;
 import org.springframework.util.StringUtils;
 
-import java.time.Duration;
-import java.util.Collection;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.function.BiFunction;
-import java.util.function.Function;
-import java.util.stream.Collectors;
-
-import co.elastic.clients.elasticsearch._types.Result;
-import co.elastic.clients.elasticsearch.core.*;
-import co.elastic.clients.elasticsearch.core.bulk.BulkResponseItem;
-import co.elastic.clients.elasticsearch.core.search.ResponseBody;
-import co.elastic.clients.json.JsonpMapper;
-import co.elastic.clients.transport.Version;
-import co.elastic.clients.transport.endpoints.BooleanResponse;
-import io.micrometer.observation.Observation;
-import io.micrometer.observation.ObservationRegistry;
-import reactor.core.publisher.Flux;
-import reactor.core.publisher.Mono;
-import reactor.util.function.Tuple2;
-
 /**
  * Implementation of {@link org.springframework.data.elasticsearch.core.ReactiveElasticsearchOperations} using the new
  * Elasticsearch client.
@@ -269,7 +268,7 @@ public class ReactiveElasticsearchTemplate extends AbstractReactiveElasticsearch
 		ExistsRequest existsRequest = requestConverter.documentExistsRequest(id, routingResolver.getRouting(), index);
 
 		return Mono.from(execute(
-				((ClientCallback<@NonNull Publisher<BooleanResponse>>) client -> client.exists(existsRequest))))
+				((ClientCallback<Publisher<BooleanResponse>>) client -> client.exists(existsRequest))))
 				.map(BooleanResponse::value) //
 				.onErrorReturn(NoSuchIndexException.class, false);
 	}
@@ -381,7 +380,7 @@ public class ReactiveElasticsearchTemplate extends AbstractReactiveElasticsearch
 
 			for (BulkResponseItem item : bulkResponse.items()) {
 
-				if (item.error() != null) {
+				if (item.error() != null && item.id() != null) {
 					failedDocuments.put(item.id(), new BulkFailureException.FailureDetails(item.status(), item.error().reason()));
 				}
 			}
@@ -538,7 +537,7 @@ public class ReactiveElasticsearchTemplate extends AbstractReactiveElasticsearch
 								return Mono.empty();
 							}
 
-							List<Object> sortOptions = hits.get(hits.size() - 1).sort().stream().map(TypeUtils::toObject)
+							List<Object> sortOptions = hits.get(hits.size() - 1).sort().stream().map(TypeUtils::toObjectNotNull)
 									.collect(Collectors.toList());
 							baseQuery.setSearchAfter(sortOptions);
 							SearchRequest followSearchRequest = requestConverter.searchRequest(baseQuery,
@@ -632,8 +631,8 @@ public class ReactiveElasticsearchTemplate extends AbstractReactiveElasticsearch
 		SearchRequest searchRequest = requestConverter.searchRequest(query, routingResolver.getRouting(), clazz, index,
 				false);
 
-		// noinspection unchecked
 		SearchDocumentCallback<T> callback = new ReadSearchDocumentCallback<>((Class<T>) clazz, index);
+
 		SearchDocumentResponse.EntityCreator<T> entityCreator = searchDocument -> callback.toEntity(searchDocument)
 				.toFuture();
 

src/main/java/org/springframework/data/elasticsearch/client/elc/ReactiveIndicesTemplate.java

@@ -108,7 +108,7 @@ public class ReactiveIndicesTemplate
 	}
 
 	@Override
-	public Mono<Boolean> create(Map<String, Object> settings) {
+	public Mono<Boolean> create(Map<String, @Nullable Object> settings) {
 
 		Assert.notNull(settings, "settings must not be null");
 
@@ -116,7 +116,7 @@ public class ReactiveIndicesTemplate
 	}
 
 	@Override
-	public Mono<Boolean> create(Map<String, Object> settings, Document mapping) {
+	public Mono<Boolean> create(Map<String, @Nullable Object> settings, Document mapping) {
 
 		Assert.notNull(settings, "settings must not be null");
 		Assert.notNull(mapping, "mapping must not be null");
@@ -132,7 +132,7 @@ public class ReactiveIndicesTemplate
 				doCreate(getIndexCoordinates(), settings, mapping))); //
 	}
 
-	private Mono<Boolean> doCreate(IndexCoordinates indexCoordinates, Map<String, Object> settings,
+	private Mono<Boolean> doCreate(IndexCoordinates indexCoordinates, Map<String, @Nullable Object> settings,
 			@Nullable Document mapping) {
 		Set<Alias> aliases = (boundClass != null) ? getAliasesFor(boundClass) : new HashSet<>();
 		CreateIndexSettings indexSettings = CreateIndexSettings.builder(indexCoordinates)
@@ -270,7 +270,7 @@ public class ReactiveIndicesTemplate
 		return getAliases(null, indexNames);
 	}
 
-	private Mono<Map<String, Set<AliasData>>> getAliases(@Nullable String[] aliasNames, @Nullable String[] indexNames) {
+	private Mono<Map<String, Set<AliasData>>> getAliases(String@Nullable [] aliasNames, String@Nullable [] indexNames) {
 
 		GetAliasRequest getAliasRequest = requestConverter.indicesGetAliasRequest(aliasNames, indexNames);
 		Mono<GetAliasResponse> getAliasResponse = Mono.from(execute(client -> client.getAlias(getAliasRequest)));

src/main/java/org/springframework/data/elasticsearch/client/elc/RequestConverter.java

@@ -74,6 +74,7 @@ import java.util.Set;
 import java.util.function.Function;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
+import java.util.Optional;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
@@ -113,6 +114,7 @@ import org.springframework.util.StringUtils;
  * @author cdalxndr
  * @author scoobyzhang
  * @author Haibo Liu
+ * @author Steven Pearce
  * @since 4.4
  */
 class RequestConverter extends AbstractQueryProcessor {
@@ -173,17 +175,9 @@ class RequestConverter extends AbstractQueryProcessor {
 	private co.elastic.clients.elasticsearch.indices.Alias.Builder buildAlias(AliasActionParameters parameters,
 			co.elastic.clients.elasticsearch.indices.Alias.Builder aliasBuilder) {
 
-		if (parameters.getRouting() != null) {
-			aliasBuilder.routing(parameters.getRouting());
-		}
-
-		if (parameters.getIndexRouting() != null) {
-			aliasBuilder.indexRouting(parameters.getIndexRouting());
-		}
-
-		if (parameters.getSearchRouting() != null) {
-			aliasBuilder.searchRouting(parameters.getSearchRouting());
-		}
+		getRouting(parameters.getRouting()).ifPresent(aliasBuilder::routing);
+		getRouting(parameters.getIndexRouting()).ifPresent(aliasBuilder::indexRouting);
+		getRouting(parameters.getSearchRouting()).ifPresent(aliasBuilder::searchRouting);
 
 		if (parameters.getHidden() != null) {
 			aliasBuilder.isHidden(parameters.getHidden());
@@ -239,12 +233,16 @@ class RequestConverter extends AbstractQueryProcessor {
 		Map<String, co.elastic.clients.elasticsearch.indices.Alias> aliases = new HashMap<>();
 		for (Alias alias : indexSettings.getAliases()) {
 			co.elastic.clients.elasticsearch.indices.Alias esAlias = co.elastic.clients.elasticsearch.indices.Alias
-					.of(ab -> ab.filter(getQuery(alias.getFilter(), null))
-							.routing(alias.getRouting())
-							.indexRouting(alias.getIndexRouting())
-							.searchRouting(alias.getSearchRouting())
-							.isHidden(alias.getHidden())
-							.isWriteIndex(alias.getWriteIndex()));
+					.of(ab -> {
+						co.elastic.clients.elasticsearch.indices.Alias.Builder aliasBuilder = ab.filter(getQuery(alias.getFilter(), null))
+								.isHidden(alias.getHidden())
+								.isWriteIndex(alias.getWriteIndex());
+						getRouting(alias.getRouting()).ifPresent(aliasBuilder::routing);
+						getRouting(alias.getIndexRouting()).ifPresent(aliasBuilder::indexRouting);
+						getRouting(alias.getSearchRouting()).ifPresent(aliasBuilder::searchRouting);
+
+						return aliasBuilder;
+					});
 			aliases.put(alias.getAlias(), esAlias);
 		}
 
@@ -318,10 +316,11 @@ class RequestConverter extends AbstractQueryProcessor {
 				addActionBuilder //
 						.indices(Arrays.asList(parameters.getIndices())) //
 						.isHidden(parameters.getHidden()) //
-						.isWriteIndex(parameters.getWriteIndex()) //
-						.routing(parameters.getRouting()) //
-						.indexRouting(parameters.getIndexRouting()) //
-						.searchRouting(parameters.getSearchRouting()); //
+						.isWriteIndex(parameters.getWriteIndex()); //
+
+				getRouting(parameters.getRouting()).ifPresent(addActionBuilder::routing);
+				getRouting(parameters.getIndexRouting()).ifPresent(addActionBuilder::indexRouting);
+				getRouting(parameters.getSearchRouting()).ifPresent(addActionBuilder::searchRouting);
 
 				if (parameters.getAliases() != null) {
 					addActionBuilder.aliases(Arrays.asList(parameters.getAliases()));
@@ -589,10 +588,11 @@ class RequestConverter extends AbstractQueryProcessor {
 			builder.version(query.getVersion()).versionType(versionType);
 		}
 
-		builder //
-				.ifSeqNo(query.getSeqNo()) //
-				.ifPrimaryTerm(query.getPrimaryTerm()) //
-				.routing(query.getRouting()); //
+		builder
+				.ifSeqNo(query.getSeqNo())
+				.ifPrimaryTerm(query.getPrimaryTerm());
+
+		getRouting(query.getRouting()).ifPresent(builder::routing);
 
 		if (query.getOpType() != null) {
 			switch (query.getOpType()) {
@@ -642,8 +642,9 @@ class RequestConverter extends AbstractQueryProcessor {
 
 		builder //
 				.ifSeqNo(query.getSeqNo()) //
-				.ifPrimaryTerm(query.getPrimaryTerm()) //
-				.routing(query.getRouting()); //
+				.ifPrimaryTerm(query.getPrimaryTerm()); //
+
+		getRouting(query.getRouting()).ifPresent(builder::routing);
 
 		return builder.build();
 	}
@@ -684,8 +685,9 @@ class RequestConverter extends AbstractQueryProcessor {
 
 		builder //
 				.ifSeqNo(query.getSeqNo()) //
-				.ifPrimaryTerm(query.getPrimaryTerm()) //
-				.routing(query.getRouting()); //
+				.ifPrimaryTerm(query.getPrimaryTerm()); //
+
+		getRouting(query.getRouting()).ifPresent(builder::routing);
 
 		return builder.build();
 	}
@@ -722,11 +724,12 @@ class RequestConverter extends AbstractQueryProcessor {
 		});
 
 		uob
-				.routing(query.getRouting())
 				.ifSeqNo(query.getIfSeqNo())
 				.ifPrimaryTerm(query.getIfPrimaryTerm())
 				.retryOnConflict(query.getRetryOnConflict());
 
+		getRouting(query.getRouting()).ifPresent(uob::routing);
+
 		// no refresh, timeout, waitForActiveShards on UpdateOperation or UpdateAction
 
 		return uob.build();
@@ -776,9 +779,7 @@ class RequestConverter extends AbstractQueryProcessor {
 			builder.pipeline(bulkOptions.getPipeline());
 		}
 
-		if (bulkOptions.getRoutingId() != null) {
-			builder.routing(bulkOptions.getRoutingId());
-		}
+		getRouting(bulkOptions.getRoutingId()).ifPresent(builder::routing);
 
 		List<BulkOperation> operations = queries.stream().map(query -> {
 			BulkOperation.Builder ob = new BulkOperation.Builder();
@@ -805,10 +806,13 @@ class RequestConverter extends AbstractQueryProcessor {
 		Assert.notNull(id, "id must not be null");
 		Assert.notNull(indexCoordinates, "indexCoordinates must not be null");
 
-		return GetRequest.of(grb -> grb //
-				.index(indexCoordinates.getIndexName()) //
-				.id(id) //
-				.routing(routing));
+		return GetRequest.of(grb -> {
+			GetRequest.Builder builder =  grb //
+					.index(indexCoordinates.getIndexName()) //
+					.id(id); //
+			getRouting(routing).ifPresent(builder::routing);
+			return builder;
+		});
 	}
 
 	public co.elastic.clients.elasticsearch.core.ExistsRequest documentExistsRequest(String id, @Nullable String routing,
@@ -817,10 +821,13 @@ class RequestConverter extends AbstractQueryProcessor {
 		Assert.notNull(id, "id must not be null");
 		Assert.notNull(indexCoordinates, "indexCoordinates must not be null");
 
-		return co.elastic.clients.elasticsearch.core.ExistsRequest.of(erb -> erb
-				.index(indexCoordinates.getIndexName())
-				.id(id)
-				.routing(routing));
+		return co.elastic.clients.elasticsearch.core.ExistsRequest.of(erb -> {
+			co.elastic.clients.elasticsearch.core.ExistsRequest.Builder builder = erb
+					.index(indexCoordinates.getIndexName())
+					.id(id);
+			getRouting(routing).ifPresent(builder::routing);
+			return builder;
+		});
 	}
 
 	public <T> MgetRequest documentMgetRequest(Query query, Class<T> clazz, IndexCoordinates index) {
@@ -838,11 +845,14 @@ class RequestConverter extends AbstractQueryProcessor {
 		SourceConfig sourceConfig = getSourceConfig(query);
 
 		List<MultiGetOperation> multiGetOperations = query.getIdsWithRouting().stream()
-				.map(idWithRouting -> MultiGetOperation.of(mgo -> mgo //
-						.index(index.getIndexName()) //
-						.id(idWithRouting.id()) //
-						.routing(idWithRouting.routing()) //
-						.source(sourceConfig)))
+				.map(idWithRouting -> MultiGetOperation.of(mgo -> {
+					MultiGetOperation.Builder builder =  mgo //
+							.index(index.getIndexName()) //
+							.id(idWithRouting.id()) //
+							.source(sourceConfig);
+					getRouting(idWithRouting.routing()).ifPresent(builder::routing);
+					return builder;
+				}))
 				.collect(Collectors.toList());
 
 		return MgetRequest.of(mg -> mg//
@@ -964,10 +974,7 @@ class RequestConverter extends AbstractQueryProcessor {
 
 		return DeleteRequest.of(r -> {
 			r.id(id).index(index.getIndexName());
-
-			if (routing != null) {
-				r.routing(routing);
-			}
+			getRouting(routing).ifPresent(r::routing);
 			r.refresh(refresh(refreshPolicy));
 			return r;
 		});
@@ -991,11 +998,7 @@ class RequestConverter extends AbstractQueryProcessor {
 
 			b.scroll(time(query.getScrollTime()));
 
