https://github.com/spring-projects/spring-framework: Spring Context (Spring IO)
  • Juergen Hoeller 
/*
 * Copyright 2002-2018 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.config;

import org.w3c.dom.Element;

import org.springframework.aop.config.AopNamespaceUtils;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.RuntimeBeanReference;
import org.springframework.beans.factory.parsing.BeanComponentDefinition;
import org.springframework.beans.factory.parsing.CompositeComponentDefinition;
import org.springframework.beans.factory.support.RootBeanDefinition;
import org.springframework.beans.factory.xml.BeanDefinitionParser;
import org.springframework.beans.factory.xml.ParserContext;
import org.springframework.cache.interceptor.BeanFactoryCacheOperationSourceAdvisor;
import org.springframework.cache.interceptor.CacheInterceptor;
import org.springframework.lang.Nullable;
import org.springframework.util.ClassUtils;
import org.springframework.util.StringUtils;


BeanDefinitionParser implementation that allows users to easily configure all the infrastructure beans required to enable annotation-driven cache demarcation. 
By default, all proxies are created as JDK proxies. This may cause some problems if you are injecting objects as concrete classes rather than interfaces. To overcome this restriction you can set the 'proxy-target-class' attribute to 'true', which will result in class-based proxies being created. 
If the JSR-107 API and Spring's JCache implementation are present, the necessary infrastructure beans required to handle methods annotated with CacheResult, CachePut, CacheRemove or CacheRemoveAll are also registered. 
Author:Costin Leau, Stephane Nicoll
Since:3.1
/**
 * {@link org.springframework.beans.factory.xml.BeanDefinitionParser}
 * implementation that allows users to easily configure all the
 * infrastructure beans required to enable annotation-driven cache
 * demarcation.
 *
 * <p>By default, all proxies are created as JDK proxies. This may cause
 * some problems if you are injecting objects as concrete classes rather
 * than interfaces. To overcome this restriction you can set the
 * '{@code proxy-target-class}' attribute to '{@code true}', which will
 * result in class-based proxies being created.
 *
 * <p>If the JSR-107 API and Spring's JCache implementation are present,
 * the necessary infrastructure beans required to handle methods annotated
 * with {@code CacheResult}, {@code CachePut}, {@code CacheRemove} or
 * {@code CacheRemoveAll} are also registered.
 *
 * @author Costin Leau
 * @author Stephane Nicoll
 * @since 3.1
 */
class AnnotationDrivenCacheBeanDefinitionParser implements BeanDefinitionParser {

	private static final String CACHE_ASPECT_CLASS_NAME =
			"org.springframework.cache.aspectj.AnnotationCacheAspect";

	private static final String JCACHE_ASPECT_CLASS_NAME =
			"org.springframework.cache.aspectj.JCacheCacheAspect";

	private static final boolean jsr107Present;

	private static final boolean jcacheImplPresent;

	static {
		ClassLoader classLoader = AnnotationDrivenCacheBeanDefinitionParser.class.getClassLoader();
		jsr107Present = ClassUtils.isPresent("javax.cache.Cache", classLoader);
		jcacheImplPresent = ClassUtils.isPresent(
				"org.springframework.cache.jcache.interceptor.DefaultJCacheOperationSource", classLoader);
	}


	
Parses the '<cache:annotation-driven>' tag. Will 
register an AutoProxyCreator with the container as necessary. 
/**
	 * Parses the '{@code <cache:annotation-driven>}' tag. Will
	 * {@link AopNamespaceUtils#registerAutoProxyCreatorIfNecessary
	 * register an AutoProxyCreator} with the container as necessary.
	 */
	@Override
	@Nullable
	public BeanDefinition parse(Element element, ParserContext parserContext) {
		String mode = element.getAttribute("mode");
		if ("aspectj".equals(mode)) {
			// mode="aspectj"
			registerCacheAspect(element, parserContext);
		}
		else {
			// mode="proxy"
			registerCacheAdvisor(element, parserContext);
		}

