Restore ability to return original method for proxy-derived method

Closes gh-32365

spring-aop/src/main/java/org/springframework/aop/support/AopUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -186,10 +186,10 @@ public abstract class AopUtils {
 	 * this method resolves bridge methods in order to retrieve attributes from
 	 * the <i>original</i> method definition.
 	 * @param method the method to be invoked, which may come from an interface
-	 * @param targetClass the target class for the current invocation.
-	 * May be {@code null} or may not even implement the method.
+	 * @param targetClass the target class for the current invocation
+	 * (can be {@code null} or may not even implement the method)
 	 * @return the specific target method, or the original method if the
-	 * {@code targetClass} doesn't implement it or is {@code null}
+	 * {@code targetClass} does not implement it
 	 * @see org.springframework.util.ClassUtils#getMostSpecificMethod
 	 */
 	public static Method getMostSpecificMethod(Method method, @Nullable Class<?> targetClass) {

spring-aop/src/test/java/org/springframework/aop/support/AopUtilsTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -17,29 +17,35 @@
 package org.springframework.aop.support;
 
 import java.lang.reflect.Method;
+import java.util.List;
 
 import org.junit.jupiter.api.Test;
 
 import org.springframework.aop.ClassFilter;
 import org.springframework.aop.MethodMatcher;
 import org.springframework.aop.Pointcut;
+import org.springframework.aop.framework.ProxyFactory;
 import org.springframework.aop.interceptor.ExposeInvocationInterceptor;
 import org.springframework.aop.target.EmptyTargetSource;
 import org.springframework.aop.testfixture.interceptor.NopInterceptor;
 import org.springframework.beans.testfixture.beans.TestBean;
+import org.springframework.core.ResolvableType;
 import org.springframework.core.testfixture.io.SerializationTestUtils;
 import org.springframework.lang.Nullable;
+import org.springframework.util.ReflectionUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
 /**
  * @author Rod Johnson
  * @author Chris Beams
+ * @author Sebastien Deleuze
+ * @author Juergen Hoeller
  */
-public class AopUtilsTests {
+class AopUtilsTests {
 
 	@Test
-	public void testPointcutCanNeverApply() {
+	void testPointcutCanNeverApply() {
 		class TestPointcut extends StaticMethodMatcherPointcut {
 			@Override
 			public boolean matches(Method method, @Nullable Class<?> clazzy) {
@@ -52,13 +58,13 @@ public class AopUtilsTests {
 	}
 
 	@Test
-	public void testPointcutAlwaysApplies() {
+	void testPointcutAlwaysApplies() {
 		assertThat(AopUtils.canApply(new DefaultPointcutAdvisor(new NopInterceptor()), Object.class)).isTrue();
 		assertThat(AopUtils.canApply(new DefaultPointcutAdvisor(new NopInterceptor()), TestBean.class)).isTrue();
 	}
 
 	@Test
-	public void testPointcutAppliesToOneMethodOnObject() {
+	void testPointcutAppliesToOneMethodOnObject() {
 		class TestPointcut extends StaticMethodMatcherPointcut {
 			@Override
 			public boolean matches(Method method, @Nullable Class<?> clazz) {
@@ -78,7 +84,7 @@ public class AopUtilsTests {
 	 * that's subverted the singleton construction limitation.
 	 */
 	@Test
-	public void testCanonicalFrameworkClassesStillCanonicalOnDeserialization() throws Exception {
+	void testCanonicalFrameworkClassesStillCanonicalOnDeserialization() throws Exception {
 		assertThat(SerializationTestUtils.serializeAndDeserialize(MethodMatcher.TRUE)).isSameAs(MethodMatcher.TRUE);
 		assertThat(SerializationTestUtils.serializeAndDeserialize(ClassFilter.TRUE)).isSameAs(ClassFilter.TRUE);
 		assertThat(SerializationTestUtils.serializeAndDeserialize(Pointcut.TRUE)).isSameAs(Pointcut.TRUE);
@@ -88,4 +94,45 @@ public class AopUtilsTests {
 		assertThat(SerializationTestUtils.serializeAndDeserialize(ExposeInvocationInterceptor.INSTANCE)).isSameAs(ExposeInvocationInterceptor.INSTANCE);
 	}
 
+	@Test
+	void testInvokeJoinpointUsingReflection() throws Throwable {
+		String name = "foo";
+		TestBean testBean = new TestBean(name);
+		Method method = ReflectionUtils.findMethod(TestBean.class, "getName");
+		Object result = AopUtils.invokeJoinpointUsingReflection(testBean, method, new Object[0]);
+		assertThat(result).isEqualTo(name);
+	}
+
+	@Test  // gh-32365
+	void mostSpecificMethodBetweenJdkProxyAndTarget() throws Exception {
+		Class<?> proxyClass = new ProxyFactory(new WithInterface()).getProxy(getClass().getClassLoader()).getClass();
+		Method specificMethod = AopUtils.getMostSpecificMethod(proxyClass.getMethod("handle", List.class), WithInterface.class);
+		assertThat(ResolvableType.forMethodParameter(specificMethod, 0).getGeneric().toClass()).isEqualTo(String.class);
+	}
+
+	@Test  // gh-32365
+	void mostSpecificMethodBetweenCglibProxyAndTarget() throws Exception {
+		Class<?> proxyClass = new ProxyFactory(new WithoutInterface()).getProxy(getClass().getClassLoader()).getClass();
+		Method specificMethod = AopUtils.getMostSpecificMethod(proxyClass.getMethod("handle", List.class), WithoutInterface.class);
+		assertThat(ResolvableType.forMethodParameter(specificMethod, 0).getGeneric().toClass()).isEqualTo(String.class);
+	}
+
+
+	interface ProxyInterface {
+
+		void handle(List<String> list);
+	}
+
+	static class WithInterface implements ProxyInterface {
+
+		public void handle(List<String> list) {
+		}
+	}
+
+	static class WithoutInterface {
+
+		public void handle(List<String> list) {
+		}
+	}
+
 }