-			if (query.getRoute() != null) {
-				b.routing(query.getRoute());
-			} else if (StringUtils.hasText(routing)) {
-				b.routing(routing);
-			}
+			getRouting(query.getRoute(), routing).ifPresent(b::routing);
 
 			return b;
 		});
@@ -1015,11 +1018,7 @@ class RequestConverter extends AbstractQueryProcessor {
 					.scroll(time(query.getScroll()))
 					.scrollSize(query.getScrollSize());
 
-			if (query.getRouting() != null) {
-				dqb.routing(query.getRouting());
-			} else if (StringUtils.hasText(routing)) {
-				dqb.routing(routing);
-			}
+			getRouting(query.getRouting(), routing).ifPresent(dqb::routing);
 
 			if (query.getQ() != null) {
 				dqb.q(query.getQ())
@@ -1099,7 +1098,6 @@ class RequestConverter extends AbstractQueryProcessor {
 			uqb
 					.doc(query.getDocument())
 					.upsert(query.getUpsert())
-					.routing(query.getRouting() != null ? query.getRouting() : routing)
 					.scriptedUpsert(query.getScriptedUpsert())
 					.docAsUpsert(query.getDocAsUpsert())
 					.ifSeqNo(query.getIfSeqNo())
@@ -1107,6 +1105,8 @@ class RequestConverter extends AbstractQueryProcessor {
 					.refresh(query.getRefreshPolicy() != null ? refresh(query.getRefreshPolicy()) : refresh(refreshPolicy))
 					.retryOnConflict(query.getRetryOnConflict());
 
+			getRouting(query.getRouting(), routing).ifPresent(uqb::routing);
+
 			if (query.getFetchSource() != null) {
 				uqb.source(sc -> sc.fetch(query.getFetchSource()));
 			}
@@ -1149,13 +1149,14 @@ class RequestConverter extends AbstractQueryProcessor {
 			ub //
 					.index(Arrays.asList(index.getIndexNames())) //
 					.refresh(refreshPolicy == RefreshPolicy.IMMEDIATE) //
-					.routing(updateQuery.getRouting()) //
 					.script(getScript(updateQuery.getScriptData())) //
 					.maxDocs(updateQuery.getMaxDocs() != null ? Long.valueOf(updateQuery.getMaxDocs()) : null) //
 					.pipeline(updateQuery.getPipeline()) //
 					.requestsPerSecond(updateQuery.getRequestsPerSecond()) //
 					.slices(slices(updateQuery.getSlices() != null ? Long.valueOf(updateQuery.getSlices()) : null));
 
+			getRouting(updateQuery.getRouting()).ifPresent(ub::routing);
+
 			if (updateQuery.getAbortOnVersionConflict() != null) {
 				ub.conflicts(updateQuery.getAbortOnVersionConflict() ? Conflicts.Abort : Conflicts.Proceed);
 			}
@@ -1229,12 +1230,7 @@ class RequestConverter extends AbstractQueryProcessor {
 
 		builder.query(getQuery(query, clazz));
 
-		if (StringUtils.hasText(query.getRoute())) {
-			builder.routing(query.getRoute());
-		}
-		if (StringUtils.hasText(routing)) {
-			builder.routing(routing);
-		}
+		getRouting(query.getRoute(), routing).ifPresent(builder::routing);
 
 		addPostFilter(query, builder);
 
@@ -1401,11 +1397,7 @@ class RequestConverter extends AbstractQueryProcessor {
 					.requestCache(query.getRequestCache()) //
 			;
 
-			if (StringUtils.hasText(query.getRoute())) {
-				h.routing(query.getRoute());
-			} else if (StringUtils.hasText(routing)) {
-				h.routing(routing);
-			}
+			getRouting(query.getRoute(), routing).ifPresent(h::routing);
 
 			if (query.getPreference() != null) {
 				h.preference(query.getPreference());
@@ -1451,11 +1443,7 @@ class RequestConverter extends AbstractQueryProcessor {
 				builder.expandWildcards(expandWildcards(expandWildcards));
 			}
 
-			if (query.getRoute() != null) {
-				builder.routing(query.getRoute());
-			} else if (StringUtils.hasText(routing)) {
-				builder.routing(routing);
-			}
+			getRouting(query.getRoute(), routing).ifPresent(builder::routing);
 
 			if (query.getPreference() != null) {
 				builder.preference(query.getPreference());
@@ -1886,11 +1874,7 @@ class RequestConverter extends AbstractQueryProcessor {
 			if (query.getSource() != null) {
 				builder.source(so -> so.scriptString(query.getSource()));
 			}
-			if (query.getRoute() != null) {
-				builder.routing(query.getRoute());
-			} else if (StringUtils.hasText(routing)) {
-				builder.routing(routing);
-			}
+			getRouting(query.getRoute(), routing).ifPresent(builder::routing);
 
 			var expandWildcards = query.getExpandWildcards();
 			if (expandWildcards != null && !expandWildcards.isEmpty()) {
@@ -1990,6 +1974,16 @@ class RequestConverter extends AbstractQueryProcessor {
 		return null;
 	}
 
+	Optional<String> getRouting(@Nullable String routing) {
+		if (StringUtils.hasText(routing)) {
+			return Optional.of(routing);
+		}
+		return Optional.empty();
+	}
+	Optional<String> getRouting(@Nullable String routing1, @Nullable String routing2) {
+		return getRouting(routing1).or(() -> getRouting(routing2));
+	}
+
 	private VersionType retrieveVersionTypeFromPersistentEntity(@Nullable Class<?> clazz) {
 
 		ElasticsearchPersistentEntity<?> persistentEntity = getPersistentEntity(clazz);

src/main/java/org/springframework/data/elasticsearch/client/elc/ResponseConverter.java

@@ -22,7 +22,7 @@ import co.elastic.clients.elasticsearch._types.BulkIndexByScrollFailure;
 import co.elastic.clients.elasticsearch._types.ErrorCause;
 import co.elastic.clients.elasticsearch._types.Time;
 import co.elastic.clients.elasticsearch._types.query_dsl.Query;
-import co.elastic.clients.elasticsearch.cluster.ComponentTemplateSummary;
+import co.elastic.clients.elasticsearch.cluster.ComponentTemplateSummaryRes;
 import co.elastic.clients.elasticsearch.cluster.GetComponentTemplateResponse;
 import co.elastic.clients.elasticsearch.cluster.HealthResponse;
 import co.elastic.clients.elasticsearch.core.DeleteByQueryResponse;
@@ -66,6 +66,7 @@ import org.springframework.data.elasticsearch.core.reindex.ReindexResponse;
 import org.springframework.data.elasticsearch.core.script.Script;
 import org.springframework.data.elasticsearch.core.sql.SqlResponse;
 import org.springframework.data.elasticsearch.support.DefaultStringObjectMap;
+import org.springframework.lang.Contract;
 import org.springframework.util.Assert;
 
 /**
@@ -132,7 +133,7 @@ class ResponseConverter {
 				.build();
 	}
 
-	private TemplateResponseData clusterGetComponentTemplateData(ComponentTemplateSummary componentTemplateSummary) {
+	private TemplateResponseData clusterGetComponentTemplateData(ComponentTemplateSummaryRes componentTemplateSummary) {
 
 		var mapping = typeMapping(componentTemplateSummary.mappings());
 		var settings = new Settings();
@@ -335,11 +336,11 @@ class ResponseConverter {
 				.build();
 	}
 
-	private TemplateResponseData indexGetComponentTemplateData(IndexTemplateSummary indexTemplateSummary,
+	private TemplateResponseData indexGetComponentTemplateData(IndexTemplateSummaryWithRollover indexTemplateSummary,
 			List<String> composedOf) {
 		var mapping = typeMapping(indexTemplateSummary.mappings());
 
-		Function<IndexSettings, Settings> indexSettingsToSettings = indexSettings -> {
+		Function<@Nullable IndexSettings, @Nullable Settings> indexSettingsToSettings = indexSettings -> {
 
 			if (indexSettings == null) {
 				return null;
@@ -497,7 +498,7 @@ class ResponseConverter {
 			builder.withDeleted(response.deleted());
 		}
 
-		if(response.updated() != null) {
+		if (response.updated() != null) {
 			builder.withUpdated(response.updated());
 		}
 
@@ -574,17 +575,20 @@ class ResponseConverter {
 		}
 	}
 
+	@Contract("null -> null; !null -> !null")
 	@Nullable
 	static ElasticsearchErrorCause toErrorCause(@Nullable ErrorCause errorCause) {
 
 		if (errorCause != null) {
-			return new ElasticsearchErrorCause( //
-					errorCause.type(), //
-					errorCause.reason(), //
-					errorCause.stackTrace(), //
-					toErrorCause(errorCause.causedBy()), //
-					errorCause.rootCause().stream().map(ResponseConverter::toErrorCause).collect(Collectors.toList()), //
-					errorCause.suppressed().stream().map(ResponseConverter::toErrorCause).collect(Collectors.toList()));
+			return new ElasticsearchErrorCause(
+					errorCause.type(),
+					errorCause.reason(),
+					errorCause.stackTrace(),
+					toErrorCause(errorCause.causedBy()),
+					(List<ElasticsearchErrorCause>) (errorCause.rootCause().stream()
+							.map(ResponseConverter::toErrorCause).collect(Collectors.toList())),
+					(List<ElasticsearchErrorCause>) (errorCause.suppressed().stream().map(ResponseConverter::toErrorCause)
+							.collect(Collectors.toList())));
 		} else {
 			return null;
 		}

src/main/java/org/springframework/data/elasticsearch/client/elc/TypeUtils.java

@@ -36,6 +36,7 @@ import java.util.EnumSet;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 import java.util.stream.Collectors;
 
 import org.jspecify.annotations.Nullable;
@@ -144,6 +145,12 @@ final class TypeUtils {
 		}
 	}
 
+	static Object toObjectNotNull(FieldValue fieldValue) {
+
+		Objects.requireNonNull(fieldValue);
+		return toObject(fieldValue);
+	}
+
 	@Nullable
 	static Object toObject(@Nullable FieldValue fieldValue) {
 
@@ -485,7 +492,7 @@ final class TypeUtils {
 	}
 
 	@Nullable
-	static IndexSettings indexSettings(@Nullable Map<String, Object> settings) {
+	static IndexSettings indexSettings(@Nullable Map<String, @Nullable Object> settings) {
 		return settings != null ? IndexSettings.of(b -> b.withJson(new StringReader(Document.from(settings).toJson())))
 				: null;
 	}

src/main/java/org/springframework/data/elasticsearch/client/elc/aot/ElasticsearchClientRuntimeHints.java

@@ -15,15 +15,9 @@
  */
 package org.springframework.data.elasticsearch.client.elc.aot;
 
-import co.elastic.clients.elasticsearch._types.mapping.RuntimeFieldType;
-import co.elastic.clients.elasticsearch._types.mapping.TypeMapping;
-import co.elastic.clients.elasticsearch.indices.IndexSettings;
-import co.elastic.clients.elasticsearch.indices.PutMappingRequest;
-
 import org.jspecify.annotations.Nullable;
 import org.springframework.aot.hint.RuntimeHints;
 import org.springframework.aot.hint.RuntimeHintsRegistrar;
-import org.springframework.aot.hint.TypeReference;
 import org.springframework.util.ClassUtils;
 
 /**
@@ -38,10 +32,14 @@ public class ElasticsearchClientRuntimeHints implements RuntimeHintsRegistrar {
 	public void registerHints(RuntimeHints hints, @Nullable ClassLoader classLoader) {
 
 		hints.reflection()
-				.registerType(TypeReference.of(IndexSettings.class), builder -> builder.withField("_DESERIALIZER"))
-				.registerType(TypeReference.of(PutMappingRequest.class), builder -> builder.withField("_DESERIALIZER"))
-				.registerType(TypeReference.of(RuntimeFieldType.class), builder -> builder.withField("_DESERIALIZER"))
-				.registerType(TypeReference.of(TypeMapping.class), builder -> builder.withField("_DESERIALIZER"));
+				.registerTypeIfPresent(classLoader, "co.elastic.clients.elasticsearch.indices.IndexSettings",
+						builder -> builder.withField("_DESERIALIZER"))
+				.registerTypeIfPresent(classLoader, "co.elastic.clients.elasticsearch.indices.PutMappingRequest",
+						builder -> builder.withField("_DESERIALIZER"))
+				.registerTypeIfPresent(classLoader, "co.elastic.clients.elasticsearch._types.mapping.RuntimeFieldType",
+						builder -> builder.withField("_DESERIALIZER"))
+				.registerTypeIfPresent(classLoader, "co.elastic.clients.elasticsearch._types.mapping.TypeMapping",
+						builder -> builder.withField("_DESERIALIZER"));
 
 		if (ClassUtils.isPresent("org.apache.http.impl.auth.BasicScheme",
 				ElasticsearchClientRuntimeHints.class.getClassLoader())) {

src/main/java/org/springframework/data/elasticsearch/client/elc/aot/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.client.elc.aot;

src/main/java/org/springframework/data/elasticsearch/client/elc/rest5_client/Rest5Clients.java

@@ -28,7 +28,6 @@ import org.apache.hc.core5.http.HttpHost;
 import org.apache.hc.core5.http.message.BasicHeader;
 import org.apache.hc.core5.http.nio.ssl.BasicClientTlsStrategy;
 import org.apache.hc.core5.util.Timeout;
-import org.jspecify.annotations.NonNull;
 import org.jspecify.annotations.Nullable;
 import org.springframework.data.elasticsearch.client.ClientConfiguration;
 import org.springframework.data.elasticsearch.support.HttpHeaders;
@@ -181,7 +180,7 @@ public final class Rest5Clients {
 		return builder;
 	}
 
-	private static HttpHost @NonNull [] getHttpHosts(ClientConfiguration clientConfiguration) {
+	private static HttpHost[] getHttpHosts(ClientConfiguration clientConfiguration) {
 		List<InetSocketAddress> hosts = clientConfiguration.getEndpoints();
 		boolean useSsl = clientConfiguration.useSsl();
 		return hosts.stream()

src/main/java/org/springframework/data/elasticsearch/client/elc/rest_client/RestClients.java

@@ -21,10 +21,8 @@ import org.apache.http.protocol.HttpContext;
 import org.elasticsearch.client.RequestOptions;
 import org.elasticsearch.client.RestClient;
 import org.elasticsearch.client.RestClientBuilder;
-import org.jspecify.annotations.NonNull;
 import org.jspecify.annotations.Nullable;
 import org.springframework.data.elasticsearch.client.ClientConfiguration;
-import org.springframework.data.elasticsearch.client.elc.ElasticsearchClients;
 import org.springframework.data.elasticsearch.support.HttpHeaders;
 import org.springframework.util.Assert;
 
