@bean processing explicitly ignores bridge methods (for method overrides with return type narrowing on JDK 8)

Issue: SPR-11718
(cherry picked from commit 656fc52)

Author: jhoeller

spring-context/src/test/java/org/springframework/context/annotation/BeanMethodPolymorphismTests.java

@@ -23,6 +23,7 @@
 import org.springframework.aop.aspectj.annotation.AnnotationAwareAspectJAutoProxyCreator;
 import org.springframework.aop.interceptor.SimpleTraceInterceptor;
 import org.springframework.aop.support.DefaultPointcutAdvisor;
+import org.springframework.beans.factory.support.RootBeanDefinition;
 
 import static org.hamcrest.CoreMatchers.*;
 import static org.junit.Assert.*;
@@ -55,6 +56,39 @@ public void beanMethodOverriding() {
 		assertTrue(ctx.getDefaultListableBeanFactory().containsSingleton("testBean"));
 	}
 
+	@Test
+	public void beanMethodOverridingOnASM() {
+		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
+		ctx.registerBeanDefinition("config", new RootBeanDefinition(OverridingConfig.class.getName()));
+		ctx.setAllowBeanDefinitionOverriding(false);
+		ctx.refresh();
+		assertFalse(ctx.getDefaultListableBeanFactory().containsSingleton("testBean"));
+		assertEquals("overridden", ctx.getBean("testBean", TestBean.class).toString());
+		assertTrue(ctx.getDefaultListableBeanFactory().containsSingleton("testBean"));
+	}
+
+	@Test
+	public void beanMethodOverridingWithNarrowedReturnType() {
+		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
+		ctx.register(NarrowedOverridingConfig.class);
+		ctx.setAllowBeanDefinitionOverriding(false);
+		ctx.refresh();
+		assertFalse(ctx.getDefaultListableBeanFactory().containsSingleton("testBean"));
+		assertEquals("overridden", ctx.getBean("testBean", TestBean.class).toString());
+		assertTrue(ctx.getDefaultListableBeanFactory().containsSingleton("testBean"));
+	}
+
+	@Test
+	public void beanMethodOverridingWithNarrowedReturnTypeOnASM() {
+		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
+		ctx.registerBeanDefinition("config", new RootBeanDefinition(NarrowedOverridingConfig.class.getName()));
+		ctx.setAllowBeanDefinitionOverriding(false);
+		ctx.refresh();
+		assertFalse(ctx.getDefaultListableBeanFactory().containsSingleton("testBean"));
+		assertEquals("overridden", ctx.getBean("testBean", TestBean.class).toString());
+		assertTrue(ctx.getDefaultListableBeanFactory().containsSingleton("testBean"));
+	}
+
 	@Test
 	public void beanMethodOverloadingWithoutInheritance() {
 		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
@@ -173,6 +207,26 @@ public String toString() {
 	}
 
 
+	static class ExtendedTestBean extends TestBean {
+	}
+
+
+	@Configuration
+	static class NarrowedOverridingConfig extends BaseConfig {
+
+		@Bean @Lazy
+		@Override
+		public ExtendedTestBean testBean() {
+			return new ExtendedTestBean() {
+				@Override
+				public String toString() {
+					return "overridden";
+				}
+			};
+		}
+	}
+
+
 	@Configuration
 	static class ConfigWithOverloading {
 

spring-core/src/main/java/org/springframework/core/type/StandardAnnotationMetadata.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.
@@ -128,7 +128,7 @@ public MultiValueMap<String, Object> getAllAnnotationAttributes(String annotatio
 	public boolean hasAnnotatedMethods(String annotationType) {
 		Method[] methods = getIntrospectedClass().getDeclaredMethods();
 		for (Method method : methods) {
-			if (AnnotatedElementUtils.isAnnotated(method, annotationType)) {
+			if (!method.isBridge() && AnnotatedElementUtils.isAnnotated(method, annotationType)) {
 				return true;
 			}
 		}
@@ -140,7 +140,7 @@ public Set<MethodMetadata> getAnnotatedMethods(String annotationType) {
 		Method[] methods = getIntrospectedClass().getDeclaredMethods();
 		Set<MethodMetadata> annotatedMethods = new LinkedHashSet<MethodMetadata>();
 		for (Method method : methods) {
-			if (AnnotatedElementUtils.isAnnotated(method, annotationType)) {
+			if (!method.isBridge() && AnnotatedElementUtils.isAnnotated(method, annotationType)) {
 				annotatedMethods.add(new StandardMethodMetadata(method, this.nestedAnnotationsAsMap));
 			}
 		}

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

@@ -25,6 +25,7 @@
 
 import org.springframework.asm.AnnotationVisitor;
 import org.springframework.asm.MethodVisitor;
+import org.springframework.asm.Opcodes;
 import org.springframework.asm.Type;
 import org.springframework.core.annotation.AnnotationAttributes;
 import org.springframework.core.type.AnnotationMetadata;
@@ -57,8 +58,7 @@ public class AnnotationMetadataReadingVisitor extends ClassMetadataReadingVisito
 	 * to ensure that the hierarchical ordering of the entries is preserved.
 	 * @see AnnotationReadingVisitorUtils#getMergedAnnotationAttributes(LinkedMultiValueMap, String)
 	 */
-	protected final LinkedMultiValueMap<String, AnnotationAttributes> attributesMap = new LinkedMultiValueMap<String, AnnotationAttributes>(
-		4);
+	protected final LinkedMultiValueMap<String, AnnotationAttributes> attributesMap = new LinkedMultiValueMap<String, AnnotationAttributes>(4);
 
 	protected final Set<MethodMetadata> methodMetadataSet = new LinkedHashSet<MethodMetadata>(4);
 
@@ -70,6 +70,11 @@ public AnnotationMetadataReadingVisitor(ClassLoader classLoader) {
 
 	@Override
 	public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {
+		// Skip bridge methods - we're only interested in original annotation-defining user methods.
+		// On JDK 8, we'd otherwise run into double detection of the same annotated method...
+		if ((access & Opcodes.ACC_BRIDGE) != 0) {
+			return super.visitMethod(access, name, desc, signature, exceptions);
+		}
 		return new MethodMetadataReadingVisitor(name, access, getClassName(), this.classLoader, this.methodMetadataSet);
 	}