Consider Jackson 2 in HTTP message converter auto-config

See gh-47688

module/spring-boot-http-converter/build.gradle

@@ -33,8 +33,10 @@ dependencies {
 	optional(project(":core:spring-boot-autoconfigure"))
 	optional(project(":module:spring-boot-gson"))
 	optional(project(":module:spring-boot-jackson"))
+	optional(project(":module:spring-boot-jackson2"))
 	optional(project(":module:spring-boot-jsonb"))
 	optional(project(":module:spring-boot-kotlin-serialization"))
+	optional("com.fasterxml.jackson.dataformat:jackson-dataformat-xml")
 	optional("com.google.code.gson:gson")
 	optional("jakarta.json.bind:jakarta.json.bind-api")
 	optional("org.springframework:spring-webmvc")

module/spring-boot-http-converter/src/main/java/org/springframework/boot/http/converter/autoconfigure/GsonHttpMessageConvertersConfiguration.java

@@ -85,6 +85,12 @@ class GsonHttpMessageConvertersConfiguration {
 
 		}
 
+		@SuppressWarnings("removal")
+		@ConditionalOnBean(org.springframework.http.converter.json.MappingJackson2HttpMessageConverter.class)
+		static class Jackson2Available {
+
+		}
+
 		@ConditionalOnProperty(name = HttpMessageConvertersAutoConfiguration.PREFERRED_MAPPER_PROPERTY,
 				havingValue = "jsonb")
 		static class JsonbPreferred {

module/spring-boot-http-converter/src/main/java/org/springframework/boot/http/converter/autoconfigure/HttpMessageConvertersAutoConfiguration.java

@@ -51,14 +51,17 @@ import org.springframework.http.converter.StringHttpMessageConverter;
  * @author Brian Clozel
  * @since 4.0.0
  */
+@SuppressWarnings("removal")
 @AutoConfiguration(afterName = { "org.springframework.boot.jackson.autoconfigure.JacksonAutoConfiguration",
+		"org.springframework.boot.jackson2.autoconfigure.Jackson2AutoConfiguration",
 		"org.springframework.boot.jsonb.autoconfigure.JsonbAutoConfiguration",
 		"org.springframework.boot.gson.autoconfigure.GsonAutoConfiguration",
 		"org.springframework.boot.kotlin.serialization.autoconfigure.KotlinSerializationAutoConfiguration" })
 @ConditionalOnClass(HttpMessageConverter.class)
 @Conditional(NotReactiveWebApplicationCondition.class)
-@Import({ JacksonHttpMessageConvertersConfiguration.class, GsonHttpMessageConvertersConfiguration.class,
-		JsonbHttpMessageConvertersConfiguration.class, KotlinSerializationHttpMessageConvertersConfiguration.class })
+@Import({ JacksonHttpMessageConvertersConfiguration.class, Jackson2HttpMessageConvertersConfiguration.class,
+		GsonHttpMessageConvertersConfiguration.class, JsonbHttpMessageConvertersConfiguration.class,
+		KotlinSerializationHttpMessageConvertersConfiguration.class })
 public final class HttpMessageConvertersAutoConfiguration {
 
 	static final String PREFERRED_MAPPER_PROPERTY = "spring.http.converters.preferred-json-mapper";

module/spring-boot-http-converter/src/main/java/org/springframework/boot/http/converter/autoconfigure/Jackson2HttpMessageConvertersConfiguration.java

