Fix ReflectionUtils#getDeclaredMethods to provide consistent result

spring-core/src/main/java/org/springframework/util/ReflectionUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 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.
@@ -41,6 +41,7 @@
  * @author Costin Leau
  * @author Sam Brannen
  * @author Chris Beams
+ * @author Yong-Hyun Kim
  * @since 1.2.2
  */
 public abstract class ReflectionUtils {
@@ -463,6 +464,7 @@ private static Method[] getDeclaredMethods(Class<?> clazz, boolean defensive) {
 		if (result == null) {
 			try {
 				Method[] declaredMethods = clazz.getDeclaredMethods();
+				Arrays.sort(declaredMethods, ReflectionUtils::methodDeclaringClassHierarchySorter);
 				List<Method> defaultMethods = findDefaultMethodsOnInterfaces(clazz);
 				if (defaultMethods != null) {
 					result = new Method[declaredMethods.length + defaultMethods.size()];
@@ -486,6 +488,18 @@ private static Method[] getDeclaredMethods(Class<?> clazz, boolean defensive) {
 		return (result.length == 0 || !defensive) ? result : result.clone();
 	}
 
+	private static int methodDeclaringClassHierarchySorter(Method method1, Method method2) {
+		Class<?> clazz1 = method1.getDeclaringClass();
+		Class<?> clazz2 = method2.getDeclaringClass();
+		if (clazz1 == clazz2) {
+			return 0;
+		}
+		if (clazz1.isAssignableFrom(clazz2)) {
+			return 1;
+		}
+		return -1;
+	}
+
 	@Nullable
 	private static List<Method> findDefaultMethodsOnInterfaces(Class<?> clazz) {
 		List<Method> result = null;

spring-core/src/test/java/org/springframework/util/ReflectionUtilsTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 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.
@@ -37,6 +37,7 @@
  * @author Juergen Hoeller
  * @author Sam Brannen
  * @author Arjen Poutsma
+ * @author Yong-Hyun Kim
  */
 class ReflectionUtilsTests {
 
@@ -231,6 +232,8 @@ void findMethod() {
 		assertThat(ReflectionUtils.findMethod(B.class, "bar", String.class)).isNotNull();
 		assertThat(ReflectionUtils.findMethod(B.class, "foo", Integer.class)).isNotNull();
 		assertThat(ReflectionUtils.findMethod(B.class, "getClass")).isNotNull();
+		assertThat(ReflectionUtils.findMethod(B.class, "baz", String[].class).isBridge()).isFalse();
+		assertThat(ReflectionUtils.findMethod(B.class, "baz", String[].class).isVarArgs()).isTrue();
 	}
 
 	@Test
@@ -381,6 +384,10 @@ private static class A {
 		@SuppressWarnings({ "unused", "RedundantThrows" })
 		private void foo(Integer i) throws RemoteException {
 		}
+
+		protected Object baz(String... args) {
+			return "A";
+		}
 	}
 
 	@SuppressWarnings("unused")
@@ -396,6 +403,11 @@ int add(int... args) {
 			}
 			return sum;
 		}
+
+		@Override
+		protected String baz(String... args) {
+			return "B";
+		}
 	}
 
 }