@@ -107,7 +105,7 @@ public final class RestClients {
 		return builder;
 	}
 
-	private static HttpHost @NonNull [] getHttpHosts(ClientConfiguration clientConfiguration) {
+	private static HttpHost[] getHttpHosts(ClientConfiguration clientConfiguration) {
 		List<InetSocketAddress> hosts = clientConfiguration.getEndpoints();
 		boolean useSsl = clientConfiguration.useSsl();
 		return hosts.stream()
@@ -130,10 +128,10 @@ public final class RestClients {
 	record CustomHeaderInjector(Supplier<HttpHeaders> headersSupplier) implements HttpRequestInterceptor {
 
 		@Override
-		public void process(HttpRequest request, HttpContext context) {
+		public void process(@Nullable HttpRequest request, @Nullable HttpContext context) {
 			HttpHeaders httpHeaders = headersSupplier.get();
 
-			if (httpHeaders != null && !httpHeaders.isEmpty()) {
+			if (!httpHeaders.isEmpty() && request != null) {
 				Arrays.stream(toHeaderArray(httpHeaders)).forEach(request::addHeader);
 			}
 		}

src/main/java/org/springframework/data/elasticsearch/client/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.client;

src/main/java/org/springframework/data/elasticsearch/client/util/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.client.util;

src/main/java/org/springframework/data/elasticsearch/config/ElasticsearchConfigurationSupport.java

@@ -18,6 +18,7 @@ package org.springframework.data.elasticsearch.config;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Set;
 
 import org.jspecify.annotations.Nullable;
@@ -98,7 +99,7 @@ public class ElasticsearchConfigurationSupport {
 	protected Collection<String> getMappingBasePackages() {
 
 		Package mappingBasePackage = getClass().getPackage();
-		return Collections.singleton(mappingBasePackage == null ? null : mappingBasePackage.getName());
+		return mappingBasePackage == null ? Collections.emptyList() : List.of(mappingBasePackage.getName());
 	}
 
 	/**

src/main/java/org/springframework/data/elasticsearch/config/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.config;

src/main/java/org/springframework/data/elasticsearch/core/AbstractElasticsearchTemplate.java

@@ -59,6 +59,7 @@ import org.springframework.data.elasticsearch.support.VersionInfo;
 import org.springframework.data.mapping.callback.EntityCallbacks;
 import org.springframework.data.mapping.context.MappingContext;
 import org.springframework.data.util.Streamable;
+import org.springframework.lang.Contract;
 import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
 
@@ -260,7 +261,7 @@ public abstract class AbstractElasticsearchTemplate implements ElasticsearchOper
 		List<IndexedObjectInformation> indexedObjectInformationList = bulkIndex(indexQueries, index);
 		Iterator<IndexedObjectInformation> iterator = indexedObjectInformationList.iterator();
 
-		// noinspection unchecked
+		// noinspection unchecked,DataFlowIssue
 		return indexQueries.stream() //
 				.map(IndexQuery::getObject) //
 				.map(entity -> (T) entityOperations.updateIndexedObject(
@@ -593,7 +594,7 @@ public abstract class AbstractElasticsearchTemplate implements ElasticsearchOper
 	}
 
 	protected <T> SearchDocumentResponse.EntityCreator<T> getEntityCreator(ReadDocumentCallback<T> documentCallback) {
-		return searchDocument -> CompletableFuture.completedFuture(documentCallback.doWith(searchDocument));
+		return searchDocument -> CompletableFuture.<T> completedFuture(documentCallback.doWith(searchDocument));
 	}
 
 	/**
@@ -752,6 +753,7 @@ public abstract class AbstractElasticsearchTemplate implements ElasticsearchOper
 
 	// region Document callbacks
 	protected interface DocumentCallback<T> {
+		@Contract("null -> null")
 		@Nullable
 		T doWith(@Nullable Document document);
 	}
@@ -815,6 +817,7 @@ public abstract class AbstractElasticsearchTemplate implements ElasticsearchOper
 
 		@Override
 		public SearchHits<T> doWith(SearchDocumentResponse response) {
+			// noinspection NullableProblems,DataFlowIssue
 			List<T> entities = response.getSearchDocuments().stream().map(delegate::doWith).collect(Collectors.toList());
 			return SearchHitMapping.mappingFor(type, elasticsearchConverter).mapHits(response, entities);
 		}
@@ -835,6 +838,7 @@ public abstract class AbstractElasticsearchTemplate implements ElasticsearchOper
 
 		@Override
 		public SearchScrollHits<T> doWith(SearchDocumentResponse response) {
+			// noinspection DataFlowIssue,NullableProblems
 			List<T> entities = response.getSearchDocuments().stream().map(delegate::doWith).collect(Collectors.toList());
 			return SearchHitMapping.mappingFor(type, elasticsearchConverter).mapScrollHits(response, entities);
 		}

src/main/java/org/springframework/data/elasticsearch/core/AbstractReactiveElasticsearchTemplate.java

@@ -766,7 +766,8 @@ abstract public class AbstractReactiveElasticsearchTemplate
 	/**
 	 * Value class to capture client independent information from a response to an index request.
 	 */
-	public record IndexResponseMetaData(String id, String index, long seqNo, long primaryTerm, long version) {
+	public record IndexResponseMetaData(String id, String index, @Nullable Long seqNo, @Nullable Long primaryTerm,
+			long version) {
 	}
 	// endregion
 

src/main/java/org/springframework/data/elasticsearch/core/EntityOperations.java

@@ -17,7 +17,6 @@ package org.springframework.data.elasticsearch.core;
 
 import java.util.Map;
 
-import org.jspecify.annotations.NonNull;
 import org.jspecify.annotations.Nullable;
 import org.springframework.core.convert.ConversionService;
 import org.springframework.data.elasticsearch.core.convert.ElasticsearchConverter;
@@ -370,7 +369,7 @@ public class EntityOperations {
 		 * @see org.springframework.data.elasticsearch.core.EntityOperations.AdaptableEntity#initializeVersionProperty()
 		 */
 		@Override
-		public @NonNull T initializeVersionProperty() {
+		public T initializeVersionProperty() {
 			return map;
 		}
 
@@ -399,7 +398,7 @@ public class EntityOperations {
 		 * @see org.springframework.data.elasticsearch.core.EntityOperations.AdaptableEntity#incrementVersion()
 		 */
 		@Override
-		public @NonNull T incrementVersion() {
+		public T incrementVersion() {
 			return map;
 		}
 
@@ -408,7 +407,7 @@ public class EntityOperations {
 		 * @see org.springframework.data.elasticsearch.core.EntityOperations.Entity#getBean()
 		 */
 		@Override
-		public @NonNull T getBean() {
+		public T getBean() {
 			return map;
 		}
 

src/main/java/org/springframework/data/elasticsearch/core/IndexOperations.java

@@ -52,7 +52,7 @@ public interface IndexOperations {
 	 * @param settings the index settings
 	 * @return {@literal true} if the index was created
 	 */
-	boolean create(Map<String, Object> settings);
+	boolean create(Map<String, @Nullable Object> settings);
 
 	/**
 	 * Create an index for given settings and mapping.
@@ -62,7 +62,7 @@ public interface IndexOperations {
 	 * @return {@literal true} if the index was created
 	 * @since 4.2
 	 */
-	boolean create(Map<String, Object> settings, Document mapping);
+	boolean create(Map<String, @Nullable Object> settings, Document mapping);
 
 	/**
 	 * Create an index with the settings and mapping defined for the entity this IndexOperations is bound to.
@@ -142,7 +142,7 @@ public interface IndexOperations {
 	 *
 	 * @return the mapping
 	 */
-	Map<String, Object> getMapping();
+	Map<String, @Nullable Object> getMapping();
 
 	// endregion
 

src/main/java/org/springframework/data/elasticsearch/core/IndexOperationsAdapter.java

@@ -46,12 +46,12 @@ public interface IndexOperationsAdapter extends IndexOperations {
 			}
 
 			@Override
-			public boolean create(Map<String, Object> settings) {
+			public boolean create(Map<String, @Nullable Object> settings) {
 				return Boolean.TRUE.equals(reactiveIndexOperations.create(settings).block());
 			}
 
 			@Override
-			public boolean create(Map<String, Object> settings, Document mapping) {
+			public boolean create(Map<String, @Nullable Object> settings, Document mapping) {
 				return Boolean.TRUE.equals(reactiveIndexOperations.create(settings, mapping).block());
 			}
 
@@ -92,7 +92,7 @@ public interface IndexOperationsAdapter extends IndexOperations {
 			}
 
 			@Override
-			public Map<String, Object> getMapping() {
+			public Map<String, @Nullable Object> getMapping() {
 				return Objects.requireNonNull(reactiveIndexOperations.getMapping().block());
 			}
 

src/main/java/org/springframework/data/elasticsearch/core/MultiGetItem.java

@@ -36,7 +36,7 @@ public class MultiGetItem<T> {
 	}
 
 	public static <T> MultiGetItem<T> of(@Nullable T item, @Nullable Failure failure) {
-		return new MultiGetItem<>(item, failure);
+		return new MultiGetItem(item, failure);
 	}
 
 	public boolean hasItem() {

src/main/java/org/springframework/data/elasticsearch/core/ReactiveIndexOperations.java

@@ -21,6 +21,7 @@ import reactor.core.publisher.Mono;
 import java.util.Map;
 import java.util.Set;
 
+import org.jspecify.annotations.Nullable;
 import org.springframework.data.elasticsearch.core.document.Document;
 import org.springframework.data.elasticsearch.core.index.*;
 import org.springframework.data.elasticsearch.core.mapping.IndexCoordinates;
@@ -50,7 +51,7 @@ public interface ReactiveIndexOperations {
 	 * @return a {@link Mono} signalling successful operation completion or an {@link Mono#error(Throwable) error} if eg.
 	 *         the index already exist.
 	 */
-	Mono<Boolean> create(Map<String, Object> settings);
+	Mono<Boolean> create(Map<String, @Nullable Object> settings);
 
 	/**
 	 * Create an index for given settings and mapping.
@@ -61,7 +62,7 @@ public interface ReactiveIndexOperations {
 	 *         the index already exist.
 	 * @since 4.2
 	 */
-	Mono<Boolean> create(Map<String, Object> settings, Document mapping);
+	Mono<Boolean> create(Map<String, @Nullable Object> settings, Document mapping);
 
 	/**
 	 * Create an index with the settings and mapping defined for the entity this IndexOperations is bound to.

src/main/java/org/springframework/data/elasticsearch/core/SearchHit.java

@@ -51,7 +51,7 @@ public class SearchHit<T> {
 	private final Map<String, Double> matchedQueries = new LinkedHashMap<>();
 
 	public SearchHit(@Nullable String index, @Nullable String id, @Nullable String routing, float score,
-			@Nullable Object[] sortValues, @Nullable Map<String, List<String>> highlightFields,
+			Object @Nullable [] sortValues, @Nullable Map<String, List<String>> highlightFields,
 			@Nullable Map<String, SearchHits<?>> innerHits, @Nullable NestedMetaData nestedMetaData,
 			@Nullable Explanation explanation, @Nullable Map<String, Double> matchedQueries, T content) {
 		this.index = index;
@@ -193,7 +193,6 @@ public class SearchHit<T> {
 	/**
 	 * @return the matched queries for this SearchHit.
 	 */
-	@Nullable
 	public Map<String, Double> getMatchedQueries() {
 		return matchedQueries;
 	}

src/main/java/org/springframework/data/elasticsearch/core/SearchHitSupport.java

@@ -22,11 +22,11 @@ import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
 import org.jspecify.annotations.Nullable;
-
 import org.springframework.data.core.ReactiveWrappers;
 import org.springframework.data.domain.PageImpl;
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.util.CloseableIterator;
+import org.springframework.lang.Contract;
 
 /**
  * Utility class with helper methods for working with {@link SearchHit}.
@@ -47,6 +47,7 @@ public final class SearchHitSupport {
 	 * @return a corresponding object where the SearchHits are replaced by their content if possible, otherwise the
 	 *         original object
 	 */
+	@Contract("null -> null; !null -> !null")
 	@Nullable
 	public static Object unwrapSearchHits(@Nullable Object result) {
 

src/main/java/org/springframework/data/elasticsearch/core/SearchHitsImpl.java

@@ -133,7 +133,7 @@ public class SearchHitsImpl<T> implements SearchScrollHits<T> {
 	}
 
 	@Override
-	public SearchShardStatistics getSearchShardStatistics() {
+	public @Nullable SearchShardStatistics getSearchShardStatistics() {
 		return searchShardStatistics;
 	}
 

src/main/java/org/springframework/data/elasticsearch/core/cluster/package-info.java

@@ -1,5 +1,18 @@
-/**
- * Interfaces and classes related to Elasticsearch cluster information and management.
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
  */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.core.cluster;

src/main/java/org/springframework/data/elasticsearch/core/convert/ElasticsearchTypeMapper.java

@@ -29,7 +29,7 @@ import org.springframework.data.mapping.context.MappingContext;
  * @author Christoph Strobl
  * @since 3.2
  */
-public interface ElasticsearchTypeMapper extends TypeMapper<Map<String, Object>> {
+public interface ElasticsearchTypeMapper extends TypeMapper<Map<String, @Nullable Object>> {
 
 	String DEFAULT_TYPE_KEY = "_class";
 
@@ -47,7 +47,7 @@ public interface ElasticsearchTypeMapper extends TypeMapper<Map<String, Object>>
 	@Nullable
 	String getTypeKey();
 
-	default boolean containsTypeInformation(Map<String, Object> source) {
+	default boolean containsTypeInformation(Map<String, @Nullable Object> source) {
 		return readType(source) != null;
 	}
 

src/main/java/org/springframework/data/elasticsearch/core/convert/GeoConverters.java

@@ -20,9 +20,9 @@ import java.util.Collection;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
-import java.util.Objects;
 import java.util.stream.Collectors;
 
+import org.jspecify.annotations.Nullable;
 import org.springframework.core.convert.converter.Converter;
 import org.springframework.data.convert.ReadingConverter;
 import org.springframework.data.convert.WritingConverter;
@@ -167,7 +167,7 @@ public class GeoConverters {
 		INSTANCE;
 
 		@Override
-		public GeoJson<? extends Iterable<?>> convert(Map<String, Object> source) {
+		public GeoJson<? extends Iterable<?>> convert(Map<String, @Nullable Object> source) {
 
 			String type = GeoConverters.getGeoJsonType(source);
 
@@ -206,7 +206,7 @@ public class GeoConverters {
 		INSTANCE;
 
 		@Override
-		public GeoJsonPoint convert(Map<String, Object> source) {
+		public GeoJsonPoint convert(Map<String, @Nullable Object> source) {
 
 			String type = GeoConverters.getGeoJsonType(source);
 			Assert.isTrue(type.equalsIgnoreCase(GeoJsonPoint.TYPE), "does not contain a type 'Point'");
@@ -244,7 +244,7 @@ public class GeoConverters {
 		INSTANCE;
 
