Migrate endpoints to return OperationResponseBody types

Update types returned from endpoints to implement the
`OperationResponseBody` interface. This ensures that they will be
serialized using the isolated actuator `ObjectMapper`.

See gh-20291

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;
 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 @@ public class ConditionsReportEndpoint {
 	/**
 	 * 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/src/main/java/org/springframework/boot/actuate/audit/AuditEventsEndpoint.java

@@ -20,6 +20,7 @@ import java.time.Instant;
 import java.time.OffsetDateTime;
 import java.util.List;
 
+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.lang.Nullable;
@@ -55,7 +56,7 @@ public class AuditEventsEndpoint {
 	/**
 	 * Description of an application's {@link AuditEvent audit events}.
 	 */
-	public static final class AuditEventsDescriptor {
+	public static final class AuditEventsDescriptor implements OperationResponseBody {
 
 		private final List<AuditEvent> events;
 

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/beans/BeansEndpoint.java

@@ -22,6 +22,7 @@ import java.util.Map;
 import org.springframework.beans.factory.config.BeanDefinition;
 import org.springframework.beans.factory.config.ConfigurableBeanFactory;
 import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
+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.context.ApplicationContext;
@@ -73,7 +74,7 @@ public class BeansEndpoint {
 	/**
 	 * Description of an application's beans.
 	 */
-	public static final class BeansDescriptor {
+	public static final class BeansDescriptor implements OperationResponseBody {
 
 		private final Map<String, ContextBeansDescriptor> contexts;
 

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/cache/CachesEndpoint.java

@@ -22,6 +22,7 @@ import java.util.Map;
 import java.util.Objects;
 import java.util.function.Predicate;
 
+import org.springframework.boot.actuate.endpoint.OperationResponseBody;
 import org.springframework.boot.actuate.endpoint.annotation.DeleteOperation;
 import org.springframework.boot.actuate.endpoint.annotation.Endpoint;
 import org.springframework.boot.actuate.endpoint.annotation.ReadOperation;
@@ -148,7 +149,7 @@ public class CachesEndpoint {
 	/**
 	 * Description of the caches.
 	 */
-	public static final class CachesDescriptor {
+	public static final class CachesDescriptor implements OperationResponseBody {
 
 		private final Map<String, CacheManagerDescriptor> cacheManagers;
 
@@ -182,7 +183,7 @@ public class CachesEndpoint {
 	/**
 	 * Description of a {@link Cache}.
 	 */
-	public static class CacheDescriptor {
+	public static class CacheDescriptor implements OperationResponseBody {
 
 		private final String target;
 

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/context/ShutdownEndpoint.java

@@ -17,6 +17,7 @@
 package org.springframework.boot.actuate.context;
 
 import org.springframework.beans.BeansException;
+import org.springframework.boot.actuate.endpoint.OperationResponseBody;
 import org.springframework.boot.actuate.endpoint.annotation.Endpoint;
 import org.springframework.boot.actuate.endpoint.annotation.WriteOperation;
 import org.springframework.context.ApplicationContext;
@@ -71,7 +72,7 @@ public class ShutdownEndpoint implements ApplicationContextAware {
 	/**
 	 * Description of the shutdown.
 	 */
-	public static class ShutdownDescriptor {
+	public static class ShutdownDescriptor implements OperationResponseBody {
 
 		private static final ShutdownDescriptor DEFAULT = new ShutdownDescriptor("Shutting down, bye...");
 

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/context/properties/ConfigurationPropertiesReportEndpoint.java