@@ -0,0 +1,93 @@
+/*
+ * Copyright 2012-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.boot.http.converter.autoconfigure;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import tools.jackson.dataformat.xml.XmlMapper;
+
+import org.springframework.boot.autoconfigure.condition.AnyNestedCondition;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Conditional;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.http.converter.json.Jackson2ObjectMapperBuilder;
+import org.springframework.http.converter.json.JacksonJsonHttpMessageConverter;
+import org.springframework.http.converter.xml.MappingJackson2XmlHttpMessageConverter;
+
+/**
+ * Configuration for HTTP message converters that use Jackson 2.
+ *
+ * @author Andy Wilkinson
+ * @deprecated since 4.0.0 for removal in 4.2.0 in favor of Jackson 3.
+ */
+@Configuration(proxyBeanMethods = false)
+@Deprecated(since = "4.0.0", forRemoval = true)
+@SuppressWarnings({ "deprecation", "removal" })
+class Jackson2HttpMessageConvertersConfiguration {
+
+	@Configuration(proxyBeanMethods = false)
+	@ConditionalOnClass(ObjectMapper.class)
+	@ConditionalOnBean(ObjectMapper.class)
+	@Conditional(PreferJackson2OrJacksonUnavailableCondition.class)
+	static class MappingJackson2HttpMessageConverterConfiguration {
+
+		@Bean
+		@ConditionalOnMissingBean
+		org.springframework.http.converter.json.MappingJackson2HttpMessageConverter mappingJackson2HttpMessageConverter(
+				ObjectMapper objectMapper) {
+			return new org.springframework.http.converter.json.MappingJackson2HttpMessageConverter(objectMapper);
+		}
+
+	}
+
+	@Configuration(proxyBeanMethods = false)
+	@ConditionalOnClass(XmlMapper.class)
+	@ConditionalOnBean(org.springframework.http.converter.json.Jackson2ObjectMapperBuilder.class)
+	protected static class MappingJackson2XmlHttpMessageConverterConfiguration {
+
+		@Bean
+		@ConditionalOnMissingBean
+		public MappingJackson2XmlHttpMessageConverter mappingJackson2XmlHttpMessageConverter(
+				Jackson2ObjectMapperBuilder builder) {
+			return new MappingJackson2XmlHttpMessageConverter(builder.createXmlMapper(true).build());
+		}
+
+	}
+
+	private static class PreferJackson2OrJacksonUnavailableCondition extends AnyNestedCondition {
+
+		PreferJackson2OrJacksonUnavailableCondition() {
+			super(ConfigurationPhase.REGISTER_BEAN);
+		}
+
+		@ConditionalOnProperty(name = HttpMessageConvertersAutoConfiguration.PREFERRED_MAPPER_PROPERTY,
+				havingValue = "jackson2")
+		static class Jackson2Preferred {
+
+		}
+
+		@ConditionalOnMissingBean(JacksonJsonHttpMessageConverter.class)
+		static class JacksonUnavailable {
+
+		}
+
+	}
+
+}

module/spring-boot-http-converter/src/main/java/org/springframework/boot/http/converter/autoconfigure/JsonbHttpMessageConvertersConfiguration.java

@@ -66,7 +66,10 @@ class JsonbHttpMessageConvertersConfiguration {
 
 		}
 
-		@ConditionalOnMissingBean({ JacksonJsonHttpMessageConverter.class, GsonHttpMessageConverter.class })
+		@SuppressWarnings("removal")
+		@ConditionalOnMissingBean({ JacksonJsonHttpMessageConverter.class,
+				org.springframework.http.converter.json.MappingJackson2HttpMessageConverter.class,
+				GsonHttpMessageConverter.class })
 		static class JacksonAndGsonMissing {
 
 		}

module/spring-boot-http-converter/src/main/resources/META-INF/additional-spring-configuration-metadata.json

@@ -4,7 +4,7 @@
       "name": "spring.http.converters.preferred-json-mapper",
       "type": "java.lang.String",
       "defaultValue": "jackson",
-      "description": "Preferred JSON mapper to use for HTTP message conversion. By default, auto-detected according to the environment. Supported values are 'jackson', 'gson', 'jsonb' and 'kotlin-serialization'. When other json mapping libraries are present, use a custom HttpMessageConverters bean to control the preferred mapper."
+      "description": "Preferred JSON mapper to use for HTTP message conversion. By default, auto-detected according to the environment. Supported values are 'jackson', 'jackson2' (deprecated), 'gson', 'jsonb' and 'kotlin-serialization'. When other json mapping libraries are present, use a custom HttpMessageConverters bean to control the preferred mapper."
     }
   ],
   "hints": [
@@ -17,6 +17,9 @@
         {
           "value": "jackson"
         },
+        {
+          "value": "jackson2"
+        },
         {
           "value": "jsonb"
         }

module/spring-boot-http-converter/src/test/java/org/springframework/boot/http/converter/autoconfigure/HttpMessageConvertersAutoConfigurationTests.java