 		@Override
-		public GeoJsonMultiPoint convert(Map<String, Object> source) {
+		public GeoJsonMultiPoint convert(Map<String, @Nullable Object> source) {
 
 			String type = GeoConverters.getGeoJsonType(source);
 			Assert.isTrue(type.equalsIgnoreCase(GeoJsonMultiPoint.TYPE), "does not contain a type 'MultiPoint'");
@@ -279,7 +279,7 @@ public class GeoConverters {
 		INSTANCE;
 
 		@Override
-		public GeoJsonLineString convert(Map<String, Object> source) {
+		public GeoJsonLineString convert(Map<String, @Nullable Object> source) {
 
 			String type = GeoConverters.getGeoJsonType(source);
 			Assert.isTrue(type.equalsIgnoreCase(GeoJsonLineString.TYPE), "does not contain a type 'LineString'");
@@ -311,7 +311,7 @@ public class GeoConverters {
 		INSTANCE;
 
 		@Override
-		public GeoJsonMultiLineString convert(Map<String, Object> source) {
+		public GeoJsonMultiLineString convert(Map<String, @Nullable Object> source) {
 
 			String type = GeoConverters.getGeoJsonType(source);
 			Assert.isTrue(type.equalsIgnoreCase(GeoJsonMultiLineString.TYPE), "does not contain a type 'MultiLineString'");
@@ -339,7 +339,7 @@ public class GeoConverters {
 		INSTANCE;
 
 		@Override
-		public GeoJsonPolygon convert(Map<String, Object> source) {
+		public GeoJsonPolygon convert(Map<String, @Nullable Object> source) {
 
 			String type = GeoConverters.getGeoJsonType(source);
 			Assert.isTrue(type.equalsIgnoreCase(GeoJsonPolygon.TYPE), "does not contain a type 'Polygon'");
@@ -368,7 +368,6 @@ public class GeoConverters {
 
 			List<Object> coordinates = source.getCoordinates().stream() //
 					.map(GeoJsonPolygonToMapConverter.INSTANCE::convert) //
-					.filter(Objects::nonNull) //
 					.map(it -> it.get("coordinates")) //
 					.collect(Collectors.toList()); //
 			map.put("coordinates", coordinates);
@@ -383,7 +382,7 @@ public class GeoConverters {
 		INSTANCE;
 
 		@Override
-		public GeoJsonMultiPolygon convert(Map<String, Object> source) {
+		public GeoJsonMultiPolygon convert(Map<String, @Nullable Object> source) {
 
 			String type = GeoConverters.getGeoJsonType(source);
 			Assert.isTrue(type.equalsIgnoreCase(GeoJsonMultiPolygon.TYPE), "does not contain a type 'MultiPolygon'");
@@ -430,7 +429,7 @@ public class GeoConverters {
 		INSTANCE;
 
 		@Override
-		public GeoJsonGeometryCollection convert(Map<String, Object> source) {
+		public GeoJsonGeometryCollection convert(Map<String, @Nullable Object> source) {
 
 			String type = GeoConverters.getGeoJsonType(source);
 			Assert.isTrue(type.equalsIgnoreCase(GeoJsonGeometryCollection.TYPE),
@@ -448,7 +447,7 @@ public class GeoConverters {
 	// endregion
 
 	// region helper functions
-	private static String getGeoJsonType(Map<String, Object> source) {
+	private static String getGeoJsonType(Map<String, @Nullable Object> source) {
 
 		Object type = source.get("type");
 		Assert.notNull(type, "Document to convert does not contain a type");
@@ -485,7 +484,7 @@ public class GeoConverters {
 		return map;
 	}
 
-	private static List<GeoJsonLineString> geoJsonLineStringsFromMap(Map<String, Object> source) {
+	private static List<GeoJsonLineString> geoJsonLineStringsFromMap(Map<String, @Nullable Object> source) {
 		Object coordinates = source.get("coordinates");
 		Assert.notNull(coordinates, "Document to convert does not contain coordinates");
 		Assert.isTrue(coordinates instanceof List, "coordinates must be a List");

src/main/java/org/springframework/data/elasticsearch/core/convert/MappingElasticsearchConverter.java

@@ -24,7 +24,6 @@ import java.util.stream.Collectors;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.jspecify.annotations.Nullable;
-
 import org.springframework.beans.BeansException;
 import org.springframework.beans.factory.InitializingBean;
 import org.springframework.context.ApplicationContext;
@@ -63,16 +62,7 @@ import org.springframework.data.mapping.Parameter;
 import org.springframework.data.mapping.PersistentPropertyAccessor;
 import org.springframework.data.mapping.SimplePropertyHandler;
 import org.springframework.data.mapping.context.MappingContext;
-import org.springframework.data.mapping.model.CachingValueExpressionEvaluatorFactory;
-import org.springframework.data.mapping.model.ConvertingPropertyAccessor;
-import org.springframework.data.mapping.model.EntityInstantiator;
-import org.springframework.data.mapping.model.EntityInstantiators;
-import org.springframework.data.mapping.model.ParameterValueProvider;
-import org.springframework.data.mapping.model.PersistentEntityParameterValueProvider;
-import org.springframework.data.mapping.model.PropertyValueProvider;
-import org.springframework.data.mapping.model.SpELContext;
-import org.springframework.data.mapping.model.ValueExpressionEvaluator;
-import org.springframework.data.mapping.model.ValueExpressionParameterValueProvider;
+import org.springframework.data.mapping.model.*;
 import org.springframework.expression.spel.standard.SpelExpressionParser;
 import org.springframework.format.datetime.DateFormatterRegistrar;
 import org.springframework.util.Assert;
@@ -267,7 +257,7 @@ public class MappingElasticsearchConverter
 
 		@Nullable
 		@SuppressWarnings("unchecked")
-		private <R> R read(TypeInformation<R> typeInformation, Map<String, Object> source) {
+		private <R> R read(TypeInformation<R> typeInformation, Map<String, @Nullable Object> source) {
 
 			Assert.notNull(source, "Source must not be null!");
 
@@ -301,7 +291,7 @@ public class MappingElasticsearchConverter
 		}
 
 		@SuppressWarnings("unchecked")
-		private <R> R readMap(TypeInformation<?> type, Map<String, Object> source) {
+		private <R> R readMap(TypeInformation<?> type, Map<String, @Nullable Object> source) {
 
 			Assert.notNull(source, "Document must not be null!");
 
@@ -313,9 +303,10 @@ public class MappingElasticsearchConverter
 			Class<?> rawKeyType = keyType != null ? keyType.getType() : null;
 			Class<?> rawValueType = valueType != null ? valueType.getType() : null;
 
-			Map<Object, Object> map = CollectionFactory.createMap(mapType, rawKeyType, source.keySet().size());
+			Map<Object, @Nullable Object> map = (Map<Object, @Nullable Object>) CollectionFactory.createMap(mapType,
+					rawKeyType, source.keySet().size());
 
-			for (Entry<String, Object> entry : source.entrySet()) {
+			for (Entry<String, @Nullable Object> entry : source.entrySet()) {
 
 				if (typeMapper.isTypeKey(entry.getKey())) {
 					continue;
@@ -325,6 +316,7 @@ public class MappingElasticsearchConverter
 
 				if (rawKeyType != null && !rawKeyType.isAssignableFrom(key.getClass())) {
 					key = conversionService.convert(key, rawKeyType);
+					Assert.notNull(key, "converted key must not be null");
 				}
 
 				Object value = entry.getValue();
@@ -343,7 +335,7 @@ public class MappingElasticsearchConverter
 			return (R) map;
 		}
 
-		private <R> R readEntity(ElasticsearchPersistentEntity<?> entity, Map<String, Object> source) {
+		private <R> R readEntity(ElasticsearchPersistentEntity<?> entity, Map<String, @Nullable Object> source) {
 
 			ElasticsearchPersistentEntity<?> targetEntity = computeClosestEntity(entity, source);
 			ValueExpressionEvaluator evaluator = expressionEvaluatorFactory.create(source);
@@ -582,7 +574,7 @@ public class MappingElasticsearchConverter
 					: TypeInformation.OBJECT;
 			Class<?> rawComponentType = componentType.getType();
 
-			Collection<Object> items = targetType.getType().isArray() //
+			Collection<@Nullable Object> items = targetType.getType().isArray() //
 					? new ArrayList<>(source.size()) //
 					: CollectionFactory.createCollection(collectionType, rawComponentType, source.size());
 
@@ -672,7 +664,7 @@ public class MappingElasticsearchConverter
 		 */
 		private <T> void populateScriptedFields(ElasticsearchPersistentEntity<?> entity, T result,
 				SearchDocument searchDocument) {
-			Map<String, List<Object>> fields = searchDocument.getFields();
+			Map<String, List<@Nullable Object>> fields = searchDocument.getFields();
 			entity.doWithProperties((SimplePropertyHandler) property -> {
 				if (property.isAnnotationPresent(ScriptedField.class)) {
 					ScriptedField scriptedField = property.findAnnotation(ScriptedField.class);
@@ -695,7 +687,7 @@ public class MappingElasticsearchConverter
 		 * Compute the type to use by checking the given entity against the store type;
 		 */
 		private ElasticsearchPersistentEntity<?> computeClosestEntity(ElasticsearchPersistentEntity<?> entity,
-				Map<String, Object> source) {
+				Map<String, @Nullable Object> source) {
 
 			TypeInformation<?> typeToUse = typeMapper.readType(source);
 
@@ -770,7 +762,7 @@ public class MappingElasticsearchConverter
 			INSTANCE;
 
 			@Override
-			public <T> T getParameterValue(Parameter<T, ElasticsearchPersistentProperty> parameter) {
+			public <T> @Nullable T getParameterValue(Parameter<T, ElasticsearchPersistentProperty> parameter) {
 				return null;
 			}
 		}
@@ -822,7 +814,7 @@ public class MappingElasticsearchConverter
 		 * @param typeInformation type information for the source
 		 */
 		@SuppressWarnings("unchecked")
-		private void writeInternal(@Nullable Object source, Map<String, Object> sink,
+		private void writeInternal(@Nullable Object source, Map<String, @Nullable Object> sink,
 				@Nullable TypeInformation<?> typeInformation) {
 
 			if (null == source) {
@@ -833,7 +825,7 @@ public class MappingElasticsearchConverter
 			Optional<Class<?>> customTarget = conversions.getCustomWriteTarget(entityType, Map.class);
 
 			if (customTarget.isPresent()) {
-				Map<String, Object> result = conversionService.convert(source, Map.class);
+				Map<String, @Nullable Object> result = conversionService.convert(source, Map.class);
 
 				if (result != null) {
 					sink.putAll(result);
@@ -863,7 +855,7 @@ public class MappingElasticsearchConverter
 		 * @param sink the destination
 		 * @param entity entity for the source
 		 */
-		private void writeInternal(@Nullable Object source, Map<String, Object> sink,
+		private void writeInternal(@Nullable Object source, Map<String, @Nullable Object> sink,
 				@Nullable ElasticsearchPersistentEntity<?> entity) {
 
 			if (source == null) {
@@ -905,7 +897,7 @@ public class MappingElasticsearchConverter
 		 * @param sink must not be {@literal null}.
 		 * @param propertyType must not be {@literal null}.
 		 */
-		private Map<String, Object> writeMapInternal(Map<?, ?> source, Map<String, Object> sink,
+		private Map<String, @Nullable Object> writeMapInternal(Map<?, ?> source, Map<String, @Nullable Object> sink,
 				TypeInformation<?> propertyType) {
 
 			for (Map.Entry<?, ?> entry : source.entrySet()) {
@@ -922,7 +914,7 @@ public class MappingElasticsearchConverter
 						sink.put(simpleKey,
 								writeCollectionInternal(asCollection(value), propertyType.getMapValueType(), new ArrayList<>()));
 					} else {
-						Map<String, Object> document = Document.create();
+						Map<String, @Nullable Object> document = Document.create();
 						TypeInformation<?> valueTypeInfo = propertyType.isMap() ? propertyType.getMapValueType()
 								: TypeInformation.OBJECT;
 						writeInternal(value, document, valueTypeInfo);
@@ -966,7 +958,7 @@ public class MappingElasticsearchConverter
 				} else if (element instanceof Collection || elementType.isArray()) {
 					collection.add(writeCollectionInternal(asCollection(element), componentType, new ArrayList<>()));
 				} else {
-					Map<String, Object> document = Document.create();
+					Map<String, @Nullable Object> document = Document.create();
 					writeInternal(element, document, componentType);
 					collection.add(document);
 				}
@@ -1080,7 +1072,7 @@ public class MappingElasticsearchConverter
 					: mappingContext.getRequiredPersistentEntity(type);
 
 			Object existingValue = sink.get(property);
-			Map<String, Object> document = existingValue instanceof Map ? (Map<String, Object>) existingValue
+			Map<String, @Nullable Object> document = existingValue instanceof Map ? (Map<String, Object>) existingValue
 					: Document.create();
 
 			addCustomTypeKeyIfNecessary(value, document, TypeInformation.of(property.getRawType()));
@@ -1097,7 +1089,7 @@ public class MappingElasticsearchConverter
 		 * @param sink must not be {@literal null}.
 		 * @param type type to compare to
 		 */
-		private void addCustomTypeKeyIfNecessary(Object source, Map<String, Object> sink,
+		private void addCustomTypeKeyIfNecessary(Object source, Map<String, @Nullable Object> sink,
 				@Nullable TypeInformation<?> type) {
 
 			if (!writeTypeHints) {
@@ -1218,7 +1210,7 @@ public class MappingElasticsearchConverter
 			Assert.notNull(map, "Given map must not be null!");
 			Assert.notNull(property, "PersistentProperty must not be null!");
 
-			return writeMapInternal(map, new LinkedHashMap<>(map.size()), property.getTypeInformation());
+			return writeMapInternal(map, new LinkedHashMap(map.size()), property.getTypeInformation());
 		}
 
 		/**
@@ -1492,9 +1484,9 @@ public class MappingElasticsearchConverter
 	@SuppressWarnings("ClassCanBeRecord")
 	static class MapValueAccessor {
 
-		final Map<String, Object> target;
+		final Map<String, @Nullable Object> target;
 
-		MapValueAccessor(Map<String, Object> target) {
+		MapValueAccessor(Map<String, @Nullable Object> target) {
 			this.target = target;
 		}
 
@@ -1528,7 +1520,7 @@ public class MappingElasticsearchConverter
 			}
 
 			Iterator<String> parts = Arrays.asList(fieldName.split("\\.")).iterator();
-			Map<String, Object> source = target;
+			Map<String, @Nullable Object> source = target;
 			Object result = null;
 
 			while (parts.hasNext()) {
@@ -1559,11 +1551,11 @@ public class MappingElasticsearchConverter
 			target.put(property.getFieldName(), value);
 		}
 