@@ -54,6 +54,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
 import org.springframework.beans.BeansException;
+import org.springframework.boot.actuate.endpoint.OperationResponseBody;
 import org.springframework.boot.actuate.endpoint.SanitizableData;
 import org.springframework.boot.actuate.endpoint.Sanitizer;
 import org.springframework.boot.actuate.endpoint.SanitizingFunction;
@@ -564,7 +565,7 @@ public class ConfigurationPropertiesReportEndpoint implements ApplicationContext
 	 * Description of an application's
 	 * {@link ConfigurationProperties @ConfigurationProperties} beans.
 	 */
-	public static final class ConfigurationPropertiesDescriptor {
+	public static final class ConfigurationPropertiesDescriptor implements OperationResponseBody {
 
 		private final Map<String, ContextConfigurationPropertiesDescriptor> contexts;
 

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/web/jersey/JerseyEndpointResourceFactory.java

@@ -43,6 +43,7 @@ import reactor.core.publisher.Mono;
 import org.springframework.boot.actuate.endpoint.InvalidEndpointRequestException;
 import org.springframework.boot.actuate.endpoint.InvocationContext;
 import org.springframework.boot.actuate.endpoint.OperationArgumentResolver;
+import org.springframework.boot.actuate.endpoint.OperationResponseBody;
 import org.springframework.boot.actuate.endpoint.ProducibleOperationArgumentResolver;
 import org.springframework.boot.actuate.endpoint.SecurityContext;
 import org.springframework.boot.actuate.endpoint.web.EndpointLinksResolver;
@@ -323,7 +324,8 @@ public class JerseyEndpointResourceFactory {
 		public Response apply(ContainerRequestContext request) {
 			Map<String, Link> links = this.linksResolver
 					.resolveLinks(request.getUriInfo().getAbsolutePath().toString());
-			return Response.ok(Collections.singletonMap("_links", links)).build();
+			Map<String, Map<String, Link>> entity = OperationResponseBody.of(Collections.singletonMap("_links", links));
+			return Response.ok(entity).build();
 		}
 
 	}

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/web/reactive/WebFluxEndpointHandlerMapping.java

@@ -26,6 +26,7 @@ import org.springframework.aot.hint.RuntimeHintsRegistrar;
 import org.springframework.aot.hint.annotation.Reflective;
 import org.springframework.aot.hint.annotation.ReflectiveRuntimeHintsRegistrar;
 import org.springframework.beans.factory.InitializingBean;
+import org.springframework.boot.actuate.endpoint.OperationResponseBody;
 import org.springframework.boot.actuate.endpoint.web.EndpointLinksResolver;
 import org.springframework.boot.actuate.endpoint.web.EndpointMapping;
 import org.springframework.boot.actuate.endpoint.web.EndpointMediaTypes;
@@ -87,8 +88,8 @@ public class WebFluxEndpointHandlerMapping extends AbstractWebFluxEndpointHandle
 		public Map<String, Map<String, Link>> links(ServerWebExchange exchange) {
 			String requestUri = UriComponentsBuilder.fromUri(exchange.getRequest().getURI()).replaceQuery(null)
 					.toUriString();
-			return Collections.singletonMap("_links",
+			Map<String, Link> links = WebFluxEndpointHandlerMapping.this.linksResolver.resolveLinks(requestUri);
-					WebFluxEndpointHandlerMapping.this.linksResolver.resolveLinks(requestUri));
+			return OperationResponseBody.of(Collections.singletonMap("_links", links));
 		}
 
 		@Override

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/web/servlet/WebMvcEndpointHandlerMapping.java