@@ -19,18 +19,20 @@ package org.springframework.boot.http.converter.autoconfigure;
 import java.nio.charset.StandardCharsets;
 import java.util.List;
 
+import com.fasterxml.jackson.databind.ObjectMapper;
 import com.google.gson.Gson;
 import jakarta.json.bind.Jsonb;
 import jakarta.json.bind.JsonbBuilder;
 import kotlinx.serialization.json.Json;
 import org.junit.jupiter.api.Test;
-import tools.jackson.databind.ObjectMapper;
 import tools.jackson.databind.json.JsonMapper;
 import tools.jackson.dataformat.xml.XmlMapper;
 
 import org.springframework.beans.factory.config.BeanDefinition;
 import org.springframework.boot.autoconfigure.AutoConfigurations;
+import org.springframework.boot.autoconfigure.logging.ConditionEvaluationReportLoggingListener;
 import org.springframework.boot.http.converter.autoconfigure.JacksonHttpMessageConvertersConfiguration.JacksonJsonHttpMessageConverterConfiguration;
+import org.springframework.boot.logging.LogLevel;
 import org.springframework.boot.test.context.FilteredClassLoader;
 import org.springframework.boot.test.context.assertj.AssertableApplicationContext;
 import org.springframework.boot.test.context.runner.ApplicationContextRunner;
@@ -77,7 +79,7 @@ class HttpMessageConvertersAutoConfigurationTests {
 	@Test
 	void jacksonNotAvailable() {
 		this.contextRunner.run((context) -> {
-			assertThat(context).doesNotHaveBean(ObjectMapper.class);
+			assertThat(context).doesNotHaveBean(JsonMapper.class);
 			assertThat(context).doesNotHaveBean(JacksonJsonHttpMessageConverter.class);
 			assertThat(context).doesNotHaveBean(JacksonXmlHttpMessageConverter.class);
 		});
@@ -107,6 +109,34 @@ class HttpMessageConvertersAutoConfigurationTests {
 			.run(assertConverter(JacksonJsonHttpMessageConverter.class, "customJacksonMessageConverter"));
 	}
 
+	@Test
+	@Deprecated(since = "4.0.0", forRemoval = true)
+	@SuppressWarnings("removal")
+	void jackson2DefaultConverter() {
+		this.contextRunner.withUserConfiguration(Jackson2ObjectMapperConfig.class)
+			.withInitializer(ConditionEvaluationReportLoggingListener.forLogLevel(LogLevel.INFO))
+			.run(assertConverter(org.springframework.http.converter.json.MappingJackson2HttpMessageConverter.class,
+					"mappingJackson2HttpMessageConverter"));
+	}
+
+	@Test
+	@Deprecated(since = "4.0.0", forRemoval = true)
+	@SuppressWarnings("removal")
+	void jackson2ConverterWithBuilder() {
+		this.contextRunner.withUserConfiguration(Jackson2ObjectMapperBuilderConfig.class)
+			.run(assertConverter(org.springframework.http.converter.json.MappingJackson2HttpMessageConverter.class,
+					"mappingJackson2HttpMessageConverter"));
+	}
+
+	@Test
+	@Deprecated(since = "4.0.0", forRemoval = true)
+	@SuppressWarnings("removal")
+	void jackson2CustomConverter() {
+		this.contextRunner.withUserConfiguration(Jackson2ObjectMapperConfig.class, Jackson2ConverterConfig.class)
+			.run(assertConverter(org.springframework.http.converter.json.MappingJackson2HttpMessageConverter.class,
+					"customJacksonMessageConverter"));
+	}
+
 	@Test
 	void gsonNotAvailable() {
 		this.contextRunner.run((context) -> {
@@ -244,8 +274,26 @@ class HttpMessageConvertersAutoConfigurationTests {
 	}
 