-		private Map<String, Object> getAsMap(Object result) {
+		private Map<String, @Nullable Object> getAsMap(Object result) {
 
 			if (result instanceof Map) {
 				// noinspection unchecked
-				return (Map<String, Object>) result;
+				return (Map<String, @Nullable Object>) result;
 			}
 
 			throw new IllegalArgumentException(String.format("%s is not a Map.", result));

src/main/java/org/springframework/data/elasticsearch/core/convert/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.core.convert;

src/main/java/org/springframework/data/elasticsearch/core/document/Explanation.java

@@ -62,7 +62,7 @@ public class Explanation {
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		if (this == o)
 			return true;
 		if (o == null || getClass() != o.getClass())
@@ -81,7 +81,7 @@ public class Explanation {
 
 	@Override
 	public int hashCode() {
-		int result = (match ? 1 : 0);
+		int result = (Boolean.TRUE.equals(match) ? 1 : 0);
 		result = 31 * result + value.hashCode();
 		result = 31 * result + (description != null ? description.hashCode() : 0);
 		result = 31 * result + details.hashCode();

src/main/java/org/springframework/data/elasticsearch/core/document/MapDocument.java

@@ -215,7 +215,7 @@ class MapDocument implements Document {
 	 * @see java.util.Map#containsKey(java.lang.Object)
 	 */
 	@Override
-	public boolean containsKey(Object key) {
+	public boolean containsKey(@Nullable Object key) {
 		return documentAsMap.containsKey(key);
 	}
 
@@ -224,7 +224,7 @@ class MapDocument implements Document {
 	 * @see java.util.Map#containsValue(java.lang.Object)
 	 */
 	@Override
-	public boolean containsValue(Object value) {
+	public boolean containsValue(@Nullable Object value) {
 		return documentAsMap.containsValue(value);
 	}
 
@@ -233,7 +233,7 @@ class MapDocument implements Document {
 	 * @see java.util.Map#get(java.lang.Object)
 	 */
 	@Override
-	public Object get(Object key) {
+	public Object get(@Nullable Object key) {
 		return documentAsMap.get(key);
 	}
 
@@ -242,7 +242,7 @@ class MapDocument implements Document {
 	 * @see java.lang.Object#getOrDefault(java.lang.Object, java.lang.Object)
 	 */
 	@Override
-	public Object getOrDefault(Object key, Object defaultValue) {
+	public Object getOrDefault(@Nullable Object key, @Nullable Object defaultValue) {
 		return documentAsMap.getOrDefault(key, defaultValue);
 	}
 
@@ -251,7 +251,7 @@ class MapDocument implements Document {
 	 * @see java.util.Map#put(java.lang.Object, java.lang.Object)
 	 */
 	@Override
-	public Object put(String key, Object value) {
+	public Object put(String key, @Nullable Object value) {
 		return documentAsMap.put(key, value);
 	}
 
@@ -260,7 +260,7 @@ class MapDocument implements Document {
 	 * @see java.util.Map#remove(java.lang.Object)
 	 */
 	@Override
-	public Object remove(Object key) {
+	public Object remove(@Nullable Object key) {
 		return documentAsMap.remove(key);
 	}
 
@@ -314,7 +314,7 @@ class MapDocument implements Document {
 	 * @see java.lang.Object#equals(java.lang.Object)
 	 */
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		return documentAsMap.equals(o);
 	}
 
@@ -332,7 +332,8 @@ class MapDocument implements Document {
 	 * @see java.util.Map#forEach(java.util.function.BiConsumer)
 	 */
 	@Override
-	public void forEach(BiConsumer<? super String, ? super Object> action) {
+	public void forEach(
+			@SuppressWarnings("NullableProblems") BiConsumer<? super String, ? super @Nullable Object> action) {
 		documentAsMap.forEach(action);
 	}
 

src/main/java/org/springframework/data/elasticsearch/core/document/SearchDocument.java

@@ -41,7 +41,7 @@ public interface SearchDocument extends Document {
 	/**
 	 * @return the fields for the search result, not {@literal null}
 	 */
-	Map<String, List<Object>> getFields();
+	Map<String, List<@Nullable Object>> getFields();
 
 	/**
 	 * The first value of the given field.
@@ -50,7 +50,7 @@ public interface SearchDocument extends Document {
 	 */
 	@Nullable
 	default <V> V getFieldValue(final String name) {
-		List<Object> values = getFields().get(name);
+		List<@Nullable Object> values = getFields().get(name);
 		if (values == null || values.isEmpty()) {
 			return null;
 		}
@@ -64,7 +64,7 @@ public interface SearchDocument extends Document {
 	 */
 	@Nullable
 	default <V> List<V> getFieldValues(final String name) {
-		List<Object> values = getFields().get(name);
+		List<@Nullable Object> values = getFields().get(name);
 		if (values == null) {
 			return null;
 		}
@@ -74,8 +74,7 @@ public interface SearchDocument extends Document {
 	/**
 	 * @return the sort values for the search hit
 	 */
-	@Nullable
-	default Object[] getSortValues() {
+	default Object @Nullable [] getSortValues() {
 		return null;
 	}
 

src/main/java/org/springframework/data/elasticsearch/core/document/SearchDocumentAdapter.java

@@ -35,7 +35,7 @@ public class SearchDocumentAdapter implements SearchDocument {
 
 	private final float score;
 	private final Object[] sortValues;
-	private final Map<String, List<Object>> fields = new HashMap<>();
+	private final Map<String, List<@Nullable Object>> fields = new HashMap<>();
 	private final Document delegate;
 	private final Map<String, List<String>> highlightFields = new HashMap<>();
 	private final Map<String, SearchDocumentResponse> innerHits = new HashMap<>();
@@ -44,9 +44,11 @@ public class SearchDocumentAdapter implements SearchDocument {
 	@Nullable private final Map<String, Double> matchedQueries;
 	@Nullable private final String routing;
 
-	public SearchDocumentAdapter(Document delegate, float score, Object[] sortValues, Map<String, List<Object>> fields,
+	public SearchDocumentAdapter(Document delegate, float score, Object[] sortValues,
+			Map<String, List<@Nullable Object>> fields,
 			Map<String, List<String>> highlightFields, Map<String, SearchDocumentResponse> innerHits,
-			@Nullable NestedMetaData nestedMetaData, @Nullable Explanation explanation, @Nullable Map<String, Double> matchedQueries,
+			@Nullable NestedMetaData nestedMetaData, @Nullable Explanation explanation,
+			@Nullable Map<String, Double> matchedQueries,
 			@Nullable String routing) {
 
 		this.delegate = delegate;
@@ -74,7 +76,7 @@ public class SearchDocumentAdapter implements SearchDocument {
 	}
 
 	@Override
-	public Map<String, List<Object>> getFields() {
+	public Map<String, List<@Nullable Object>> getFields() {
 		return fields;
 	}
 
@@ -186,17 +188,17 @@ public class SearchDocumentAdapter implements SearchDocument {
 	}
 
 	@Override
-	public boolean containsKey(Object key) {
+	public boolean containsKey(@Nullable Object key) {
 		return delegate.containsKey(key);
 	}
 
 	@Override
-	public boolean containsValue(Object value) {
+	public boolean containsValue(@Nullable Object value) {
 		return delegate.containsValue(value);
 	}
 
 	@Override
-	public Object get(Object key) {
+	public Object get(@Nullable Object key) {
 
 		if (delegate.containsKey(key)) {
 			return delegate.get(key);
@@ -207,12 +209,12 @@ public class SearchDocumentAdapter implements SearchDocument {
 	}
 
 	@Override
-	public Object put(String key, Object value) {
+	public @Nullable Object put(String key, @Nullable Object value) {
 		return delegate.put(key, value);
 	}
 
 	@Override
-	public Object remove(Object key) {
+	public Object remove(@Nullable Object key) {
 		return delegate.remove(key);
 	}
 
@@ -232,12 +234,12 @@ public class SearchDocumentAdapter implements SearchDocument {
 	}
 
 	@Override
-	public Collection<Object> values() {
+	public Collection<@Nullable Object> values() {
 		return delegate.values();
 	}
 
 	@Override
-	public Set<Entry<String, Object>> entrySet() {
+	public Set<Entry<String, @Nullable Object>> entrySet() {
 		return delegate.entrySet();
 	}
 
@@ -254,7 +256,7 @@ public class SearchDocumentAdapter implements SearchDocument {
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		if (this == o) {
 			return true;
 		}
@@ -270,17 +272,17 @@ public class SearchDocumentAdapter implements SearchDocument {
 	}
 
 	@Override
-	public void forEach(BiConsumer<? super String, ? super Object> action) {
+	public void forEach(@Nullable BiConsumer<? super String, ? super @Nullable Object> action) {
 		delegate.forEach(action);
 	}
 
 	@Override
-	public boolean remove(Object key, Object value) {
+	public boolean remove(@Nullable Object key, @Nullable Object value) {
 		return delegate.remove(key, value);
 	}
 
 	@Override
-	public String getRouting() {
+	public @Nullable String getRouting() {
 		return routing;
 	}
 

src/main/java/org/springframework/data/elasticsearch/core/document/package-info.java

@@ -1,5 +1,18 @@
-/**
- * Classes related to the Document structure of Elasticsearch documents and search responses.
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
  */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.core.document;

src/main/java/org/springframework/data/elasticsearch/core/event/AfterLoadCallback.java

@@ -31,10 +31,11 @@ import org.springframework.data.mapping.callback.EntityCallback;
 public interface AfterLoadCallback<T> extends EntityCallback<Document> {
 
 	/**
-	 * Entity callback method invoked after a domain object is materialized from a {@link Document}. Can return either the
-	 * same or a modified instance of the {@link Document} object.
+	 * Entity callback method invoked after a {@link Document} is read from Elasticsearch. Can return either the same or a
+	 * modified instance of the {@link Document} object.
 	 *
 	 * @param document the document.
+	 * @param type the type into which the document will be converted
 	 * @param indexCoordinates of the index the document was read from.
 	 * @return a possible modified or new {@link Document}.
 	 */

src/main/java/org/springframework/data/elasticsearch/core/event/package-info.java

@@ -1,5 +1,18 @@
-/**
- * classes and interfaces related to Spring Data Elasticsearch events and callbacks.
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
  */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.core.event;

src/main/java/org/springframework/data/elasticsearch/core/geo/CustomGeoModule.java

@@ -8,18 +8,27 @@ import tools.jackson.databind.SerializationContext;
 import tools.jackson.databind.ValueDeserializer;
 import tools.jackson.databind.ValueSerializer;
 
+import org.jspecify.annotations.Nullable;
 import org.springframework.data.geo.Point;
+import org.springframework.util.Assert;
 
 class PointSerializer extends ValueSerializer<Point> {
 	@Override
-	public void serialize(Point value, JsonGenerator gen, SerializationContext serializers) throws JacksonException {
+	public void serialize(Point value, @Nullable JsonGenerator gen, @Nullable SerializationContext serializers)
+			throws JacksonException {
+
+		Assert.notNull(gen, "gen must not be null");
+
 		gen.writePOJO(GeoPoint.fromPoint(value));
 	}
 }
 
 class PointDeserializer extends ValueDeserializer<Point> {
 	@Override
-	public Point deserialize(JsonParser p, DeserializationContext context) throws JacksonException {
+	public Point deserialize(@Nullable JsonParser p, @Nullable DeserializationContext context) throws JacksonException {
+
+		Assert.notNull(p, "p must not be null");
+
 		return GeoPoint.toPoint(p.readValueAs(GeoPoint.class));
 	}
 }

src/main/java/org/springframework/data/elasticsearch/core/geo/GeoJsonGeometryCollection.java

@@ -19,6 +19,7 @@ import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 
+import org.jspecify.annotations.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -68,7 +69,7 @@ public class GeoJsonGeometryCollection implements GeoJson<Iterable<GeoJson<?>>>
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		if (this == o)
 			return true;
 		if (o == null || getClass() != o.getClass())

src/main/java/org/springframework/data/elasticsearch/core/geo/GeoJsonLineString.java

@@ -21,6 +21,7 @@ import java.util.Collections;
 import java.util.List;
 import java.util.stream.Collectors;
 
+import org.jspecify.annotations.Nullable;
 import org.springframework.data.geo.Point;
 import org.springframework.util.Assert;
 
@@ -122,7 +123,7 @@ public class GeoJsonLineString implements GeoJson<Iterable<Point>> {
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		if (this == o)
 			return true;
 		if (o == null || getClass() != o.getClass())

src/main/java/org/springframework/data/elasticsearch/core/geo/GeoJsonMultiLineString.java

@@ -21,6 +21,7 @@ import java.util.Collections;
 import java.util.List;
 import java.util.stream.Collectors;
 
+import org.jspecify.annotations.Nullable;
 import org.springframework.data.geo.Point;
 import org.springframework.util.Assert;
 
@@ -81,7 +82,7 @@ public class GeoJsonMultiLineString implements GeoJson<Iterable<GeoJsonLineStrin
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		if (this == o)
 			return true;
 		if (o == null || getClass() != o.getClass())

src/main/java/org/springframework/data/elasticsearch/core/geo/GeoJsonMultiPoint.java

@@ -21,6 +21,7 @@ import java.util.Collections;
 import java.util.List;
 import java.util.stream.Collectors;
 
+import org.jspecify.annotations.Nullable;
 import org.springframework.data.geo.Point;
 import org.springframework.util.Assert;
 
@@ -122,7 +123,7 @@ public class GeoJsonMultiPoint implements GeoJson<Iterable<Point>> {
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		if (this == o)
 			return true;
 		if (o == null || getClass() != o.getClass())

src/main/java/org/springframework/data/elasticsearch/core/geo/GeoJsonMultiPolygon.java

@@ -19,6 +19,7 @@ import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 
+import org.jspecify.annotations.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -62,7 +63,7 @@ public class GeoJsonMultiPolygon implements GeoJson<Iterable<GeoJsonPolygon>> {
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		if (this == o)
 			return true;
 		if (o == null || getClass() != o.getClass())

src/main/java/org/springframework/data/elasticsearch/core/geo/GeoJsonPoint.java

@@ -18,6 +18,7 @@ package org.springframework.data.elasticsearch.core.geo;
 import java.util.Arrays;
 import java.util.List;
 
+import org.jspecify.annotations.Nullable;
 import org.springframework.data.geo.Point;
 
 /**
@@ -89,7 +90,7 @@ public class GeoJsonPoint implements GeoJson<List<Double>> {
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		if (this == o)
 			return true;
 		if (o == null || getClass() != o.getClass())

src/main/java/org/springframework/data/elasticsearch/core/geo/GeoJsonPolygon.java

@@ -21,6 +21,7 @@ import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
 
+import org.jspecify.annotations.Nullable;
 import org.springframework.data.geo.Point;
 import org.springframework.util.Assert;
 
