Upgrade to Jackson 3

pom.xml

@@ -5,7 +5,7 @@
 
 	<groupId>org.springframework.data</groupId>
 	<artifactId>spring-data-commons</artifactId>
-	<version>4.0.0-SNAPSHOT</version>
+	<version>4.0.0-GH-3292-SNAPSHOT</version>
 
 	<name>Spring Data Core</name>
 	<description>Core Spring concepts underpinning every Spring Data module.</description>
@@ -70,6 +70,11 @@
 			<artifactId>jackson-databind</artifactId>
 			<optional>true</optional>
 		</dependency>
+		<dependency>
+			<groupId>tools.jackson.core</groupId>
+			<artifactId>jackson-databind</artifactId>
+			<optional>true</optional>
+		</dependency>
 		<dependency>
 			<groupId>org.springframework</groupId>
 			<artifactId>spring-web</artifactId>

src/main/antora/modules/ROOT/pages/repositories/core-extensions-web.adoc

@@ -290,9 +290,9 @@ By default, the assembler points to the controller method it was invoked in, but
 == Spring Data Jackson Modules
 
 The core module, and some of the store specific ones, ship with a set of Jackson Modules for types, like `org.springframework.data.geo.Distance` and `org.springframework.data.geo.Point`, used by the Spring Data domain. +
-Those Modules are imported once xref:repositories/core-extensions.adoc#core.web[web support] is enabled and `com.fasterxml.jackson.databind.ObjectMapper` is available.
+Those modules are imported once xref:repositories/core-extensions.adoc#core.web[web support] is enabled and `tools.jackson.databind.ObjectMapper` is available.
 
-During initialization `SpringDataJacksonModules`, like the `SpringDataJacksonConfiguration`, get picked up by the infrastructure, so that the declared ``com.fasterxml.jackson.databind.Module``s are made available to the Jackson `ObjectMapper`.
+During initialization `SpringDataJackson3Modules`, like the `SpringDataJackson3Configuration`, get picked up by the infrastructure, so that the declared ``tools.jackson.databind.JacksonModule``s are made available to the Jackson `ObjectMapper`.
 
 Data binding mixins for the following domain types are registered by the common infrastructure.
 
@@ -306,10 +306,15 @@ org.springframework.data.geo.Polygon
 
 [NOTE]
 ====
-The individual module may provide additional `SpringDataJacksonModules`. +
+The individual module may provide additional `SpringDataJackson3Modules`. +
 Please refer to the store specific section for more details.
 ====
 
+[NOTE]
+====
+Jackson 2 support is deprecated and will be removed in a future release.
+====
+
 [[core.web.binding]]
 == Web Databinding Support
 
@@ -341,7 +346,7 @@ Nested projections are supported as described in xref:repositories/projections.a
 If the method returns a complex, non-interface type, a Jackson `ObjectMapper` is used to map the final value.
 
 For Spring MVC, the necessary converters are registered automatically as soon as `@EnableSpringDataWebSupport` is active and the required dependencies are available on the classpath.
-For usage with `RestTemplate`, register a `ProjectingJackson2HttpMessageConverter` (JSON) or `XmlBeamHttpMessageConverter` manually.
+For usage with `RestTemplate`, register a `ProjectingJacksonHttpMessageConverter` (JSON) or `XmlBeamHttpMessageConverter` manually.
 
 For more information, see the https://github.com/spring-projects/spring-data-examples/tree/main/web/projection[web projection example] in the canonical https://github.com/spring-projects/spring-data-examples[Spring Data Examples repository].
 

