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));
+	}
+}

spring-context/src/main/resources/META-INF/spring/aot.factories

@@ -1,2 +1,3 @@
 org.springframework.beans.factory.aot.BeanRegistrationAotProcessor= \
-org.springframework.context.aot.ReflectiveProcessorBeanRegistrationAotProcessor
+org.springframework.context.aot.ReflectiveProcessorBeanRegistrationAotProcessor,\
+org.springframework.cache.annotation.CachingBeanRegistrationAotProcessor

spring-context/src/test/java/org/springframework/cache/annotation/CachingBeanRegistrationAotProcessorTests.java

@@ -0,0 +1,111 @@
+/*
+ * 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 org.junit.jupiter.api.Test;
+
+import org.springframework.aop.config.AopConfigUtils;
+import org.springframework.aop.framework.AopProxyUtils;
+import org.springframework.aot.generate.GenerationContext;
+import org.springframework.aot.hint.RuntimeHints;
+import org.springframework.aot.hint.predicate.RuntimeHintsPredicates;
+import org.springframework.beans.factory.aot.BeanRegistrationAotContribution;
+import org.springframework.beans.factory.aot.BeanRegistrationAotProcessor;
+import org.springframework.beans.factory.aot.BeanRegistrationCode;
+import org.springframework.beans.factory.support.DefaultListableBeanFactory;
+import org.springframework.beans.factory.support.RegisteredBean;
+import org.springframework.beans.factory.support.RootBeanDefinition;
+import org.springframework.core.testfixture.aot.generate.TestGenerationContext;
+import org.springframework.lang.Nullable;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.mock;
+
+/**
+ * Tests for {@link CachingBeanRegistrationAotProcessor}.
+ *
+ * @author Sebastien Deleuze
+ */
+public class CachingBeanRegistrationAotProcessorTests {
+
+	BeanRegistrationAotProcessor processor = new CachingBeanRegistrationAotProcessor();
+
+	GenerationContext generationContext = new TestGenerationContext();
+
+
+	@Test
+	void ignoresNonCachingBean() {
+		assertThat(createContribution(NonCaching.class, false)).isNull();
+	}
+
+	@Test
+	void contributesProxyForCacheableInterface() {
+		process(CacheableServiceImpl.class, false);
+		RuntimeHints runtimeHints = this.generationContext.getRuntimeHints();
+		assertThat(RuntimeHintsPredicates.proxies().forInterfaces(AopProxyUtils.completeJdkProxyInterfaces(CacheableServiceInterface.class))).accepts(runtimeHints);
+	}
+
+	@Test
+	void ignoresProxyForCacheableInterfaceWithClassProxying() {
+		assertThat(createContribution(CacheableServiceImpl.class, true)).isNull();
+	}
+
+	@Test
+	void ignoresProxyForCacheableClass() {
+		assertThat(createContribution(CacheableService.class, true)).isNull();
+	}
+
+	@Nullable
+	private BeanRegistrationAotContribution createContribution(Class<?> beanClass, boolean forceClassProxying) {
+		DefaultListableBeanFactory beanFactory = new DefaultListableBeanFactory();
+		if (forceClassProxying) {
+			AopConfigUtils.registerAutoProxyCreatorIfNecessary(beanFactory);
+			AopConfigUtils.forceAutoProxyCreatorToUseClassProxying(beanFactory);
+		}
+		beanFactory.registerBeanDefinition(beanClass.getName(), new RootBeanDefinition(beanClass));
+		return this.processor.processAheadOfTime(RegisteredBean.of(beanFactory, beanClass.getName()));
+	}
+
+	private void process(Class<?> beanClass, boolean forceClassProxying) {
+		BeanRegistrationAotContribution contribution = createContribution(beanClass, forceClassProxying);
+		assertThat(contribution).isNotNull();
+		contribution.applyTo(this.generationContext, mock(BeanRegistrationCode.class));
+	}
+
+	static class NonCaching {
+	}
+
+	interface CacheableServiceInterface {
+
+		@Cacheable
+		void invoke();
+	}
+
+	class CacheableServiceImpl implements CacheableServiceInterface {
+
+		@Override
+		public void invoke() {
+		}
+	}
+
+	class CacheableService {
+
+		@Cacheable
+		public void invoke() {
+		}
+	}
+}