Add nullability annotations to module/spring-boot-actuator

See gh-46587

Author: mhalbritter

module/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/audit/AuditEvent.java

@@ -24,6 +24,7 @@
 
 import com.fasterxml.jackson.annotation.JsonInclude;
 import com.fasterxml.jackson.annotation.JsonInclude.Include;
+import org.jspecify.annotations.Nullable;
 
 import org.springframework.context.ApplicationEventPublisher;
 import org.springframework.context.ApplicationEventPublisherAware;
@@ -82,7 +83,7 @@ public AuditEvent(String principal, String type, String... data) {
 	 * @param type the event type
 	 * @param data the event data
 	 */
-	public AuditEvent(Instant timestamp, String principal, String type, Map<String, Object> data) {
+	public AuditEvent(Instant timestamp, @Nullable String principal, String type, Map<String, Object> data) {
 		Assert.notNull(timestamp, "'timestamp' must not be null");
 		Assert.notNull(type, "'type' must not be null");
 		this.timestamp = timestamp;

module/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/audit/AuditEventRepository.java

@@ -19,6 +19,8 @@
 import java.time.Instant;
 import java.util.List;
 
+import org.jspecify.annotations.Nullable;
+
 /**
  * Repository for {@link AuditEvent}s.
  *
@@ -44,6 +46,6 @@ public interface AuditEventRepository {
 	 * @return audit events of specified type relating to the principal
 	 * @since 1.4.0
 	 */
-	List<AuditEvent> find(String principal, Instant after, String type);
+	List<AuditEvent> find(@Nullable String principal, @Nullable Instant after, @Nullable String type);
 
 }

module/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/audit/AuditEventsEndpoint.java

@@ -20,6 +20,8 @@
 import java.time.OffsetDateTime;
 import java.util.List;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.boot.actuate.endpoint.OperationResponseBody;
 import org.springframework.boot.actuate.endpoint.annotation.Endpoint;
 import org.springframework.boot.actuate.endpoint.annotation.OptionalParameter;
@@ -49,7 +51,7 @@ public AuditEventsDescriptor events(@OptionalParameter String principal, @Option
 		return new AuditEventsDescriptor(events);
 	}
 
-	private Instant getInstant(OffsetDateTime offsetDateTime) {
+	private @Nullable Instant getInstant(@Nullable OffsetDateTime offsetDateTime) {
 		return (offsetDateTime != null) ? offsetDateTime.toInstant() : null;
 	}
 

module/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/audit/InMemoryAuditEventRepository.java

@@ -20,6 +20,8 @@
 import java.util.LinkedList;
 import java.util.List;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.util.Assert;
 
 /**
@@ -71,7 +73,7 @@ public void add(AuditEvent event) {
 	}
 
 	@Override
-	public List<AuditEvent> find(String principal, Instant after, String type) {
+	public List<AuditEvent> find(@Nullable String principal, @Nullable Instant after, @Nullable String type) {
 		LinkedList<AuditEvent> events = new LinkedList<>();
 		synchronized (this.monitor) {
 			for (int i = 0; i < this.events.length; i++) {
@@ -84,7 +86,8 @@ public List<AuditEvent> find(String principal, Instant after, String type) {
 		return events;
 	}
 
-	private boolean isMatch(String principal, Instant after, String type, AuditEvent event) {
+	private boolean isMatch(@Nullable String principal, @Nullable Instant after, @Nullable String type,
+			AuditEvent event) {
 		boolean match = true;
 		match = match && (principal == null || event.getPrincipal().equals(principal));
 		match = match && (after == null || event.getTimestamp().isAfter(after));

module/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/audit/listener/package-info.java

@@ -17,4 +17,7 @@
 /**
  * Actuator auditing listeners.
  */
+@NullMarked
 package org.springframework.boot.actuate.audit.listener;
+
+import org.jspecify.annotations.NullMarked;

module/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/audit/package-info.java

@@ -17,4 +17,7 @@
 /**
  * Core actuator auditing classes.
  */
+@NullMarked
 package org.springframework.boot.actuate.audit;
+
+import org.jspecify.annotations.NullMarked;

module/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/availability/AvailabilityStateHealthIndicator.java