@@ -207,7 +208,7 @@ public class GeoJsonPolygon implements GeoJson<Iterable<GeoJsonLineString>> {
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		if (this == o)
 			return true;
 		if (o == null || getClass() != o.getClass())

src/main/java/org/springframework/data/elasticsearch/core/geo/GeoPoint.java

@@ -17,6 +17,7 @@ package org.springframework.data.elasticsearch.core.geo;
 
 import java.util.Objects;
 
+import org.jspecify.annotations.Nullable;
 import org.springframework.data.geo.Point;
 
 /**
@@ -63,7 +64,7 @@ public class GeoPoint {
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		if (this == o)
 			return true;
 		if (o == null || getClass() != o.getClass())

src/main/java/org/springframework/data/elasticsearch/core/geo/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.core.geo;

src/main/java/org/springframework/data/elasticsearch/core/index/AliasActionParameters.java

@@ -27,7 +27,7 @@ import org.springframework.util.Assert;
  */
 public class AliasActionParameters {
 	private final String[] indices;
-	@Nullable private final String[] aliases;
+	private final String @Nullable [] aliases;
 	@Nullable private final Query filterQuery;
 	@Nullable private final Class<?> filterQueryClass;
 	@Nullable private final Boolean isHidden;
@@ -36,7 +36,7 @@ public class AliasActionParameters {
 	@Nullable private final String indexRouting;
 	@Nullable private final String searchRouting;
 
-	private AliasActionParameters(String[] indices, @Nullable String[] aliases, @Nullable Boolean isHidden,
+	private AliasActionParameters(String[] indices, String @Nullable [] aliases, @Nullable Boolean isHidden,
 			@Nullable Boolean isWriteIndex, @Nullable String routing, @Nullable String indexRouting,
 			@Nullable String searchRouting, @Nullable Query filterQuery, @Nullable Class<?> filterQueryClass) {
 		this.indices = indices;
@@ -66,7 +66,7 @@ public class AliasActionParameters {
 		return indices;
 	}
 
-	public String@Nullable[] getAliases() {
+	public String @Nullable [] getAliases() {
 		return aliases;
 	}
 

src/main/java/org/springframework/data/elasticsearch/core/index/AliasActions.java

@@ -38,7 +38,7 @@ public class AliasActions {
 	 *
 	 * @param actions {@link AliasAction} elements
 	 */
-	public AliasActions(@Nullable AliasAction... actions) {
+	public AliasActions(AliasAction @Nullable... actions) {
 		add(actions);
 	}
 
@@ -52,10 +52,9 @@ public class AliasActions {
 	 * @param actions elements to add
 	 * @return this object
 	 */
-	public AliasActions add(@Nullable AliasAction... actions) {
+	public AliasActions add(AliasAction @Nullable... actions) {
 
 		if (actions != null) {
-			// noinspection NullableProblems
 			this.actions.addAll(Arrays.asList(actions));
 		}
 

src/main/java/org/springframework/data/elasticsearch/core/index/ComponentTemplateRequestData.java

@@ -40,7 +40,7 @@ public record ComponentTemplateRequestData(@Nullable Settings settings, @Nullabl
 		@Nullable private AliasActions aliasActions;
 		@Nullable private Boolean allowAutoCreate;
 
-		public Builder withSettings(Map<String, Object> settings) {
+		public Builder withSettings(Map<String, @Nullable Object> settings) {
 			this.settings = new Settings(settings);
 			return this;
 		}

src/main/java/org/springframework/data/elasticsearch/core/index/MappingBuilder.java

@@ -36,9 +36,7 @@ import java.util.stream.Collectors;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-import org.jspecify.annotations.NonNull;
 import org.jspecify.annotations.Nullable;
-
 import org.springframework.core.io.ClassPathResource;
 import org.springframework.data.annotation.Transient;
 import org.springframework.data.core.TypeInformation;
@@ -112,9 +110,15 @@ public class MappingBuilder {
 
 	protected final ElasticsearchConverter elasticsearchConverter;
 	private final ObjectMapper objectMapper = new ObjectMapper();
+	private final MappingParametersCustomizer customizer;
 
 	public MappingBuilder(ElasticsearchConverter elasticsearchConverter) {
+		this(elasticsearchConverter, MappingParameters::from);
+	}
+
+	public MappingBuilder(ElasticsearchConverter elasticsearchConverter, MappingParametersCustomizer customizer) {
 		this.elasticsearchConverter = elasticsearchConverter;
+		this.customizer = customizer;
 	}
 
 	/**
@@ -275,7 +279,7 @@ public class MappingBuilder {
 			writeTypeHintMapping(propertiesNode);
 
 			if (entity != null) {
-				entity.doWithProperties((PropertyHandler<@NonNull ElasticsearchPersistentProperty>) property -> {
+				entity.doWithProperties((PropertyHandler<ElasticsearchPersistentProperty>) property -> {
 					try {
 						if (property.isAnnotationPresent(Transient.class) || isInIgnoreFields(property, parentFieldAnnotation)) {
 							return;
@@ -589,7 +593,7 @@ public class MappingBuilder {
 		private void addFieldMappingParameters(ObjectNode fieldNode, Annotation annotation, boolean nestedOrObjectField)
 				throws IOException {
 
-			MappingParameters mappingParameters = MappingParameters.from(annotation);
+			MappingParameters mappingParameters = customizer.from(annotation);
 
 			if (!nestedOrObjectField && mappingParameters.isStore()) {
 				fieldNode.put(FIELD_PARAM_STORE, true);

src/main/java/org/springframework/data/elasticsearch/core/index/MappingParameters.java

@@ -34,7 +34,9 @@ import org.springframework.util.StringUtils;
 /**
  * A class to hold the mapping parameters that might be set on
  * {@link org.springframework.data.elasticsearch.annotations.Field } or
- * {@link org.springframework.data.elasticsearch.annotations.InnerField} annotation.
+ * {@link org.springframework.data.elasticsearch.annotations.InnerField} annotation. The class allows extensibility
+ * (non-final) to simplify mapping parameters customization, provided by
+ * {@link org.springframework.data.elasticsearch.core.index.MappingParametersCustomizer}.
  *
  * @author Peter-Josef Meisch
  * @author Aleksei Arsenev
@@ -42,9 +44,10 @@ import org.springframework.util.StringUtils;
  * @author Morgan Lutz
  * @author Sascha Woo
  * @author Haibo Liu
+ * @author Andriy Redko
  * @since 4.0
  */
-public final class MappingParameters {
+public class MappingParameters {
 
 	static final String FIELD_PARAM_COERCE = "coerce";
 	static final String FIELD_PARAM_COPY_TO = "copy_to";
@@ -86,7 +89,7 @@ public final class MappingParameters {
 
 	private final String analyzer;
 	private final boolean coerce;
-	@Nullable private final String[] copyTo;
+	private final String @Nullable [] copyTo;
 	private final DateFormat[] dateFormats;
 	private final String[] dateFormatPatterns;
 	private final boolean docValues;
@@ -137,7 +140,7 @@ public final class MappingParameters {
 		}
 	}
 
-	private MappingParameters(Field field) {
+	protected MappingParameters(Field field) {
 		index = field.index();
 		store = field.store();
 		fielddata = field.fielddata();
@@ -184,7 +187,7 @@ public final class MappingParameters {
 		eagerGlobalOrdinals = field.eagerGlobalOrdinals();
 	}
 
-	private MappingParameters(InnerField field) {
+	protected MappingParameters(InnerField field) {
 		index = field.index();
 		store = field.store();
 		fielddata = field.fielddata();
@@ -417,4 +420,132 @@ public final class MappingParameters {
 			objectNode.put(FIELD_PARAM_EAGER_GLOBAL_ORDINALS, eagerGlobalOrdinals);
 		}
 	}
+
+	protected String analyzer() {
+		return analyzer;
+	}
+
+	protected boolean coerce() {
+		return coerce;
+	}
+
+	protected String @Nullable [] copyTo() {
+		return copyTo;
+	}
+
+	protected DateFormat[] dateFormats() {
+		return dateFormats;
+	}
+
+	protected String[] dateFormatPatterns() {
+		return dateFormatPatterns;
+	}
+
+	protected boolean hasDocValues() {
+		return docValues;
+	}
+
+	protected boolean hasEagerGlobalOrdinals() {
+		return eagerGlobalOrdinals;
+	}
+
+	protected boolean isEnabled() {
+		return enabled;
+	}
+
+	protected boolean hasFielddata() {
+		return fielddata;
+	}
+
+	protected Integer ignoreAbove() {
+		return ignoreAbove;
+	}
+
+	protected boolean isIgnoreMalformed() {
+		return ignoreMalformed;
+	}
+
+	protected boolean isIndex() {
+		return index;
+	}
+
+	protected IndexOptions indexOptions() {
+		return indexOptions;
+	}
+
+	protected boolean isIndexPhrases() {
+		return indexPhrases;
+	}
+
+	protected IndexPrefixes indexPrefixes() {
+		return indexPrefixes;
+	}
+
+	protected String normalizer() {
+		return normalizer;
+	}
+
+	protected boolean hasNorms() {
+		return norms;
+	}
+
+	protected Integer maxShingleSize() {
+		return maxShingleSize;
+	}
+
+	protected String nullValue() {
+		return nullValue;
+	}
+
+	protected NullValueType nullValueType() {
+		return nullValueType;
+	}
+
+	protected Integer positionIncrementGap() {
+		return positionIncrementGap;
+	}
+
+	protected boolean positiveScoreImpact() {
+		return positiveScoreImpact;
+	}
+
+	protected Integer dims() {
+		return dims;
+	}
+
+	protected String elementType() {
+		return elementType;
+	}
+
+	protected KnnSimilarity knnSimilarity() {
+		return knnSimilarity;
+	}
+
+	protected KnnIndexOptions knnIndexOptions() {
+		return knnIndexOptions;
+	}
+
+	protected String searchAnalyzer() {
+		return searchAnalyzer;
+	}
+
+	protected double scalingFactor() {
+		return scalingFactor;
+	}
+
+	protected String similarity() {
+		return similarity;
+	}
+
+	protected TermVector termVector() {
+		return termVector;
+	}
+
+	protected FieldType type() {
+		return type;
+	}
+
+	protected String mappedTypeName() {
+		return mappedTypeName;
+	}
 }

src/main/java/org/springframework/data/elasticsearch/core/index/MappingParametersCustomizer.java

@@ -0,0 +1,36 @@
+/*
+ * Copyright 2026-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.springframework.data.elasticsearch.core.index;
+
+import java.lang.annotation.Annotation;
+
+/**
+ * Allows to customize {@link org.springframework.data.elasticsearch.core.index.MappingParameters} that are being
+ * emitted for each supported annotation. Needed by dependent projects like Spring-Data-Opensearch.
+ *
+ * @author Andriy Redko
+ * @since 6.1.0
+ */
+public interface MappingParametersCustomizer {
+	/**
+	 * Customize @link org.springframework.data.elasticsearch.core.index.MappingParameters} for each supported annotation.
+	 *
+	 * @param annotation supported annotation
+	 * @return customized @link org.springframework.data.elasticsearch.core.index.MappingParameters}
+	 */
+
+	MappingParameters from(Annotation annotation);
+}

src/main/java/org/springframework/data/elasticsearch/core/index/PutTemplateRequest.java

@@ -102,7 +102,7 @@ public class PutTemplateRequest {
 			this.indexPatterns = indexPatterns;
 		}
 
-		public TemplateRequestBuilder withSettings(Map<String, Object> settings) {
+		public TemplateRequestBuilder withSettings(Map<String, @Nullable Object> settings) {
 			this.settings = new Settings(settings);
 			return this;
 		}

src/main/java/org/springframework/data/elasticsearch/core/index/ReactiveMappingBuilder.java

@@ -31,6 +31,7 @@ import org.springframework.data.mapping.MappingException;
  * Subclass of {@link MappingBuilder} with specialized methods To inhibit blocking calls
  *
  * @author Peter-Josef Meisch
+ * @author Andriy Redko
  * @since 4.3
  */
 public class ReactiveMappingBuilder extends MappingBuilder {
@@ -39,6 +40,10 @@ public class ReactiveMappingBuilder extends MappingBuilder {
 		super(elasticsearchConverter);
 	}
 
+	public ReactiveMappingBuilder(ElasticsearchConverter elasticsearchConverter, MappingParametersCustomizer customizer) {
+		super(elasticsearchConverter, customizer);
+	}
+
 	@Override
 	public String buildPropertyMapping(Class<?> clazz) throws MappingException {
 		throw new UnsupportedOperationException(

src/main/java/org/springframework/data/elasticsearch/core/index/Settings.java

@@ -21,6 +21,7 @@ import java.util.Map;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
+import org.jspecify.annotations.Nullable;
 import org.springframework.data.elasticsearch.support.DefaultStringObjectMap;
 import org.springframework.util.Assert;
 
@@ -34,7 +35,7 @@ public class Settings extends DefaultStringObjectMap<Settings> {
 
 	public Settings() {}
 
-	public Settings(Map<String, Object> map) {
+	public Settings(Map<String, @Nullable Object> map) {
 		super(map);
 	}
 
@@ -54,7 +55,7 @@ public class Settings extends DefaultStringObjectMap<Settings> {
 	}
 
 	@Override
-	public Object get(Object key) {
+	public Object get(@Nullable Object key) {
 		return containsKey(key) ? super.get(key) : path(key.toString());
 	}
 
@@ -75,11 +76,11 @@ public class Settings extends DefaultStringObjectMap<Settings> {
 	 * taken from https://stackoverflow.com/a/29698326/4393565
 	 */
 	@SuppressWarnings("unchecked")
-	private static Map<?, ?> deepMerge(Map<String, Object> original, Map<String, Object> newMap) {
+	private static Map<?, ?> deepMerge(Map<String, @Nullable Object> original, Map<String, @Nullable Object> newMap) {
 		for (Object key : newMap.keySet()) {
 			if (newMap.get(key) instanceof Map && original.get(key) instanceof Map) {
-				Map<String, Object> originalChild = (Map<String, Object>) original.get(key);
-				Map<String, Object> newChild = (Map<String, Object>) newMap.get(key);
+				Map<String, @Nullable Object> originalChild = (Map<String, Object>) original.get(key);
+				Map<String, @Nullable Object> newChild = (Map<String, Object>) newMap.get(key);
 				original.put(key.toString(), deepMerge(originalChild, newChild));
 			} else if (newMap.get(key) instanceof List && original.get(key) instanceof List) {
 				List<Object> originalChild = (List<Object>) original.get(key);
@@ -112,9 +113,9 @@ public class Settings extends DefaultStringObjectMap<Settings> {
 	 * flattens a Map<String, Object> to a stream of Map.Entry objects where the keys are the dot separated concatenated
 	 * keys of sub map entries
 	 */
-	static private Stream<Map.Entry<String, Object>> doFlatten(Map.Entry<String, Object> entry) {
+	static private Stream<Map.Entry<String, @Nullable Object>> doFlatten(Map.Entry<String, @Nullable Object> entry) {
 