@@ -28,6 +28,7 @@ import org.springframework.aot.hint.RuntimeHints;
 import org.springframework.aot.hint.RuntimeHintsRegistrar;
 import org.springframework.aot.hint.annotation.Reflective;
 import org.springframework.aot.hint.annotation.ReflectiveRuntimeHintsRegistrar;
+import org.springframework.boot.actuate.endpoint.OperationResponseBody;
 import org.springframework.boot.actuate.endpoint.web.EndpointLinksResolver;
 import org.springframework.boot.actuate.endpoint.web.EndpointMapping;
 import org.springframework.boot.actuate.endpoint.web.EndpointMediaTypes;
@@ -84,8 +85,9 @@ public class WebMvcEndpointHandlerMapping extends AbstractWebMvcEndpointHandlerM
 		@ResponseBody
 		@Reflective
 		public Map<String, Map<String, Link>> links(HttpServletRequest request, HttpServletResponse response) {
-			return Collections.singletonMap("_links",
+			Map<String, Link> links = WebMvcEndpointHandlerMapping.this.linksResolver
-					WebMvcEndpointHandlerMapping.this.linksResolver.resolveLinks(request.getRequestURL().toString()));
+					.resolveLinks(request.getRequestURL().toString());
+			return OperationResponseBody.of(Collections.singletonMap("_links", links));
 		}
 
 		@Override

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/env/EnvironmentEndpoint.java

@@ -27,6 +27,7 @@ import java.util.stream.Stream;
 
 import com.fasterxml.jackson.annotation.JsonInclude;
 
+import org.springframework.boot.actuate.endpoint.OperationResponseBody;
 import org.springframework.boot.actuate.endpoint.SanitizableData;
 import org.springframework.boot.actuate.endpoint.Sanitizer;
 import org.springframework.boot.actuate.endpoint.SanitizingFunction;
@@ -203,7 +204,7 @@ public class EnvironmentEndpoint {
 	/**
 	 * Description of an {@link Environment}.
 	 */
-	public static final class EnvironmentDescriptor {
+	public static final class EnvironmentDescriptor implements OperationResponseBody {
 
 		private final List<String> activeProfiles;
 

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/flyway/FlywayEndpoint.java

@@ -28,6 +28,7 @@ import org.flywaydb.core.Flyway;
 import org.flywaydb.core.api.MigrationInfo;
 import org.flywaydb.core.api.MigrationState;
 
+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.context.ApplicationContext;
@@ -69,7 +70,7 @@ public class FlywayEndpoint {
 	/**
 	 * Description of an application's {@link Flyway} beans.
 	 */
-	public static final class FlywayBeansDescriptor {
+	public static final class FlywayBeansDescriptor implements OperationResponseBody {
 
 		private final Map<String, ContextFlywayBeansDescriptor> contexts;
 

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/health/HealthComponent.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2021 the original author or authors.
+ * 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.
@@ -18,6 +18,8 @@ package org.springframework.boot.actuate.health;
 
 import com.fasterxml.jackson.annotation.JsonUnwrapped;
 
+import org.springframework.boot.actuate.endpoint.OperationResponseBody;
+
 /**
  * A component that contributes data to results returned from the {@link HealthEndpoint}.
  *
@@ -26,7 +28,7 @@ import com.fasterxml.jackson.annotation.JsonUnwrapped;
  * @see Health
  * @see CompositeHealth
  */
-public abstract class HealthComponent {
+public abstract class HealthComponent implements OperationResponseBody {
 
 	HealthComponent() {
 	}

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/info/InfoEndpoint.java

@@ -19,6 +19,7 @@ package org.springframework.boot.actuate.info;
 import java.util.List;
 import java.util.Map;
 
+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.util.Assert;
@@ -51,7 +52,7 @@ public class InfoEndpoint {
 		for (InfoContributor contributor : this.infoContributors) {
 			contributor.contribute(builder);
 		}
-		return builder.build().getDetails();
+		return OperationResponseBody.of(builder.build().getDetails());
 	}
 
 }

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/integration/IntegrationGraphEndpoint.java

@@ -22,6 +22,7 @@ import java.util.Map;
 import org.springframework.aot.hint.BindingReflectionHintsRegistrar;
 import org.springframework.aot.hint.RuntimeHints;
 import org.springframework.aot.hint.RuntimeHintsRegistrar;
+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.actuate.endpoint.annotation.WriteOperation;
@@ -99,7 +100,7 @@ public class IntegrationGraphEndpoint {
 	/**
 	 * Description of a {@link Graph}.
 	 */
-	public static class GraphDescriptor {
+	public static class GraphDescriptor implements OperationResponseBody {
 
 		private final Map<String, Object> contentDescriptor;
 