@@ -21,6 +21,8 @@
 import java.util.Map;
 import java.util.function.Consumer;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.boot.availability.ApplicationAvailability;
 import org.springframework.boot.availability.AvailabilityState;
 import org.springframework.boot.health.contributor.AbstractHealthIndicator;
@@ -92,7 +94,7 @@ protected void doHealthCheck(Health.Builder builder) throws Exception {
 	 * @param applicationAvailability the application availability
 	 * @return the current availability state
 	 */
-	protected AvailabilityState getState(ApplicationAvailability applicationAvailability) {
+	protected @Nullable AvailabilityState getState(ApplicationAvailability applicationAvailability) {
 		return applicationAvailability.getState(this.stateType);
 	}
 
@@ -116,7 +118,7 @@ default void addDefaultStatus(Status status) {
 		 * @param availabilityState the availability state
 		 * @param status the mapped status
 		 */
-		void add(S availabilityState, Status status);
+		void add(@Nullable S availabilityState, Status status);
 
 	}
 

module/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/availability/package-info.java

@@ -17,4 +17,7 @@
 /**
  * Actuator support for application availability concerns.
  */
+@NullMarked
 package org.springframework.boot.actuate.availability;
+
+import org.jspecify.annotations.NullMarked;

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

@@ -19,6 +19,8 @@
 import java.util.HashMap;
 import java.util.Map;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.beans.factory.config.BeanDefinition;
 import org.springframework.beans.factory.config.ConfigurableBeanFactory;
 import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
@@ -63,7 +65,8 @@ public BeansDescriptor beans() {
 		return new BeansDescriptor(contexts);
 	}
 
-	private static ConfigurableApplicationContext getConfigurableParent(ConfigurableApplicationContext context) {
+	private static @Nullable ConfigurableApplicationContext getConfigurableParent(
+			ConfigurableApplicationContext context) {
 		ApplicationContext parent = context.getParent();
 		if (parent instanceof ConfigurableApplicationContext configurableParent) {
 			return configurableParent;
@@ -95,22 +98,22 @@ public static final class ContextBeansDescriptor {
 
 		private final Map<String, BeanDescriptor> beans;
 
-		private final String parentId;
+		private final @Nullable String parentId;
 
-		private ContextBeansDescriptor(Map<String, BeanDescriptor> beans, String parentId) {
+		private ContextBeansDescriptor(Map<String, BeanDescriptor> beans, @Nullable String parentId) {
 			this.beans = beans;
 			this.parentId = parentId;
 		}
 
-		public String getParentId() {
+		public @Nullable String getParentId() {
 			return this.parentId;
 		}
 
 		public Map<String, BeanDescriptor> getBeans() {
 			return this.beans;
 		}
 
-		private static ContextBeansDescriptor describing(ConfigurableApplicationContext context) {
+		private static @Nullable ContextBeansDescriptor describing(@Nullable ConfigurableApplicationContext context) {
 			if (context == null) {
 				return null;
 			}
@@ -150,15 +153,16 @@ public static final class BeanDescriptor {
 
 		private final String[] aliases;
 
-		private final String scope;
+		private final @Nullable String scope;
 
-		private final Class<?> type;
+		private final @Nullable Class<?> type;
 
-		private final String resource;
+		private final @Nullable String resource;
 
 		private final String[] dependencies;
 
-		private BeanDescriptor(String[] aliases, String scope, Class<?> type, String resource, String[] dependencies) {
+		private BeanDescriptor(String[] aliases, @Nullable String scope, @Nullable Class<?> type,
+				@Nullable String resource, String[] dependencies) {
 			this.aliases = aliases;
 			this.scope = (StringUtils.hasText(scope) ? scope : ConfigurableBeanFactory.SCOPE_SINGLETON);
 			this.type = type;
@@ -170,15 +174,15 @@ public String[] getAliases() {
 			return this.aliases;
 		}
 
-		public String getScope() {
+		public @Nullable String getScope() {
 			return this.scope;
 		}
 
-		public Class<?> getType() {
+		public @Nullable Class<?> getType() {
 			return this.type;
 		}
 
-		public String getResource() {
+		public @Nullable String getResource() {
 			return this.resource;
 		}
 

module/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/beans/package-info.java

@@ -17,4 +17,7 @@
 /**
  * Actuator support relating to Spring Beans.
  */
+@NullMarked
 package org.springframework.boot.actuate.beans;
+
+import org.jspecify.annotations.NullMarked;