-		if (entry.getValue()instanceof Map<?, ?> nested) {
+		if (entry.getValue() instanceof Map<?, ?> nested) {
 
 			// noinspection unchecked
 			return nested.entrySet().stream() //

src/main/java/org/springframework/data/elasticsearch/core/index/TemplateData.java

@@ -91,7 +91,7 @@ public class TemplateData {
 			return this;
 		}
 
-		public TemplateDataBuilder withSettings(Map<String, Object> settings) {
+		public TemplateDataBuilder withSettings(Map<String, @Nullable Object> settings) {
 			this.settings = new Settings(settings);
 			return this;
 		}

src/main/java/org/springframework/data/elasticsearch/core/index/package-info.java

@@ -1,5 +1,18 @@
-/**
- * Classes related to Elasticsearch index management.
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
  */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.core.index;

src/main/java/org/springframework/data/elasticsearch/core/join/JoinField.java

@@ -64,7 +64,7 @@ public class JoinField<ID> {
 	}
 
 	@Override
-	public boolean equals(Object obj) {
+	public boolean equals(@Nullable Object obj) {
 		if (this == obj) {
 			return true;
 		}

src/main/java/org/springframework/data/elasticsearch/core/join/package-info.java

@@ -0,0 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
+@org.jspecify.annotations.NullMarked
+package org.springframework.data.elasticsearch.core.join;

src/main/java/org/springframework/data/elasticsearch/core/mapping/Alias.java

@@ -115,7 +115,7 @@ public class Alias {
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		if (this == o)
 			return true;
 		if (!(o instanceof Alias that))

src/main/java/org/springframework/data/elasticsearch/core/mapping/CreateIndexSettings.java

@@ -33,7 +33,7 @@ public class CreateIndexSettings {
 	private final IndexCoordinates indexCoordinates;
 	private final Set<Alias> aliases;
 
-	@Nullable private final Map<String, Object> settings;
+	@Nullable private final Map<String, @Nullable Object> settings;
 
 	@Nullable private final Document mapping;
 
@@ -58,7 +58,7 @@ public class CreateIndexSettings {
 	}
 
 	@Nullable
-	public Map<String, Object> getSettings() {
+	public Map<String, @Nullable Object> getSettings() {
 		return settings;
 	}
 
@@ -71,7 +71,7 @@ public class CreateIndexSettings {
 		private final IndexCoordinates indexCoordinates;
 		private final Set<Alias> aliases = new HashSet<>();
 
-		@Nullable private Map<String, Object> settings;
+		@Nullable private Map<String, @Nullable Object> settings;
 
 		@Nullable private Document mapping;
 
@@ -94,7 +94,7 @@ public class CreateIndexSettings {
 			return this;
 		}
 
-		public Builder withSettings(Map<String, Object> settings) {
+		public Builder withSettings(Map<String, @Nullable Object> settings) {
 			Assert.notNull(settings, "settings must not be null");
 			this.settings = settings;
 

src/main/java/org/springframework/data/elasticsearch/core/mapping/IndexCoordinates.java

@@ -17,6 +17,7 @@ package org.springframework.data.elasticsearch.core.mapping;
 
 import java.util.Arrays;
 
+import org.jspecify.annotations.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -55,7 +56,7 @@ public class IndexCoordinates {
 	 * @since 4.2
 	 */
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		if (this == o)
 			return true;
 		if (o == null || getClass() != o.getClass())

src/main/java/org/springframework/data/elasticsearch/core/mapping/SimpleElasticsearchPersistentEntity.java

@@ -23,9 +23,7 @@ import java.util.concurrent.atomic.AtomicReference;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-import org.jspecify.annotations.NonNull;
 import org.jspecify.annotations.Nullable;
-
 import org.springframework.core.annotation.AnnotatedElementUtils;
 import org.springframework.dao.InvalidDataAccessApiUsageException;
 import org.springframework.data.core.TypeInformation;
@@ -263,6 +261,7 @@ public class SimpleElasticsearchPersistentEntity<T> extends BasicPersistentEntit
 				throw new MappingException("@IndexedIndexName annotation must be put on String property");
 			}
 
+			// noinspection VariableNotUsedInsideIf
 			if (indexedIndexNameProperty != null) {
 				throw new MappingException(
 						"@IndexedIndexName annotation can only be put on one property in an entity");
@@ -301,7 +300,7 @@ public class SimpleElasticsearchPersistentEntity<T> extends BasicPersistentEntit
 
 		return fieldNamePropertyCache.computeIfAbsent(fieldName, key -> {
 			AtomicReference<@Nullable ElasticsearchPersistentProperty> propertyRef = new AtomicReference<>();
-			doWithProperties((PropertyHandler<@NonNull ElasticsearchPersistentProperty>) property -> {
+			doWithProperties((PropertyHandler<ElasticsearchPersistentProperty>) property -> {
 				if (key.equals(property.getFieldName())) {
 					propertyRef.set(property);
 				}
@@ -425,8 +424,7 @@ public class SimpleElasticsearchPersistentEntity<T> extends BasicPersistentEntit
 
 		try {
 			Expression expression = routingExpressions.computeIfAbsent(routing, PARSER::parseExpression);
-			ExpressionDependencies expressionDependencies = expression != null ? ExpressionDependencies.discover(expression)
-					: ExpressionDependencies.none();
+			ExpressionDependencies expressionDependencies = ExpressionDependencies.discover(expression);
 
 			EvaluationContext context = getEvaluationContext(null, expressionDependencies);
 			context.setVariable("entity", bean);

src/main/java/org/springframework/data/elasticsearch/core/mapping/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.core.mapping;

src/main/java/org/springframework/data/elasticsearch/core/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.core;

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

@@ -602,6 +602,7 @@ public class BaseQuery implements Query {
 				// searchForStream to work correctly (#3098) as there the page size defines what is
 				// returned in a single request, and the max result determines the total number of
 				// documents returned.
+				// noinspection DataFlowIssue maxResults is not null here, this is checked with isLimiting()
 				requestSize = Math.min(pageable.getPageSize(), getMaxResults());
 			}
 		} else if (pageable == UNSET_PAGE) {
@@ -622,6 +623,7 @@ public class BaseQuery implements Query {
 				// searchForStream to work correctly (#3098) as there the page size defines what is
 				// returned in a single request, and the max result determines the total number of
 				// documents returned.
+				// noinspection DataFlowIssue maxResults is not null here, this is checked with isLimiting()
 				requestSize = Math.min(INDEX_MAX_RESULT_WINDOW, getMaxResults());
 			}
 		}

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

@@ -97,7 +97,6 @@ public abstract class BaseQueryBuilder<Q extends BaseQuery, SELF extends BaseQue
 		return maxResults;
 	}
 
-	@Nullable
 	public Collection<String> getIds() {
 		return ids;
 	}
@@ -182,7 +181,7 @@ public abstract class BaseQueryBuilder<Q extends BaseQuery, SELF extends BaseQue
 	 * @since 6.1
 	 */
 	@Nullable
-	public Boolean getIncludeNamedQueriesScore(){
+	public Boolean getIncludeNamedQueriesScore() {
 		return includeNamedQueryScore;
 	}
 
@@ -393,7 +392,7 @@ public abstract class BaseQueryBuilder<Q extends BaseQuery, SELF extends BaseQue
 	/**
 	 * @since 6.1
 	 */
-	public SELF withIncludeNamedQueryScore (@Nullable Boolean namedQueryScore) {
+	public SELF withIncludeNamedQueryScore(@Nullable Boolean namedQueryScore) {
 		this.includeNamedQueryScore = namedQueryScore;
 		return self();
 	}

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

@@ -61,16 +61,16 @@ public class Criteria {
 	private float boost = Float.NaN;
 	private boolean negating = false;
 
-    // we cash this and recalculate when properties used in equals change
-    // see https://github.com/spring-projects/spring-data-elasticsearch/issues/3083
-    private int hashCode;
+	// we cache this and recalculate when properties used in equals change
+	// see https://github.com/spring-projects/spring-data-elasticsearch/issues/3083
+	private int hashCode;
 
-    private final CriteriaChain criteriaChain = new CriteriaChain();
-    private final Set<CriteriaEntry> queryCriteriaEntries = new LinkedHashSet<>();
-    private final Set<CriteriaEntry> filterCriteriaEntries = new LinkedHashSet<>();
-    private final Set<Criteria> subCriteria = new LinkedHashSet<>();
+	private final CriteriaChain criteriaChain = new CriteriaChain();
+	private final Set<CriteriaEntry> queryCriteriaEntries = new LinkedHashSet<>();
+	private final Set<CriteriaEntry> filterCriteriaEntries = new LinkedHashSet<>();
+	private final Set<Criteria> subCriteria = new LinkedHashSet<>();
 
-    // region criteria creation
+	// region criteria creation
 
 	/**
 	 * @return factory method to create an and-Criteria that is not bound to a field
@@ -89,8 +89,8 @@ public class Criteria {
 	}
 
 	public Criteria() {
-        recalculateHashCode();
-    }
+		recalculateHashCode();
+	}
 
 	/**
 	 * Creates a new Criteria with provided field name
@@ -113,7 +113,7 @@ public class Criteria {
 
 		this.field = field;
 		this.criteriaChain.add(this);
-        recalculateHashCode();
+		recalculateHashCode();
 	}
 
 	/**
@@ -143,7 +143,7 @@ public class Criteria {
 		this.field = field;
 		this.criteriaChain.addAll(criteriaChain);
 		this.criteriaChain.add(this);
-        recalculateHashCode();
+		recalculateHashCode();
 	}
 
 	/**
@@ -197,7 +197,7 @@ public class Criteria {
 	 */
 	public Criteria not() {
 		this.negating = true;
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -216,7 +216,7 @@ public class Criteria {
 		Assert.isTrue(boost >= 0, "boost must not be negative");
 
 		this.boost = boost;
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -274,7 +274,7 @@ public class Criteria {
 		Assert.notNull(criteria, "Cannot chain 'null' criteria.");
 
 		this.criteriaChain.add(criteria);
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -289,7 +289,7 @@ public class Criteria {
 		Assert.notNull(criterias, "Cannot chain 'null' criterias.");
 
 		this.criteriaChain.addAll(Arrays.asList(criterias));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -332,7 +332,7 @@ public class Criteria {
 		orCriteria.subCriteria.addAll(criteria.subCriteria);
 		orCriteria.boost = criteria.boost;
 		orCriteria.negating = criteria.isNegating();
-        orCriteria.recalculateHashCode();
+		orCriteria.recalculateHashCode();
 		return orCriteria;
 	}
 
@@ -348,7 +348,7 @@ public class Criteria {
 		Assert.notNull(criteria, "criteria must not be null");
 
 		subCriteria.add(criteria);
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -363,7 +363,7 @@ public class Criteria {
 	 */
 	public Criteria is(Object o) {
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.EQUALS, o));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -375,7 +375,7 @@ public class Criteria {
 	 */
 	public Criteria exists() {
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.EXISTS));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -394,7 +394,7 @@ public class Criteria {
 		}
 
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.BETWEEN, new Object[] { lowerBound, upperBound }));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -410,7 +410,7 @@ public class Criteria {
 
 		assertNoBlankInWildcardQuery(s, false, true);
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.STARTS_WITH, s));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -427,7 +427,7 @@ public class Criteria {
 
 		assertNoBlankInWildcardQuery(s, true, true);
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.CONTAINS, s));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -444,7 +444,7 @@ public class Criteria {
 
 		assertNoBlankInWildcardQuery(s, true, false);
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.ENDS_WITH, s));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -472,7 +472,7 @@ public class Criteria {
 		Assert.notNull(values, "Collection of 'in' values must not be null");
 
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.IN, values));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -499,7 +499,7 @@ public class Criteria {
 		Assert.notNull(values, "Collection of 'NotIn' values must not be null");
 
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.NOT_IN, values));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -512,7 +512,7 @@ public class Criteria {
 	 */
 	public Criteria expression(String s) {
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.EXPRESSION, s));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -524,7 +524,7 @@ public class Criteria {
 	 */
 	public Criteria fuzzy(String s) {
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.FUZZY, s));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -539,7 +539,7 @@ public class Criteria {
 		Assert.notNull(upperBound, "upperBound must not be null");
 
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.LESS_EQUAL, upperBound));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -554,7 +554,7 @@ public class Criteria {
 		Assert.notNull(upperBound, "upperBound must not be null");
 
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.LESS, upperBound));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -569,7 +569,7 @@ public class Criteria {
 		Assert.notNull(lowerBound, "lowerBound must not be null");
 
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.GREATER_EQUAL, lowerBound));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -584,7 +584,7 @@ public class Criteria {
 		Assert.notNull(lowerBound, "lowerBound must not be null");
 
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.GREATER, lowerBound));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -601,7 +601,7 @@ public class Criteria {
 		Assert.notNull(value, "value must not be null");
 
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.MATCHES, value));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -618,7 +618,7 @@ public class Criteria {
 		Assert.notNull(value, "value must not be null");
 
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.MATCHES_ALL, value));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -631,7 +631,7 @@ public class Criteria {
 	public Criteria empty() {
 
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.EMPTY));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -644,7 +644,7 @@ public class Criteria {
 	public Criteria notEmpty() {
 
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.NOT_EMPTY));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -660,7 +660,7 @@ public class Criteria {
 		Assert.notNull(value, "value must not be null");
 