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/liquibase/LiquibaseEndpoint.java

@@ -32,6 +32,7 @@ import liquibase.database.DatabaseFactory;
 import liquibase.database.jvm.JdbcConnection;
 import liquibase.integration.spring.SpringLiquibase;
 
+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.context.ApplicationContext;
@@ -106,7 +107,7 @@ public class LiquibaseEndpoint {
 	/**
 	 * Description of an application's {@link SpringLiquibase} beans.
 	 */
-	public static final class LiquibaseBeansDescriptor {
+	public static final class LiquibaseBeansDescriptor implements OperationResponseBody {
 
 		private final Map<String, ContextLiquibaseBeansDescriptor> contexts;
 

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/logging/LoggersEndpoint.java

@@ -25,6 +25,7 @@ import java.util.Set;
 import java.util.TreeSet;
 
 import org.springframework.aot.hint.annotation.RegisterReflectionForBinding;
+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.actuate.endpoint.annotation.Selector;
@@ -121,7 +122,7 @@ public class LoggersEndpoint {
 	/**
 	 * Description of loggers.
 	 */
-	public static class LoggersDescriptor {
+	public static class LoggersDescriptor implements OperationResponseBody {
 
 		/**
 		 * Empty description.
@@ -158,7 +159,7 @@ public class LoggersEndpoint {
 	/**
 	 * Description of levels configured for a given logger.
 	 */
-	public static class LoggerLevelsDescriptor {
+	public static class LoggerLevelsDescriptor implements OperationResponseBody {
 
 		private String configuredLevel;
 

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/management/ThreadDumpEndpoint.java

@@ -22,6 +22,7 @@ import java.util.Arrays;
 import java.util.List;
 import java.util.function.Function;
 
+import org.springframework.boot.actuate.endpoint.OperationResponseBody;
 import org.springframework.boot.actuate.endpoint.annotation.Endpoint;
 import org.springframework.boot.actuate.endpoint.annotation.ReadOperation;
 
@@ -54,7 +55,7 @@ public class ThreadDumpEndpoint {
 	/**
 	 * Description of a thread dump.
 	 */
-	public static final class ThreadDumpDescriptor {
+	public static final class ThreadDumpDescriptor implements OperationResponseBody {
 
 		private final List<ThreadInfo> threads;
 

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/MetricsEndpoint.java

@@ -34,6 +34,7 @@ import io.micrometer.core.instrument.Tag;
 import io.micrometer.core.instrument.composite.CompositeMeterRegistry;
 
 import org.springframework.boot.actuate.endpoint.InvalidEndpointRequestException;
+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.actuate.endpoint.annotation.Selector;
@@ -159,7 +160,7 @@ public class MetricsEndpoint {
 	/**
 	 * Description of metric names.
 	 */
-	public static final class MetricNamesDescriptor {
+	public static final class MetricNamesDescriptor implements OperationResponseBody {
 
 		private final Set<String> names;
 
@@ -176,7 +177,7 @@ public class MetricsEndpoint {
 	/**
 	 * Description of a metric.
 	 */
-	public static final class MetricDescriptor {
+	public static final class MetricDescriptor implements OperationResponseBody {
 
 		private final String name;
 

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/quartz/QuartzEndpoint.java

@@ -47,6 +47,7 @@ import org.quartz.Trigger.TriggerState;
 import org.quartz.TriggerKey;
 import org.quartz.impl.matchers.GroupMatcher;
 