src/main/java/org/springframework/data/geo/GeoJacksonModule.java

@@ -0,0 +1,80 @@
+/*
+ * Copyright 2014-2025 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.geo;
+
+import tools.jackson.core.Version;
+import tools.jackson.databind.annotation.JsonDeserialize;
+import tools.jackson.databind.module.SimpleModule;
+
+import java.io.Serial;
+import java.util.List;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+/**
+ * Custom module to deserialize the geo-spatial value objects using Jackson 3.
+ *
+ * @author Oliver Gierke
+ * @author Mark Paluch
+ * @since 4.0
+ */
+@SuppressWarnings("unused")
+public class GeoJacksonModule extends SimpleModule {
+
+	private static final @Serial long serialVersionUID = 1L;
+
+	/**
+	 * Creates a new {@link GeoJacksonModule} registering mixins for common geo-spatial types.
+	 */
+	public GeoJacksonModule() {
+
+		super("Spring Data Geo Mixins", new Version(1, 0, 0, null, "org.springframework.data", "spring-data-commons-geo"));
+
+		setMixInAnnotation(Distance.class, DistanceMixin.class);
+		setMixInAnnotation(Point.class, PointMixin.class);
+		setMixInAnnotation(Box.class, BoxMixin.class);
+		setMixInAnnotation(Circle.class, CircleMixin.class);
+		setMixInAnnotation(Polygon.class, PolygonMixin.class);
+	}
+
+	@JsonIgnoreProperties("unit")
+	static abstract class DistanceMixin {
+
+		DistanceMixin(@JsonProperty("value") double value,
+				@JsonProperty("metric") @JsonDeserialize(as = Metrics.class) Metric metic) {}
+
+		@JsonIgnore
+		abstract double getNormalizedValue();
+	}
+
+	static abstract class PointMixin {
+		PointMixin(@JsonProperty("x") double x, @JsonProperty("y") double y) {}
+	}
+
+	static abstract class CircleMixin {
+		CircleMixin(@JsonProperty("center") Point center, @JsonProperty("radius") Distance radius) {}
+	}
+
+	static abstract class BoxMixin {
+		BoxMixin(@JsonProperty("first") Point first, @JsonProperty("second") Point point) {}
+	}
+
+	static abstract class PolygonMixin {
+		PolygonMixin(@JsonProperty("points") List<Point> points) {}
+	}
+}

src/main/java/org/springframework/data/geo/GeoModule.java

@@ -30,8 +30,10 @@
  *
  * @author Oliver Gierke
  * @since 1.8
+ * @deprecated since 4.0, use {@link GeoJacksonModule} instead.
  */
 @SuppressWarnings("unused")
+@Deprecated(since = "4.0", forRemoval = true)
 public class GeoModule extends SimpleModule {
 
 	private static final @Serial long serialVersionUID = 1L;

src/main/java/org/springframework/data/repository/init/Jackson2RepositoryPopulatorFactoryBean.java

@@ -27,7 +27,9 @@
  * @author Oliver Gierke
  * @author Christoph Strobl
  * @since 1.6
+ * @deprecated since 4.0, in favor of {@link JacksonRepositoryPopulatorFactoryBean}.
  */
+@Deprecated(since = "4.0", forRemoval = true)
 public class Jackson2RepositoryPopulatorFactoryBean extends AbstractRepositoryPopulatorFactoryBean {
 
 	private @Nullable ObjectMapper mapper;

src/main/java/org/springframework/data/repository/init/Jackson2ResourceReader.java

@@ -40,7 +40,9 @@
  * @author Mark Paluch
  * @author Johannes Englmeier
  * @since 1.6
+ * @deprecated since 4.0, in favor of {@link JacksonResourceReader}.
  */
+@Deprecated(since = "4.0", forRemoval = true)
 public class Jackson2ResourceReader implements ResourceReader {
 
 	private static final String DEFAULT_TYPE_KEY = "_class";

src/main/java/org/springframework/data/repository/init/JacksonRepositoryPopulatorFactoryBean.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2025 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.repository.init;
+
+import tools.jackson.databind.ObjectMapper;
+
+import org.jspecify.annotations.Nullable;
+
+import org.springframework.beans.factory.FactoryBean;
+
+/**
+ * {@link FactoryBean} to set up a {@link ResourceReaderRepositoryPopulator} with a {@link JacksonResourceReader}.
+ *
+ * @author Mark Paluch
+ * @author Oliver Gierke
+ * @author Christoph Strobl
+ * @since 4.0
+ */
+public class JacksonRepositoryPopulatorFactoryBean extends AbstractRepositoryPopulatorFactoryBean {
+
+	private @Nullable ObjectMapper mapper;
+
+	/**
+	 * Configures the {@link ObjectMapper} to be used.
+	 *
+	 * @param mapper can be {@literal null}.
+	 */
+	public void setMapper(@Nullable ObjectMapper mapper) {
+		this.mapper = mapper;
+	}
+
+	@Override
+	protected ResourceReader getResourceReader() {
+		return mapper == null ? new JacksonResourceReader() : new JacksonResourceReader(mapper);
+	}
+}

src/main/java/org/springframework/data/repository/init/JacksonResourceReader.java

