Avoid synthesizable check for common annotation types

This revision immediately returns false from isSynthesizable for java.lang.annotation types.

Issue: SPR-16933

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

@@ -1584,7 +1584,7 @@ public abstract class AnnotationUtils {
 	 * @see #synthesizeAnnotation(Annotation, AnnotatedElement)
 	 */
 	public static <A extends Annotation> A synthesizeAnnotation(Class<A> annotationType) {
-		return synthesizeAnnotation(Collections.<String, Object> emptyMap(), annotationType, null);
+		return synthesizeAnnotation(Collections.emptyMap(), annotationType, null);
 	}
 
 	/**
@@ -1603,9 +1603,7 @@ public abstract class AnnotationUtils {
 	 * @see #synthesizeAnnotation(Annotation, AnnotatedElement)
 	 * @see #synthesizeAnnotation(Map, Class, AnnotatedElement)
 	 */
-	static Annotation[] synthesizeAnnotationArray(
-			Annotation[] annotations, @Nullable Object annotatedElement) {
-
+	static Annotation[] synthesizeAnnotationArray(Annotation[] annotations, @Nullable Object annotatedElement) {
 		Annotation[] synthesized = (Annotation[]) Array.newInstance(
 				annotations.getClass().getComponentType(), annotations.length);
 		for (int i = 0; i < annotations.length; i++) {
@@ -1633,7 +1631,9 @@ public abstract class AnnotationUtils {
 	 */
 	@SuppressWarnings("unchecked")
 	@Nullable
-	static <A extends Annotation> A[] synthesizeAnnotationArray(@Nullable Map<String, Object>[] maps, Class<A> annotationType) {
+	static <A extends Annotation> A[] synthesizeAnnotationArray(
+			@Nullable Map<String, Object>[] maps, Class<A> annotationType) {
+
 		if (maps == null) {
 			return null;
 		}
@@ -1715,6 +1715,10 @@ public abstract class AnnotationUtils {
 	 */
 	@SuppressWarnings("unchecked")
 	private static boolean isSynthesizable(Class<? extends Annotation> annotationType) {
+		if (isInJavaLangAnnotationPackage(annotationType)) {
+			return false;
+		}
+
 		Boolean synthesizable = synthesizableCache.get(annotationType);
 		if (synthesizable != null) {
 			return synthesizable;

spring-core/src/main/java/org/springframework/core/type/classreading/AnnotationAttributesReadingVisitor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -64,7 +64,7 @@ final class AnnotationAttributesReadingVisitor extends RecursiveAnnotationAttrib
 	public void visitEnd() {
 		super.visitEnd();
 
-		Class<?> annotationClass = this.attributes.annotationType();
+		Class<? extends Annotation> annotationClass = this.attributes.annotationType();
 		if (annotationClass != null) {
 			List<AnnotationAttributes> attributeList = this.attributesMap.get(this.annotationType);
 			if (attributeList == null) {
@@ -73,20 +73,22 @@ final class AnnotationAttributesReadingVisitor extends RecursiveAnnotationAttrib
 			else {
 				attributeList.add(0, this.attributes);
 			}
-			Set<Annotation> visited = new LinkedHashSet<>();
-			Annotation[] metaAnnotations = AnnotationUtils.getAnnotations(annotationClass);
-			if (!ObjectUtils.isEmpty(metaAnnotations)) {
-				for (Annotation metaAnnotation : metaAnnotations) {
-					if (!AnnotationUtils.isInJavaLangAnnotationPackage(metaAnnotation)) {
-						recursivelyCollectMetaAnnotations(visited, metaAnnotation);
+			if (!AnnotationUtils.isInJavaLangAnnotationPackage(annotationClass.getName())) {
+				Set<Annotation> visited = new LinkedHashSet<>();
+				Annotation[] metaAnnotations = AnnotationUtils.getAnnotations(annotationClass);
+				if (!ObjectUtils.isEmpty(metaAnnotations)) {
+					for (Annotation metaAnnotation : metaAnnotations) {
+						if (!AnnotationUtils.isInJavaLangAnnotationPackage(metaAnnotation)) {
+							recursivelyCollectMetaAnnotations(visited, metaAnnotation);
+						}
 					}
 				}
+				Set<String> metaAnnotationTypeNames = new LinkedHashSet<>(visited.size());
+				for (Annotation ann : visited) {
+					metaAnnotationTypeNames.add(ann.annotationType().getName());
+				}
+				this.metaAnnotationMap.put(annotationClass.getName(), metaAnnotationTypeNames);
 			}
-			Set<String> metaAnnotationTypeNames = new LinkedHashSet<>(visited.size());
-			for (Annotation ann : visited) {
-				metaAnnotationTypeNames.add(ann.annotationType().getName());
-			}
-			this.metaAnnotationMap.put(annotationClass.getName(), metaAnnotationTypeNames);
 		}
 	}