+import org.springframework.boot.actuate.endpoint.OperationResponseBody;
 import org.springframework.boot.actuate.endpoint.SanitizableData;
 import org.springframework.boot.actuate.endpoint.Sanitizer;
 import org.springframework.boot.actuate.endpoint.SanitizingFunction;
@@ -236,8 +237,9 @@ public class QuartzEndpoint {
 			return null;
 		}
 		TriggerState triggerState = this.scheduler.getTriggerState(triggerKey);
-		return TriggerDescriptor.of(trigger).buildDetails(triggerState,
+		TriggerDescriptor triggerDescriptor = TriggerDescriptor.of(trigger);
-				sanitizeJobDataMap(trigger.getJobDataMap(), showUnsanitized));
+		Map<String, Object> jobDataMap = sanitizeJobDataMap(trigger.getJobDataMap(), showUnsanitized);
+		return OperationResponseBody.of(triggerDescriptor.buildDetails(triggerState, jobDataMap));
 	}
 
 	private static Duration getIntervalDuration(long amount, IntervalUnit unit) {
@@ -279,7 +281,7 @@ public class QuartzEndpoint {
 	/**
 	 * Description of available job and trigger group names.
 	 */
-	public static final class QuartzDescriptor {
+	public static final class QuartzDescriptor implements OperationResponseBody {
 
 		private final GroupNamesDescriptor jobs;
 
@@ -320,7 +322,7 @@ public class QuartzEndpoint {
 	/**
 	 * Description of each group identified by name.
 	 */
-	public static class QuartzGroupsDescriptor {
+	public static class QuartzGroupsDescriptor implements OperationResponseBody {
 
 		private final Map<String, Object> groups;
 
@@ -337,7 +339,7 @@ public class QuartzEndpoint {
 	/**
 	 * Description of the {@link JobDetail jobs} in a given group.
 	 */
-	public static final class QuartzJobGroupSummaryDescriptor {
+	public static final class QuartzJobGroupSummaryDescriptor implements OperationResponseBody {
 
 		private final String group;
 
@@ -382,7 +384,7 @@ public class QuartzEndpoint {
 	/**
 	 * Description of a {@link Job Quartz Job}.
 	 */
-	public static final class QuartzJobDetailsDescriptor {
+	public static final class QuartzJobDetailsDescriptor implements OperationResponseBody {
 
 		private final String group;
 
@@ -449,7 +451,7 @@ public class QuartzEndpoint {
 	/**
 	 * Description of the {@link Trigger triggers} in a given group.
 	 */
-	public static final class QuartzTriggerGroupSummaryDescriptor {
+	public static final class QuartzTriggerGroupSummaryDescriptor implements OperationResponseBody {
 
 		private final String group;
 

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/scheduling/ScheduledTasksEndpoint.java

@@ -29,6 +29,7 @@ import java.util.stream.Collectors;
 import org.springframework.aot.hint.BindingReflectionHintsRegistrar;
 import org.springframework.aot.hint.RuntimeHints;
 import org.springframework.aot.hint.RuntimeHintsRegistrar;
+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.actuate.scheduling.ScheduledTasksEndpoint.ScheduledTasksEndpointRuntimeHints;
@@ -75,7 +76,7 @@ public class ScheduledTasksEndpoint {
 	/**
 	 * Description of an application's scheduled {@link Task Tasks}.
 	 */
-	public static final class ScheduledTasksDescriptor {
+	public static final class ScheduledTasksDescriptor implements OperationResponseBody {
 
 		private final List<TaskDescriptor> cron;
 

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/session/SessionsEndpoint.java

@@ -21,6 +21,7 @@ import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
+import org.springframework.boot.actuate.endpoint.OperationResponseBody;
 import org.springframework.boot.actuate.endpoint.annotation.DeleteOperation;
 import org.springframework.boot.actuate.endpoint.annotation.Endpoint;
 import org.springframework.boot.actuate.endpoint.annotation.ReadOperation;
@@ -70,7 +71,7 @@ public class SessionsEndpoint {
 	/**
 	 * Description of user's {@link Session sessions}.
 	 */
-	public static final class SessionsDescriptor {
+	public static final class SessionsDescriptor implements OperationResponseBody {
 
 		private final List<SessionDescriptor> sessions;
 