@@ -0,0 +1,123 @@
+/*
+ * Copyright 2013-2025 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.repository.init;
+
+import tools.jackson.databind.DeserializationFeature;
+import tools.jackson.databind.JsonNode;
+import tools.jackson.databind.ObjectMapper;
+import tools.jackson.databind.json.JsonMapper;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+
+import org.jspecify.annotations.Nullable;
+
+import org.springframework.core.io.Resource;
+import org.springframework.util.Assert;
+import org.springframework.util.ClassUtils;
+
+/**
+ * A {@link ResourceReader} using Jackson to read JSON into objects.
+ *
+ * @author Oliver Gierke
+ * @author Christoph Strobl
+ * @author Mark Paluch
+ * @author Johannes Englmeier
+ * @since 4.0
+ */
+public class JacksonResourceReader implements ResourceReader {
+
+	private static final String DEFAULT_TYPE_KEY = "_class";
+	private static final ObjectMapper DEFAULT_MAPPER = JsonMapper.builder()
+			.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false).build();
+
+	private final ObjectMapper mapper;
+	private String typeKey = DEFAULT_TYPE_KEY;
+
+	/**
+	 * Creates a new {@link JacksonResourceReader}.
+	 */
+	public JacksonResourceReader() {
+		this(DEFAULT_MAPPER);
+	}
+
+	/**
+	 * Creates a new {@link JacksonResourceReader} using the given {@link ObjectMapper}.
+	 *
+	 * @param mapper
+	 */
+	public JacksonResourceReader(ObjectMapper mapper) {
+		this.mapper = mapper;
+	}
+
+	/**
+	 * Configures the JSON document's key to look up the type to instantiate the object. Defaults to
+	 * {@link JacksonResourceReader#DEFAULT_TYPE_KEY}.
+	 *
+	 * @param typeKey
+	 */
+	public void setTypeKey(@Nullable String typeKey) {
+		this.typeKey = typeKey == null ? DEFAULT_TYPE_KEY : typeKey;
+	}
+
+	@Override
+	public Object readFrom(Resource resource, @Nullable ClassLoader classLoader) throws Exception {
+
+		Assert.notNull(resource, "Resource must not be null");
+
+		InputStream stream = resource.getInputStream();
+		JsonNode node = mapper.readerFor(JsonNode.class).readTree(stream);
+
+		if (node.isArray()) {
+
+			Iterator<JsonNode> elements = node.iterator();
+			List<Object> result = new ArrayList<>();
+
+			while (elements.hasNext()) {
+				JsonNode element = elements.next();
+				result.add(readSingle(element, classLoader));
+			}
+
+			return result;
+		}
+
+		return readSingle(node, classLoader);
+	}
+
+	/**
+	 * Reads the given {@link JsonNode} into an instance of the type encoded in it using the configured type key.
+	 *
+	 * @param node must not be {@literal null}.
+	 * @param classLoader can be {@literal null}.
+	 * @return
+	 */
+	private Object readSingle(JsonNode node, @Nullable ClassLoader classLoader) throws IOException {
+
+		JsonNode typeNode = node.findValue(typeKey);
+
+		if (typeNode == null) {
+			throw new IllegalArgumentException(String.format("Could not find type for type key '%s'", typeKey));
+		}
+
+		String typeName = typeNode.asString();
+		Class<?> type = ClassUtils.resolveClassName(typeName, classLoader);
+
+		return mapper.readerFor(type).readValue(node);
+	}
+}

src/main/java/org/springframework/data/web/JsonProjectingMethodInterceptorFactory.java

@@ -131,18 +131,27 @@ private static boolean hasJsonPathAnnotation(Class<?> type) {
 		return false;
 	}
 
-	private static class InputMessageProjecting implements MethodInterceptor {
-
-		private final DocumentContext context;
-
-		public InputMessageProjecting(DocumentContext context) {
-			this.context = context;
-		}
+	private record InputMessageProjecting(DocumentContext context) implements MethodInterceptor {
 
 		@Override
 		public @Nullable Object invoke(MethodInvocation invocation) throws Throwable {
 
 			Method method = invocation.getMethod();
+
+			switch (method.getName()) {
+				case "equals" -> {
+					// Only consider equal when proxies are identical.
+					return (invocation.getThis() == invocation.getArguments()[0]);
+				}
+				case "hashCode" -> {
+					// Use hashCode of EntityManager proxy.
+					return context.hashCode();
+				}
+				case "toString" -> {
+					return context.jsonString();
+				}
+			}
+
 			TypeInformation<?> returnType = TypeInformation.fromReturnTypeOf(method);
 			ResolvableType type = ResolvableType.forMethodReturnType(method);
 			boolean isCollectionResult = type.getRawClass() != null && Collection.class.isAssignableFrom(type.getRawClass());

src/main/java/org/springframework/data/web/ProjectingJackson2HttpMessageConverter.java

@@ -48,7 +48,9 @@
  * @author Christoph Strobl
  * @soundtrack Richard Spaven - Ice Is Nice (Spaven's 5ive)
  * @since 1.13
+ * @deprecated since 4.0, in favor of {@link ProjectingJacksonHttpMessageConverter}.
  */
+@Deprecated(since = "4.0", forRemoval = true)
 public class ProjectingJackson2HttpMessageConverter extends MappingJackson2HttpMessageConverter
 		implements BeanClassLoaderAware, BeanFactoryAware {