Do not inspect meta-annotations on Java annotations

This commit introduces a new isInJavaLangAnnotationPackage(Annotation)
method in AnnotationUtils. This method is now used in AnnotationUtils,
AnnotatedElementUtils, and MetaAnnotationUtils to ensure that search
algorithms do no search for meta-annotations on annotations in the
"java.lang.annotation" package.

The following are some empirical results from this change:

- The number of times that the findAnnotation(Class,Class,Set) method in
  AnnotationUtils is recursively invoked while executing
  AnnotationUtilsTests drops from 51 to 29.

- The number of times that the process(AnnotatedElement) method in
  AnnotationUtils.AnnotationCollector is recursively invoked while
  executing AnnotationUtilsTests.getRepeatableFromMethod() drops
  from 16 to 2.

- The number of times that the doProcess() method in
  AnnotatedElementUtils is recursively invoked while executing the
  "getAnnotationAttributes() On MetaCycleAnnotatedClass with missing
  target meta-annotation" test in AnnotatedElementUtilsTests drops
  from 23 to 5.

- The number of times that the findAnnotationDescriptor(Class,Set,Class)
  method in MetaAnnotationUtils is recursively invoked while executing
  the "findAnnotationDescriptor() on MetaCycleAnnotatedClass with
  missing target meta-annotation" test in MetaAnnotationUtilsTests drops
  from 16 to 8.

Issue: SPR-11483

spring-core/src/main/java/org/springframework/core/annotation/AnnotatedElementUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2014 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.
@@ -32,6 +32,7 @@ import org.springframework.util.MultiValueMap;
  *
  * @author Phillip Webb
  * @author Juergen Hoeller
+ * @author Sam Brannen
  * @since 4.0
  */
 public class AnnotatedElementUtils {
@@ -159,7 +160,7 @@ public class AnnotatedElementUtils {
 			for (Annotation annotation : element.getAnnotations()) {
 				if (annotation.annotationType().getName().equals(annotationType) || depth > 0) {
 					T result = processor.process(annotation, depth);
-					if (result != null)  {
+					if (result != null) {
 						return result;
 					}
 					result = doProcess(annotation.annotationType(), annotationType, processor, visited, depth + 1);
@@ -170,10 +171,12 @@ public class AnnotatedElementUtils {
 				}
 			}
 			for (Annotation annotation : element.getAnnotations()) {
-				T result = doProcess(annotation.annotationType(), annotationType, processor, visited, depth);
-				if (result != null) {
-					processor.postProcess(annotation, result);
-					return result;
+				if (!AnnotationUtils.isInJavaLangAnnotationPackage(annotation)) {
+					T result = doProcess(annotation.annotationType(), annotationType, processor, visited, depth);
+					if (result != null) {
+						processor.postProcess(annotation, result);
+						return result;
+					}
 				}
 			}
 		}

spring-core/src/main/java/org/springframework/core/annotation/AnnotationUtils.java

@@ -289,7 +289,7 @@ public abstract class AnnotationUtils {
 			}
 		}
 		for (Annotation ann : clazz.getAnnotations()) {
-			if (visited.add(ann)) {
+			if (!isInJavaLangAnnotationPackage(ann) && visited.add(ann)) {
 				annotation = findAnnotation(ann.annotationType(), annotationType, visited);
 				if (annotation != null) {
 					return annotation;
@@ -422,6 +422,18 @@ public abstract class AnnotationUtils {
 		return (clazz.isAnnotationPresent(annotationType) && !isAnnotationDeclaredLocally(annotationType, clazz));
 	}
 
+	/**
+	 * Determine if the supplied {@link Annotation} is defined in the
+	 * {@code java.lang.annotation} package.
+	 *
+	 * @param annotation the annotation to check; never {@code null}
+	 * @return {@code true} if the annotation is in the {@code java.lang.annotation} package
+	 */
+	public static boolean isInJavaLangAnnotationPackage(Annotation annotation) {
+		Assert.notNull(annotation, "Annotation must not be null");
+		return annotation.annotationType().getName().startsWith("java.lang.annotation");
+	}
+
 	/**
 	 * Retrieve the given annotation's attributes as a Map, preserving all attribute types
 	 * as-is.
@@ -631,7 +643,7 @@ public abstract class AnnotationUtils {
 					else if (ObjectUtils.nullSafeEquals(this.containerAnnotationType, annotation.annotationType())) {
 						result.addAll(Arrays.asList(getValue(annotation)));
 					}
-					else {
+					else if (!isInJavaLangAnnotationPackage(annotation)) {
 						process(annotation.annotationType());
 					}
 				}

spring-core/src/test/java/org/springframework/core/annotation/AnnotatedElementUtilsTests.java

@@ -16,9 +16,12 @@
 
 package org.springframework.core.annotation;
 
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
 import java.lang.annotation.Inherited;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
 
 import org.junit.Test;
 
@@ -32,6 +35,13 @@ import static org.junit.Assert.*;
  */
 public class AnnotatedElementUtilsTests {
 
+	@Test
+	public void getAnnotationAttributesOnMetaCycleAnnotatedClassWithMissingTargetMetaAnnotation() {
+		AnnotationAttributes attributes = AnnotatedElementUtils.getAnnotationAttributes(MetaCycleAnnotatedClass.class,
+			Transactional.class.getName());
+		assertNull("Should not find annotation attributes for @Transactional on MetaCycleAnnotatedClass", attributes);
+	}
+
 	@Test
 	public void getAnnotationAttributesFavorsInheritedAnnotationsOverMoreLocallyDeclaredComposedAnnotations() {
 		AnnotationAttributes attributes = AnnotatedElementUtils.getAnnotationAttributes(
@@ -61,7 +71,34 @@ public class AnnotatedElementUtilsTests {
 
