Introduce CachingBeanRegistrationAotProcessor

It contributes proxy hints for interfaces when class
proxying is not forced.

Closes gh-28943

spring-context/src/main/java/org/springframework/cache/annotation/CachingBeanRegistrationAotProcessor.java

@@ -0,0 +1,93 @@
+/*
+ * Copyright 2002-2022 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.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.cache.annotation;
+
+import java.lang.annotation.Annotation;
+import java.lang.reflect.AnnotatedElement;
+import java.util.LinkedHashSet;
+import java.util.Set;
+
+import org.springframework.aop.config.AopConfigUtils;
+import org.springframework.aop.framework.AopProxyUtils;
+import org.springframework.aot.hint.RuntimeHints;
+import org.springframework.beans.factory.aot.BeanRegistrationAotContribution;
+import org.springframework.beans.factory.aot.BeanRegistrationAotProcessor;
+import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
+import org.springframework.beans.factory.support.RegisteredBean;
+import org.springframework.core.annotation.AnnotationUtils;
+import org.springframework.core.annotation.MergedAnnotations;
+import org.springframework.util.ClassUtils;
+import org.springframework.util.ReflectionUtils;
+
+/**
+ * {@link BeanRegistrationAotProcessor} to register runtime hints for beans that use caching annotations to
+ * enable JDK proxy creation when needed.
+ *
+ * @author Sebastien Deleuze
+ * @since 6.0
+ */
+public class CachingBeanRegistrationAotProcessor implements BeanRegistrationAotProcessor {
+
+	private static final Set<Class<? extends Annotation>> CACHE_OPERATION_ANNOTATIONS = new LinkedHashSet<>(8);
+
+	static {
+		CACHE_OPERATION_ANNOTATIONS.add(Cacheable.class);
+		CACHE_OPERATION_ANNOTATIONS.add(CacheEvict.class);
+		CACHE_OPERATION_ANNOTATIONS.add(CachePut.class);
+		CACHE_OPERATION_ANNOTATIONS.add(Caching.class);
+	}
+
+	@Override
+	public BeanRegistrationAotContribution processAheadOfTime(RegisteredBean registeredBean) {
+		if (isCaching(registeredBean.getBeanClass()) && !isClassProxyingForced(registeredBean.getBeanFactory())) {
+			return (generationContext, beanRegistrationCode) -> registerSpringProxy(registeredBean.getBeanClass(),
+					generationContext.getRuntimeHints());
+		}
+		return null;
+	}
+
+	private static boolean isClassProxyingForced(ConfigurableListableBeanFactory beanFactory) {
+		return beanFactory.containsBean(AopConfigUtils.AUTO_PROXY_CREATOR_BEAN_NAME) &&
+				Boolean.TRUE.equals(beanFactory.getBeanDefinition(AopConfigUtils.AUTO_PROXY_CREATOR_BEAN_NAME)
+						.getPropertyValues().get("proxyTargetClass"));
+	}
+
+	private boolean isCaching(Class<?> beanClass) {
+		if (!AnnotationUtils.isCandidateClass(beanClass, CACHE_OPERATION_ANNOTATIONS)) {
+			return false;
+		}
+		Set<AnnotatedElement> elements = new LinkedHashSet<>();
+		elements.add(beanClass);
+		ReflectionUtils.doWithMethods(beanClass, elements::add);
+		for (Class<?> interfaceClass : ClassUtils.getAllInterfacesForClass(beanClass)) {
+			elements.add(interfaceClass);
+			ReflectionUtils.doWithMethods(interfaceClass, elements::add);
+		}
+		return elements.stream().anyMatch(element -> {
+			MergedAnnotations mergedAnnotations = MergedAnnotations.from(element, MergedAnnotations.SearchStrategy.TYPE_HIERARCHY);
+			return CACHE_OPERATION_ANNOTATIONS.stream().anyMatch(mergedAnnotations::isPresent);
+		});
+	}
+
+	private static void registerSpringProxy(Class<?> type, RuntimeHints runtimeHints) {
+		Class<?>[] proxyInterfaces = ClassUtils.getAllInterfacesForClass(type);
+		if (proxyInterfaces.length == 0) {
+			return;
+		}
+		runtimeHints.proxies().registerJdkProxy(AopProxyUtils.completeJdkProxyInterfaces(proxyInterfaces));
+	}
+}