@@ -87,7 +88,7 @@ public class SessionsEndpoint {
 	/**
 	 * Description of user's {@link Session session}.
 	 */
-	public static final class SessionDescriptor {
+	public static final class SessionDescriptor implements OperationResponseBody {
 
 		private final String id;
 

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/startup/StartupEndpoint.java

@@ -21,6 +21,7 @@ import org.springframework.aot.hint.RuntimeHints;
 import org.springframework.aot.hint.RuntimeHintsRegistrar;
 import org.springframework.aot.hint.TypeReference;
 import org.springframework.boot.SpringBootVersion;
+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.actuate.endpoint.annotation.WriteOperation;
@@ -68,7 +69,7 @@ public class StartupEndpoint {
 	/**
 	 * Description of an application startup.
 	 */
-	public static final class StartupDescriptor {
+	public static final class StartupDescriptor implements OperationResponseBody {
 
 		private final String springBootVersion;
 

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/web/exchanges/HttpExchangesEndpoint.java

@@ -18,6 +18,7 @@ package org.springframework.boot.actuate.web.exchanges;
 
 import java.util.List;
 
+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.util.Assert;
@@ -51,7 +52,7 @@ public class HttpExchangesEndpoint {
 	/**
 	 * Description of an application's {@link HttpExchange} entries.
 	 */
-	public static final class HttpExchangesDescriptor {
+	public static final class HttpExchangesDescriptor implements OperationResponseBody {
 
 		private final List<HttpExchange> exchanges;
 

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/web/mappings/MappingsEndpoint.java

@@ -20,6 +20,7 @@ import java.util.Collection;
 import java.util.HashMap;
 import java.util.Map;
 
+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.context.ApplicationContext;
@@ -64,7 +65,7 @@ public class MappingsEndpoint {
 	/**
 	 * Description of an application's request mappings.
 	 */
-	public static final class ApplicationMappingsDescriptor {
+	public static final class ApplicationMappingsDescriptor implements OperationResponseBody {
 
 		private final Map<String, ContextMappingsDescriptor> contextMappings;
 

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/integration/IntegrationGraphEndpointTests.java

@@ -68,19 +68,19 @@ class IntegrationGraphEndpointTests {
 
 	@Test
 	void readOperationShouldReturnGraph() {
-		Graph mockedGraph = mock(Graph.class);
+		Graph graph = mock(Graph.class);
 		Map<String, Object> contentDescriptor = new LinkedHashMap<>();
 		Collection<IntegrationNode> nodes = new ArrayList<>();
 		Collection<LinkNode> links = new ArrayList<>();
-		given(mockedGraph.getContentDescriptor()).willReturn(contentDescriptor);
+		given(graph.getContentDescriptor()).willReturn(contentDescriptor);
-		given(mockedGraph.getNodes()).willReturn(nodes);
+		given(graph.getNodes()).willReturn(nodes);
-		given(mockedGraph.getLinks()).willReturn(links);
+		given(graph.getLinks()).willReturn(links);
-		given(this.server.getGraph()).willReturn(mockedGraph);
+		given(this.server.getGraph()).willReturn(graph);
-		GraphDescriptor graph = this.endpoint.graph();
+		GraphDescriptor descriptor = this.endpoint.graph();
 		then(this.server).should().getGraph();
-		assertThat(graph.getContentDescriptor()).isSameAs(contentDescriptor);
+		assertThat(descriptor.getContentDescriptor()).isSameAs(contentDescriptor);
-		assertThat(graph.getNodes()).isSameAs(nodes);
+		assertThat(descriptor.getNodes()).isSameAs(nodes);
-		assertThat(graph.getLinks()).isSameAs(links);
+		assertThat(descriptor.getLinks()).isSameAs(links);
 	}
 
 	@Test