Allow ReflectionHints to register hints on interface hierarchies

This commit promotes a previously private method in
`BeanRegistrationsAotContribution` to a top-level method in
`ReflectionHints`.

This helps to register hints on all interfaces implemented in the class
hierarchy of the given type.

Closes gh-32824

Author: bclozel

spring-beans/src/main/java/org/springframework/beans/factory/aot/BeanRegistrationsAotContribution.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.
@@ -33,7 +33,6 @@
 import org.springframework.javapoet.ClassName;
 import org.springframework.javapoet.CodeBlock;
 import org.springframework.javapoet.MethodSpec;
-import org.springframework.util.ClassUtils;
 
 /**
  * AOT contribution from a {@link BeanRegistrationsAotProcessor} used to
@@ -115,23 +114,10 @@ private void generateRegisterHints(RuntimeHints runtimeHints, Map<BeanRegistrati
 			ReflectionHints hints = runtimeHints.reflection();
 			Class<?> beanClass = beanRegistrationKey.beanClass();
 			hints.registerType(beanClass, MemberCategory.INTROSPECT_PUBLIC_METHODS, MemberCategory.INTROSPECT_DECLARED_METHODS);
-			introspectPublicMethodsOnAllInterfaces(hints, beanClass);
+			hints.registerForInterfaces(beanClass, typeHint -> typeHint.withMembers(MemberCategory.INTROSPECT_PUBLIC_METHODS));
 		});
 	}
 
-	private void introspectPublicMethodsOnAllInterfaces(ReflectionHints hints, Class<?> type) {
-		Class<?> currentClass = type;
-		while (currentClass != null && currentClass != Object.class) {
-			for (Class<?> interfaceType : currentClass.getInterfaces()) {
-				if (!ClassUtils.isJavaLanguageInterface(interfaceType)) {
-					hints.registerType(interfaceType, MemberCategory.INTROSPECT_PUBLIC_METHODS);
-					introspectPublicMethodsOnAllInterfaces(hints, interfaceType);
-				}
-			}
-			currentClass = currentClass.getSuperclass();
-		}
-	}
-
 	/**
 	 * Gather the necessary information to register a particular bean.
 	 * @param methodGenerator the {@link BeanDefinitionMethodGenerator} to use

spring-core/src/main/java/org/springframework/aot/hint/ReflectionHints.java

@@ -175,6 +175,28 @@ public ReflectionHints registerTypes(Iterable<TypeReference> types, Consumer<Typ
 		return this;
 	}
 
+	/**
+	 * Register or customize reflection hints for all the interfaces implemented by
+	 * the given type and its parent classes, ignoring the common Java language interfaces.
+	 * The specified {@code typeHint} consumer is invoked for each type.
+	 * @param type the type to consider
+	 * @param typeHint a builder to further customize hints for each type
+	 * @return {@code this}, to facilitate method chaining
+	 */
+	public ReflectionHints registerForInterfaces(Class<?> type, Consumer<TypeHint.Builder> typeHint) {
+		Class<?> currentClass = type;
+		while (currentClass != null && currentClass != Object.class) {
+			for (Class<?> interfaceType : currentClass.getInterfaces()) {
+				if (!ClassUtils.isJavaLanguageInterface(interfaceType)) {
+					this.registerType(interfaceType, typeHint);
+					registerForInterfaces(interfaceType, typeHint);
+				}
+			}
+			currentClass = currentClass.getSuperclass();
+		}
+		return this;
+	}
+
 	/**
 	 * Register the need for reflection on the specified {@link Field}.
 	 * @param field the field that requires reflection

spring-core/src/test/java/org/springframework/aot/hint/ReflectionHintsTests.java

@@ -16,6 +16,7 @@
 
 package org.springframework.aot.hint;
 
+import java.io.Serializable;
 import java.lang.reflect.Constructor;
 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
@@ -209,6 +210,18 @@ void registerMethodTwiceUpdatesExistingEntry() {
 		});
 	}
 
+	@Test
+	void registerOnInterfaces() {
+		this.reflectionHints.registerForInterfaces(ChildType.class,
+				typeHint -> typeHint.withMembers(MemberCategory.INTROSPECT_PUBLIC_METHODS));
+		assertThat(this.reflectionHints.typeHints()).hasSize(2)
+				.noneMatch(typeHint -> typeHint.getType().getCanonicalName().equals(Serializable.class.getCanonicalName()))
+				.anyMatch(typeHint -> typeHint.getType().getCanonicalName().equals(SecondInterface.class.getCanonicalName())
+						&& typeHint.getMemberCategories().contains(MemberCategory.INTROSPECT_PUBLIC_METHODS))
+				.anyMatch(typeHint -> typeHint.getType().getCanonicalName().equals(FirstInterface.class.getCanonicalName())
+						&& typeHint.getMemberCategories().contains(MemberCategory.INTROSPECT_PUBLIC_METHODS));
+	}
+
 	private void assertTestTypeMethodHints(Consumer<ExecutableHint> methodHint) {
 		assertThat(this.reflectionHints.typeHints()).singleElement().satisfies(typeHint -> {
 			assertThat(typeHint.getType().getCanonicalName()).isEqualTo(TestType.class.getCanonicalName());
@@ -241,4 +254,28 @@ void setName(String name) {
 
 	}
 
+	interface FirstInterface {
+		void first();
+	}
+
+	interface SecondInterface {
+		void second();
+	}
+
+	@SuppressWarnings("serial")
+	static class ParentType implements Serializable, FirstInterface {
+		@Override
+		public void first() {
+
+		}
+	}
+
+	@SuppressWarnings("serial")
+	static class ChildType extends ParentType implements SecondInterface {
+		@Override
+		public void second() {
+
+		}
+	}
+
 }