Support isolated actuator ObjectMapper

Closes gh-20291

Author: philwebb

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/condition/ConditionsReportEndpoint.java

@@ -27,6 +27,7 @@
 import com.fasterxml.jackson.annotation.JsonInclude.Include;
 import com.fasterxml.jackson.annotation.JsonPropertyOrder;
 
+import org.springframework.boot.actuate.endpoint.OperationResponseBody;
 import org.springframework.boot.actuate.endpoint.annotation.Endpoint;
 import org.springframework.boot.actuate.endpoint.annotation.ReadOperation;
 import org.springframework.boot.autoconfigure.condition.ConditionEvaluationReport;
@@ -81,7 +82,7 @@ private ConfigurableApplicationContext getConfigurableParent(ConfigurableApplica
 	/**
 	 * A description of an application's condition evaluation.
 	 */
-	public static final class ConditionsDescriptor {
+	public static final class ConditionsDescriptor implements OperationResponseBody {
 
 		private final Map<String, ContextConditionsDescriptor> contexts;
 

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/endpoint/jackson/JacksonEndpointAutoConfiguration.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2012-2022 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.actuate.autoconfigure.endpoint.jackson;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+import org.springframework.boot.actuate.endpoint.jackson.EndpointObjectMapper;
+import org.springframework.boot.autoconfigure.AutoConfigureAfter;
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
+import org.springframework.boot.autoconfigure.jackson.JacksonAutoConfiguration;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.http.converter.json.Jackson2ObjectMapperBuilder;
+
+/**
+ * {@link EnableAutoConfiguration Auto-configuration} for Endpoint Jackson support.
+ *
+ * @author Phillip Webb
+ * @since 3.0.0
+ */
+@Configuration(proxyBeanMethods = false)
+@AutoConfigureAfter(JacksonAutoConfiguration.class)
+public class JacksonEndpointAutoConfiguration {
+
+	@Bean
+	@ConditionalOnProperty(name = "management.endpoints.jackson.isolated-object-mapper", matchIfMissing = true)
+	@ConditionalOnClass({ ObjectMapper.class, Jackson2ObjectMapperBuilder.class })
+	public EndpointObjectMapper endpointObjectMapper() {
+		ObjectMapper objectMapper = Jackson2ObjectMapperBuilder.json().build();
+		return () -> objectMapper;
+	}
+
+}