		return null;
	}

	private void registerCacheAspect(Element element, ParserContext parserContext) {
		SpringCachingConfigurer.registerCacheAspect(element, parserContext);
		if (jsr107Present && jcacheImplPresent) {
			JCacheCachingConfigurer.registerCacheAspect(element, parserContext);
		}
	}

	private void registerCacheAdvisor(Element element, ParserContext parserContext) {
		AopNamespaceUtils.registerAutoProxyCreatorIfNecessary(parserContext, element);
		SpringCachingConfigurer.registerCacheAdvisor(element, parserContext);
		if (jsr107Present && jcacheImplPresent) {
			JCacheCachingConfigurer.registerCacheAdvisor(element, parserContext);
		}
	}

	
Parse the cache resolution strategy to use. If a 'cache-resolver' attribute is set, it is injected. Otherwise the 'cache-manager' is set. If setBoth is true, both service are actually injected. 
/**
	 * Parse the cache resolution strategy to use. If a 'cache-resolver' attribute
	 * is set, it is injected. Otherwise the 'cache-manager' is set. If {@code setBoth}
	 * is {@code true}, both service are actually injected.
	 */
	private static void parseCacheResolution(Element element, BeanDefinition def, boolean setBoth) {
		String name = element.getAttribute("cache-resolver");
		boolean hasText = StringUtils.hasText(name);
		if (hasText) {
			def.getPropertyValues().add("cacheResolver", new RuntimeBeanReference(name.trim()));
		}
		if (!hasText || setBoth) {
			def.getPropertyValues().add("cacheManager",
					new RuntimeBeanReference(CacheNamespaceHandler.extractCacheManager(element)));
		}
	}

	private static void parseErrorHandler(Element element, BeanDefinition def) {
		String name = element.getAttribute("error-handler");
		if (StringUtils.hasText(name)) {
			def.getPropertyValues().add("errorHandler", new RuntimeBeanReference(name.trim()));
		}
	}


	
Configure the necessary infrastructure to support the Spring's caching annotations.

/**
	 * Configure the necessary infrastructure to support the Spring's caching annotations.
	 */
	private static class SpringCachingConfigurer {

		private static void registerCacheAdvisor(Element element, ParserContext parserContext) {
			if (!parserContext.getRegistry().containsBeanDefinition(CacheManagementConfigUtils.CACHE_ADVISOR_BEAN_NAME)) {
				Object eleSource = parserContext.extractSource(element);

				// Create the CacheOperationSource definition.
				RootBeanDefinition sourceDef = new RootBeanDefinition("org.springframework.cache.annotation.AnnotationCacheOperationSource");
				sourceDef.setSource(eleSource);
				sourceDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
				String sourceName = parserContext.getReaderContext().registerWithGeneratedName(sourceDef);

				// Create the CacheInterceptor definition.
				RootBeanDefinition interceptorDef = new RootBeanDefinition(CacheInterceptor.class);
				interceptorDef.setSource(eleSource);
				interceptorDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
				parseCacheResolution(element, interceptorDef, false);
				parseErrorHandler(element, interceptorDef);
				CacheNamespaceHandler.parseKeyGenerator(element, interceptorDef);
				interceptorDef.getPropertyValues().add("cacheOperationSources", new RuntimeBeanReference(sourceName));
				String interceptorName = parserContext.getReaderContext().registerWithGeneratedName(interceptorDef);

				// Create the CacheAdvisor definition.
				RootBeanDefinition advisorDef = new RootBeanDefinition(BeanFactoryCacheOperationSourceAdvisor.class);
				advisorDef.setSource(eleSource);
				advisorDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
				advisorDef.getPropertyValues().add("cacheOperationSource", new RuntimeBeanReference(sourceName));
				advisorDef.getPropertyValues().add("adviceBeanName", interceptorName);
				if (element.hasAttribute("order")) {
					advisorDef.getPropertyValues().add("order", element.getAttribute("order"));
				}
				parserContext.getRegistry().registerBeanDefinition(CacheManagementConfigUtils.CACHE_ADVISOR_BEAN_NAME, advisorDef);