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.REGEXP, value));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -679,7 +679,7 @@ public class Criteria {
 		Assert.notNull(boundingBox, "boundingBox value for boundedBy criteria must not be null");
 
 		filterCriteriaEntries.add(new CriteriaEntry(OperationKey.BBOX, new Object[] { boundingBox }));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -696,7 +696,7 @@ public class Criteria {
 
 		filterCriteriaEntries
 				.add(new CriteriaEntry(OperationKey.BBOX, new Object[] { boundingBox.getFirst(), boundingBox.getSecond() }));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -714,7 +714,7 @@ public class Criteria {
 
 		filterCriteriaEntries
 				.add(new CriteriaEntry(OperationKey.BBOX, new Object[] { topLeftGeohash, bottomRightGeohash }));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -731,7 +731,7 @@ public class Criteria {
 		Assert.notNull(bottomRightPoint, "bottomRightPoint must not be null");
 
 		filterCriteriaEntries.add(new CriteriaEntry(OperationKey.BBOX, new Object[] { topLeftPoint, bottomRightPoint }));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -749,7 +749,7 @@ public class Criteria {
 
 		filterCriteriaEntries.add(new CriteriaEntry(OperationKey.BBOX,
 				new Object[] { GeoPoint.fromPoint(topLeftPoint), GeoPoint.fromPoint(bottomRightPoint) }));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -767,7 +767,7 @@ public class Criteria {
 		Assert.notNull(location, "Distance value for near criteria must not be null");
 
 		filterCriteriaEntries.add(new CriteriaEntry(OperationKey.WITHIN, new Object[] { location, distance }));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -784,7 +784,7 @@ public class Criteria {
 		Assert.notNull(location, "Distance value for near criteria must not be null");
 
 		filterCriteriaEntries.add(new CriteriaEntry(OperationKey.WITHIN, new Object[] { location, distance }));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -801,7 +801,7 @@ public class Criteria {
 		Assert.isTrue(StringUtils.hasLength(geoLocation), "geoLocation value must not be null");
 
 		filterCriteriaEntries.add(new CriteriaEntry(OperationKey.WITHIN, new Object[] { geoLocation, distance }));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -816,7 +816,7 @@ public class Criteria {
 		Assert.notNull(geoShape, "geoShape must not be null");
 
 		filterCriteriaEntries.add(new CriteriaEntry(OperationKey.GEO_INTERSECTS, geoShape));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -831,7 +831,7 @@ public class Criteria {
 		Assert.notNull(geoShape, "geoShape must not be null");
 
 		filterCriteriaEntries.add(new CriteriaEntry(OperationKey.GEO_IS_DISJOINT, geoShape));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -845,7 +845,7 @@ public class Criteria {
 		Assert.notNull(geoShape, "geoShape must not be null");
 
 		filterCriteriaEntries.add(new CriteriaEntry(OperationKey.GEO_WITHIN, geoShape));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -859,7 +859,7 @@ public class Criteria {
 		Assert.notNull(geoShape, "geoShape must not be null");
 
 		filterCriteriaEntries.add(new CriteriaEntry(OperationKey.GEO_CONTAINS, geoShape));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -873,7 +873,7 @@ public class Criteria {
 		Assert.notNull(query, "has_child query must not be null.");
 
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.HAS_CHILD, query));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 
@@ -887,7 +887,7 @@ public class Criteria {
 		Assert.notNull(query, "has_parent query must not be null.");
 
 		queryCriteriaEntries.add(new CriteriaEntry(OperationKey.HAS_PARENT, query));
-        recalculateHashCode();
+		recalculateHashCode();
 		return this;
 	}
 	// endregion
@@ -909,7 +909,7 @@ public class Criteria {
 
 	// region equals/hashcode
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		if (this == o)
 			return true;
 		if (o == null || getClass() != o.getClass())
@@ -937,19 +937,19 @@ public class Criteria {
 		return hashCode;
 	}
 
-    private void recalculateHashCode() {
-        int result = field != null ? field.hashCode() : 0;
-        result = 31 * result + (boost != +0.0f ? Float.floatToIntBits(boost) : 0);
-        result = 31 * result + (negating ? 1 : 0);
-        // the criteriaChain contains "this" object, so we need to filter it out
-        // to avoid a stackoverflow here, because the hashcode implementation
-        // uses the element's hashcodes
-        result = 31 * result + criteriaChain.filter(this).hashCode();
-        result = 31 * result + queryCriteriaEntries.hashCode();
-        result = 31 * result + filterCriteriaEntries.hashCode();
-        result = 31 * result + subCriteria.hashCode();
-        this.hashCode = result;
-    }
+	private void recalculateHashCode() {
+		int result = field != null ? field.hashCode() : 0;
+		result = 31 * result + (boost != +0.0f ? Float.floatToIntBits(boost) : 0);
+		result = 31 * result + (negating ? 1 : 0);
+		// the criteriaChain contains "this" object, so we need to filter it out
+		// to avoid a stackoverflow here, because the hashcode implementation
+		// uses the element's hashcodes
+		result = 31 * result + criteriaChain.filter(this).hashCode();
+		result = 31 * result + queryCriteriaEntries.hashCode();
+		result = 31 * result + filterCriteriaEntries.hashCode();
+		result = 31 * result + subCriteria.hashCode();
+		this.hashCode = result;
+	}
 	// endregion
 
 	@Override
@@ -1141,7 +1141,7 @@ public class Criteria {
 		}
 
 		@Override
-		public boolean equals(Object o) {
+		public boolean equals(@Nullable Object o) {
 			if (this == o)
 				return true;
 			if (o == null || getClass() != o.getClass())

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

@@ -354,7 +354,6 @@ public class DeleteQuery {
 		return version;
 	}
 
-	@Nullable
 	public Query getQuery() {
 		return query;
 	}
@@ -648,6 +647,7 @@ public class DeleteQuery {
 			return this;
 		}
 
+		@SuppressWarnings("VariableNotUsedInsideIf")
 		public DeleteQuery build() {
 			if (luceneQuery == null) {
 				if (defaultField != null) {

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

@@ -29,14 +29,14 @@ import org.springframework.util.Assert;
 public class FetchSourceFilter implements SourceFilter {
 
 	@Nullable private final Boolean fetchSource;
-	@Nullable private final String[] includes;
-	@Nullable private final String[] excludes;
+	private final String @Nullable [] includes;
+	private final String @Nullable [] excludes;
 
 	/**
 	 * @since 5.2
 	 */
-	public static SourceFilter of(@Nullable Boolean fetchSource, @Nullable final String[] includes,
-			@Nullable final String[] excludes) {
+	public static SourceFilter of(@Nullable Boolean fetchSource, final String @Nullable [] includes,
+			final String @Nullable [] excludes) {
 		return new FetchSourceFilter(fetchSource, includes, excludes);
 	}
 
@@ -50,25 +50,25 @@ public class FetchSourceFilter implements SourceFilter {
 		return builderFunction.apply(new FetchSourceFilterBuilder()).build();
 	}
 
-	public FetchSourceFilter(@Nullable Boolean fetchSource, @Nullable final String[] includes,
-			@Nullable final String[] excludes) {
+	public FetchSourceFilter(@Nullable Boolean fetchSource, final String @Nullable [] includes,
+			final String @Nullable [] excludes) {
 		this.fetchSource = fetchSource;
 		this.includes = includes;
 		this.excludes = excludes;
 	}
 
 	@Override
-	public Boolean fetchSource() {
+	public @Nullable Boolean fetchSource() {
 		return fetchSource;
 	}
 
 	@Override
-	public @Nullable String[] getIncludes() {
+	public String @Nullable [] getIncludes() {
 		return includes;
 	}
 
 	@Override
-	public @Nullable String[] getExcludes() {
+	public String @Nullable [] getExcludes() {
 		return excludes;
 	}
 }

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

@@ -43,7 +43,7 @@ public class GeoDistanceOrder extends Order {
 	}
 
 	private GeoDistanceOrder(String property, GeoPoint geoPoint, Sort.Direction direction, DistanceType distanceType,
-			Mode mode, String unit, Boolean ignoreUnmapped) {
+			@Nullable Mode mode, String unit, Boolean ignoreUnmapped) {
 		super(direction, property, mode);
 		this.geoPoint = geoPoint;
 		this.distanceType = distanceType;
@@ -59,7 +59,7 @@ public class GeoDistanceOrder extends Order {
 		return distanceType;
 	}
 
-	public Mode getMode() {
+	public @Nullable Mode getMode() {
 		return mode;
 	}
 

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

@@ -83,7 +83,7 @@ public class SimpleField implements Field {
 	}
 
 	@Override
-	public boolean equals(Object o) {
+	public boolean equals(@Nullable Object o) {
 		if (this == o)
 			return true;
 		if (!(o instanceof SimpleField that))

src/main/java/org/springframework/data/elasticsearch/core/query/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.core.query;

src/main/java/org/springframework/data/elasticsearch/core/query/types/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.core.query.types;

src/main/java/org/springframework/data/elasticsearch/core/reindex/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.core.reindex;

src/main/java/org/springframework/data/elasticsearch/core/routing/DefaultRoutingResolver.java

@@ -37,7 +37,7 @@ public class DefaultRoutingResolver implements RoutingResolver {
 	}
 
 	@Override
-	public String getRouting() {
+	public @Nullable String getRouting() {
 		return null;
 	}
 

src/main/java/org/springframework/data/elasticsearch/core/routing/package-info.java

@@ -1,5 +1,18 @@
-/**
- * classes/interfaces for specification and implementation of Elasticsearch routing.
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
  */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.core.routing;

src/main/java/org/springframework/data/elasticsearch/core/script/package-info.java

@@ -1,6 +1,18 @@
-/**
- * Classes and interfaces to access to script API of Elasticsearch
- * (https://www.elastic.co/guide/en/elasticsearch/reference/8.5/script-apis.html).
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
  */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.core.script;

src/main/java/org/springframework/data/elasticsearch/core/sql/SqlResponse.java

@@ -25,7 +25,6 @@ import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 
-import org.jspecify.annotations.NonNull;
 import org.jspecify.annotations.Nullable;
 
 /**
@@ -110,7 +109,6 @@ public class SqlResponse {
 			return new Builder();
 		}
 
-		@NonNull
 		@Override
 		public Iterator<Map.Entry<Column, JsonValue>> iterator() {
 			return row.entrySet().iterator();

src/main/java/org/springframework/data/elasticsearch/core/sql/package-info.java

@@ -1,5 +1,18 @@
-/**
- * Classes and interfaces to access to SQL API of Elasticsearch.
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
  */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.core.sql;

src/main/java/org/springframework/data/elasticsearch/core/suggest/response/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.core.suggest.response;

src/main/java/org/springframework/data/elasticsearch/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch;

src/main/java/org/springframework/data/elasticsearch/repository/ElasticsearchRepository.java

@@ -44,7 +44,7 @@ public interface ElasticsearchRepository<T, ID> extends PagingAndSortingReposito
 	 * @param pageable , must not be {@literal null}
 	 * @return
 	 */
-	Page<T> searchSimilar(T entity, @Nullable String[] fields, Pageable pageable);
+	Page<T> searchSimilar(T entity, String @Nullable [] fields, Pageable pageable);
 
 	/**
 	 * @since 5.2

src/main/java/org/springframework/data/elasticsearch/repository/aot/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.repository.aot;

src/main/java/org/springframework/data/elasticsearch/repository/cdi/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.repository.cdi;

src/main/java/org/springframework/data/elasticsearch/repository/config/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.repository.config;

src/main/java/org/springframework/data/elasticsearch/repository/package-info.java

@@ -1,5 +1,18 @@
-/**
- * infrastructure to define the Elasticsearch mapping for an index.
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
  */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.repository;

src/main/java/org/springframework/data/elasticsearch/repository/query/AbstractElasticsearchRepositoryQuery.java

@@ -15,6 +15,8 @@
  */
 package org.springframework.data.elasticsearch.repository.query;
 
+import java.util.Objects;
+
 import org.jspecify.annotations.Nullable;
 import org.springframework.data.domain.PageRequest;
 import org.springframework.data.elasticsearch.core.ElasticsearchOperations;
@@ -82,13 +84,17 @@ public abstract class AbstractElasticsearchRepositoryQuery implements Repository
 	protected abstract boolean isExistsQuery();
 
 	@Override
-	public Object execute(Object[] parameters) {
+	public Object execute(@Nullable Object[] parameters) {
 
-		ElasticsearchParametersParameterAccessor parameterAccessor = getParameterAccessor(parameters);
+		// need this additional var, otherwise the code analysis does not recognize
+		// that parameters is not null after the check
+		var parametersNN = Objects.requireNonNull(parameters, "parameters must not be null");
+
+		ElasticsearchParametersParameterAccessor parameterAccessor = getParameterAccessor(parametersNN);
 		ResultProcessor resultProcessor = queryMethod.getResultProcessor().withDynamicProjection(parameterAccessor);
 		Class<?> clazz = resultProcessor.getReturnedType().getDomainType();
 
-		Query query = createQuery(parameters);
+		Query query = createQuery(parametersNN);
 
 		IndexCoordinates index = parameterAccessor
 				.getIndexCoordinates(elasticsearchOperations.getIndexCoordinatesFor(clazz));

src/main/java/org/springframework/data/elasticsearch/repository/query/AbstractReactiveElasticsearchRepositoryQuery.java

@@ -18,6 +18,9 @@ package org.springframework.data.elasticsearch.repository.query;
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
 
+import java.util.Objects;
+
+import org.jspecify.annotations.Nullable;
 import org.reactivestreams.Publisher;
 import org.springframework.core.convert.converter.Converter;
 import org.springframework.data.elasticsearch.core.ReactiveElasticsearchOperations;
@@ -72,10 +75,12 @@ abstract class AbstractReactiveElasticsearchRepositoryQuery implements Repositor
 	 * @see org.springframework.data.repository.query.RepositoryQuery#execute(java.lang.Object[])
 	 */
 	@Override
-	public Object execute(Object[] parameters) {
+	public Object execute(@Nullable Object[] parameters) {
 
-		Object result = queryMethod.hasReactiveWrapperParameter() ? executeDeferred(parameters)
-				: execute(new ReactiveElasticsearchParametersParameterAccessor(queryMethod, parameters));
+		var parametersNN = Objects.requireNonNull(parameters, "parameters must not be null");
+
+		Object result = queryMethod.hasReactiveWrapperParameter() ? executeDeferred(parametersNN)
+				: execute(new ReactiveElasticsearchParametersParameterAccessor(queryMethod, parametersNN));
 		return queryMethod.isNotSearchHitMethod() ? SearchHitSupport.unwrapSearchHits(result) : result;
 	}
 
@@ -98,7 +103,7 @@ abstract class AbstractReactiveElasticsearchRepositoryQuery implements Repositor
 		Class<?> domainType = returnedType.getDomainType();
 		Class<?> typeToRead = returnedType.getTypeToRead();
 
-		if (SearchHit.class.isAssignableFrom(typeToRead)) {
+		if (typeToRead != null && SearchHit.class.isAssignableFrom(typeToRead)) {
 			typeToRead = queryMethod.unwrappedReturnType;
 		}
 
@@ -145,9 +150,10 @@ abstract class AbstractReactiveElasticsearchRepositoryQuery implements Repositor
 					.map(count -> count > 0);
 		} else if (queryMethod.isCollectionQuery()) {
 			return (query, type, targetType, indexCoordinates) -> operations.search(query.setPageable(accessor.getPageable()),
-					type, targetType, indexCoordinates);
+					type, Objects.requireNonNull(targetType), indexCoordinates);
 		} else {
-			return operations::search;
+			return (query, type, targetType, index) -> operations.search(query, type, Objects.requireNonNull(targetType),
+					index);
 		}
 	}
 

src/main/java/org/springframework/data/elasticsearch/repository/query/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.repository.query;

src/main/java/org/springframework/data/elasticsearch/repository/query/parser/package-info.java

@@ -1,2 +1,18 @@
+/*
+ * Copyright 2022-present the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.
+ */
+
 @org.jspecify.annotations.NullMarked
 package org.springframework.data.elasticsearch.repository.query.parser;