 	@Test
-	void gsonIsPreferredIfJacksonIsNotAvailable() {
-		allOptionsRunner().withClassLoader(new FilteredClassLoader(ObjectMapper.class.getPackage().getName()))
+	@SuppressWarnings("removal")
+	void jackson2IsPreferredIfJacksonIsNotAvailable() {
+		allOptionsRunner().withClassLoader(new FilteredClassLoader(JsonMapper.class.getPackage().getName()))
+			.withInitializer(ConditionEvaluationReportLoggingListener.forLogLevel(LogLevel.INFO))
+			.run((context) -> {
+				assertConverterBeanExists(context,
+						org.springframework.http.converter.json.MappingJackson2HttpMessageConverter.class,
+						"mappingJackson2HttpMessageConverter");
+				assertConverterBeanRegisteredWithHttpMessageConverters(context,
+						org.springframework.http.converter.json.MappingJackson2HttpMessageConverter.class);
+				assertThat(context).doesNotHaveBean(GsonHttpMessageConverter.class);
+				assertThat(context).doesNotHaveBean(JsonbHttpMessageConverter.class);
+			});
+	}
+
+	@Test
+	void gsonIsPreferredIfJacksonAndJackson2AreNotAvailable() {
+		allOptionsRunner()
+			.withClassLoader(new FilteredClassLoader(JsonMapper.class.getPackage().getName(),
+					ObjectMapper.class.getPackage().getName()))
 			.run((context) -> {
 				assertConverterBeanExists(context, GsonHttpMessageConverter.class, "gsonHttpMessageConverter");
 				assertConverterBeanRegisteredWithHttpMessageConverters(context, GsonHttpMessageConverter.class);
@@ -256,8 +304,8 @@ class HttpMessageConvertersAutoConfigurationTests {
 	@Test
 	void jsonbIsPreferredIfJacksonAndGsonAreNotAvailable() {
 		allOptionsRunner()
-			.withClassLoader(new FilteredClassLoader(ObjectMapper.class.getPackage().getName(),
-					Gson.class.getPackage().getName()))
+			.withClassLoader(new FilteredClassLoader(JsonMapper.class.getPackage().getName(),
+					ObjectMapper.class.getPackage().getName(), Gson.class.getPackage().getName()))
 			.run(assertConverter(JsonbHttpMessageConverter.class, "jsonbHttpMessageConverter"));
 	}
 
@@ -303,6 +351,7 @@ class HttpMessageConvertersAutoConfigurationTests {
 	private ApplicationContextRunner allOptionsRunner() {
 		return this.contextRunner.withBean(Gson.class)
 			.withBean(JsonMapper.class)
+			.withBean(ObjectMapper.class, ObjectMapper::new)
 			.withBean(Jsonb.class, JsonbBuilder::create)
 			.withBean(Json.class, () -> Json.Default);
 	}
@@ -403,6 +452,48 @@ class HttpMessageConvertersAutoConfigurationTests {
 
 	}
 
+	@Configuration(proxyBeanMethods = false)
+	static class Jackson2ObjectMapperConfig {
+
+		@Bean
+		ObjectMapper objectMapper() {
+			return new ObjectMapper();
+		}
+
+	}
+
+	@Configuration(proxyBeanMethods = false)
+	@Deprecated(since = "4.0.0", forRemoval = true)
+	@SuppressWarnings("removal")
+	static class Jackson2ObjectMapperBuilderConfig {
+
+		@Bean
+		ObjectMapper objectMapper() {
+			return new ObjectMapper();
+		}
+
+		@Bean
+		org.springframework.http.converter.json.Jackson2ObjectMapperBuilder builder() {
+			return new org.springframework.http.converter.json.Jackson2ObjectMapperBuilder();
+		}
+
+	}
+
+	@Deprecated(since = "4.0.0", forRemoval = true)
+	@Configuration(proxyBeanMethods = false)
+	@SuppressWarnings("removal")
+	static class Jackson2ConverterConfig {
+
+		@Bean
+		org.springframework.http.converter.json.MappingJackson2HttpMessageConverter customJacksonMessageConverter(
+				ObjectMapper objectMapper) {
+			org.springframework.http.converter.json.MappingJackson2HttpMessageConverter converter = new org.springframework.http.converter.json.MappingJackson2HttpMessageConverter();
+			converter.setObjectMapper(objectMapper);
+			return converter;
+		}
+
+	}
+
 	@Configuration(proxyBeanMethods = false)
 	static class GsonConverterConfig {