 	// -------------------------------------------------------------------------
 
+	@MetaCycle3
+	@Retention(RetentionPolicy.RUNTIME)
+	@Target(ElementType.ANNOTATION_TYPE)
+	@Documented
+	@interface MetaCycle1 {
+	}
+
+	@MetaCycle1
+	@Retention(RetentionPolicy.RUNTIME)
+	@Target(ElementType.ANNOTATION_TYPE)
+	@Documented
+	@interface MetaCycle2 {
+	}
+
+	@MetaCycle2
+	@Retention(RetentionPolicy.RUNTIME)
+	@Target(ElementType.TYPE)
+	@Documented
+	@interface MetaCycle3 {
+	}
+
+	@MetaCycle3
+	static class MetaCycleAnnotatedClass {
+	}
+
 	@Retention(RetentionPolicy.RUNTIME)
+	@Target(ElementType.TYPE)
+	@Documented
 	@Inherited
 	@interface Transactional {
 
@@ -70,12 +107,16 @@ public class AnnotatedElementUtilsTests {
 
 	@Transactional
 	@Retention(RetentionPolicy.RUNTIME)
+	@Target(ElementType.TYPE)
+	@Documented
 	@Inherited
 	@interface Composed1 {
 	}
 
 	@Transactional(readOnly = true)
 	@Retention(RetentionPolicy.RUNTIME)
+	@Target(ElementType.TYPE)
+	@Documented
 	@interface Composed2 {
 	}
 

spring-core/src/test/java/org/springframework/core/annotation/AnnotationUtilsTests.java

@@ -362,6 +362,13 @@ public class AnnotationUtilsTests {
 		assertNotNull(order);
 	}
 
+	@Test
+	public void findRepeatableAnnotationOnComposedAnnotation() {
+		Repeatable repeatable = findAnnotation(MyRepeatableMeta.class, Repeatable.class);
+		assertNotNull(repeatable);
+		assertEquals(MyRepeatableContainer.class, repeatable.value());
+	}
+
 	@Test
 	public void getRepeatableFromMethod() throws Exception {
 		Method method = InterfaceWithRepeated.class.getMethod("foo");

spring-test/src/main/java/org/springframework/test/context/MetaAnnotationUtils.java

@@ -123,7 +123,7 @@ abstract class MetaAnnotationUtils {
 
 		// Declared on a composed annotation (i.e., as a meta-annotation)?
 		for (Annotation composedAnnotation : clazz.getDeclaredAnnotations()) {
-			if (visited.add(composedAnnotation)) {
+			if (!isInJavaLangAnnotationPackage(composedAnnotation) && visited.add(composedAnnotation)) {
 				AnnotationDescriptor<T> descriptor = findAnnotationDescriptor(composedAnnotation.annotationType(),
 					visited, annotationType);
 				if (descriptor != null) {
@@ -210,7 +210,7 @@ abstract class MetaAnnotationUtils {
 
 		// Declared on a composed annotation (i.e., as a meta-annotation)?
 		for (Annotation composedAnnotation : clazz.getDeclaredAnnotations()) {
-			if (visited.add(composedAnnotation)) {
+			if (!isInJavaLangAnnotationPackage(composedAnnotation) && visited.add(composedAnnotation)) {
 				UntypedAnnotationDescriptor descriptor = findAnnotationDescriptorForTypes(
 					composedAnnotation.annotationType(), visited, annotationTypes);
 				if (descriptor != null) {

spring-test/src/test/java/org/springframework/test/context/MetaAnnotationUtilsTests.java

@@ -17,8 +17,11 @@
 package org.springframework.test.context;
 
 import java.lang.annotation.Annotation;
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
 
 import org.junit.Test;
 import org.springframework.core.annotation.Order;
@@ -393,42 +396,58 @@ public class MetaAnnotationUtilsTests {
 	@Component(value = "meta1")
 	@Order
 	@Retention(RetentionPolicy.RUNTIME)
+	@Target(ElementType.TYPE)
+	@Documented
 	static @interface Meta1 {
 	}
 
 	@Component(value = "meta2")
 	@Transactional
 	@Retention(RetentionPolicy.RUNTIME)
+	@Target(ElementType.TYPE)
+	@Documented
 	static @interface Meta2 {
 	}
 
 	@Meta2
 	@Retention(RetentionPolicy.RUNTIME)
+	@Target(ElementType.TYPE)
+	@Documented
 	@interface MetaMeta {
 	}
 
 	@MetaMeta
 	@Retention(RetentionPolicy.RUNTIME)
+	@Target(ElementType.TYPE)
+	@Documented
 	@interface MetaMetaMeta {
 	}
 
 	@MetaCycle3
 	@Retention(RetentionPolicy.RUNTIME)
+	@Target(ElementType.ANNOTATION_TYPE)
+	@Documented
 	@interface MetaCycle1 {
 	}
 
 	@MetaCycle1
 	@Retention(RetentionPolicy.RUNTIME)
+	@Target(ElementType.ANNOTATION_TYPE)
+	@Documented
 	@interface MetaCycle2 {
 	}
 
 	@MetaCycle2
 	@Retention(RetentionPolicy.RUNTIME)
+	@Target(ElementType.TYPE)
+	@Documented
 	@interface MetaCycle3 {
 	}
 
 	@ContextConfiguration
 	@Retention(RetentionPolicy.RUNTIME)
+	@Target(ElementType.TYPE)
+	@Documented
 	static @interface MetaConfig {
 
 		static class DevConfig {