				CompositeComponentDefinition compositeDef = new CompositeComponentDefinition(element.getTagName(), eleSource);
				compositeDef.addNestedComponent(new BeanComponentDefinition(sourceDef, sourceName));
				compositeDef.addNestedComponent(new BeanComponentDefinition(interceptorDef, interceptorName));
				compositeDef.addNestedComponent(new BeanComponentDefinition(advisorDef, CacheManagementConfigUtils.CACHE_ADVISOR_BEAN_NAME));
				parserContext.registerComponent(compositeDef);
			}
		}

		
Registers a cache aspect.

<bean id="cacheAspect" class="org.springframework.cache.aspectj.AnnotationCacheAspect" factory-method="aspectOf">
  <property name="cacheManager" ref="cacheManager"/>
  <property name="keyGenerator" ref="keyGenerator"/>
</bean>



/**
		 * Registers a cache aspect.
		 * <pre class="code">
		 * &lt;bean id="cacheAspect" class="org.springframework.cache.aspectj.AnnotationCacheAspect" factory-method="aspectOf"&gt;
		 *   &lt;property name="cacheManager" ref="cacheManager"/&gt;
		 *   &lt;property name="keyGenerator" ref="keyGenerator"/&gt;
		 * &lt;/bean&gt;
		 * </pre>
		 */
		private static void registerCacheAspect(Element element, ParserContext parserContext) {
			if (!parserContext.getRegistry().containsBeanDefinition(CacheManagementConfigUtils.CACHE_ASPECT_BEAN_NAME)) {
				RootBeanDefinition def = new RootBeanDefinition();
				def.setBeanClassName(CACHE_ASPECT_CLASS_NAME);
				def.setFactoryMethodName("aspectOf");
				parseCacheResolution(element, def, false);
				CacheNamespaceHandler.parseKeyGenerator(element, def);
				parserContext.registerBeanComponent(new BeanComponentDefinition(def, CacheManagementConfigUtils.CACHE_ASPECT_BEAN_NAME));
			}
		}
	}


	
Configure the necessary infrastructure to support the standard JSR-107 caching annotations.

/**
	 * Configure the necessary infrastructure to support the standard JSR-107 caching annotations.
	 */
	private static class JCacheCachingConfigurer {

		private static void registerCacheAdvisor(Element element, ParserContext parserContext) {
			if (!parserContext.getRegistry().containsBeanDefinition(CacheManagementConfigUtils.JCACHE_ADVISOR_BEAN_NAME)) {
				Object source = parserContext.extractSource(element);

				// Create the CacheOperationSource definition.
				BeanDefinition sourceDef = createJCacheOperationSourceBeanDefinition(element, source);
				String sourceName = parserContext.getReaderContext().registerWithGeneratedName(sourceDef);

				// Create the CacheInterceptor definition.
				RootBeanDefinition interceptorDef =
						new RootBeanDefinition("org.springframework.cache.jcache.interceptor.JCacheInterceptor");
				interceptorDef.setSource(source);
				interceptorDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
				interceptorDef.getPropertyValues().add("cacheOperationSource", new RuntimeBeanReference(sourceName));
				parseErrorHandler(element, interceptorDef);
				String interceptorName = parserContext.getReaderContext().registerWithGeneratedName(interceptorDef);

				// Create the CacheAdvisor definition.
				RootBeanDefinition advisorDef = new RootBeanDefinition(
						"org.springframework.cache.jcache.interceptor.BeanFactoryJCacheOperationSourceAdvisor");
				advisorDef.setSource(source);
				advisorDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
				advisorDef.getPropertyValues().add("cacheOperationSource", new RuntimeBeanReference(sourceName));
				advisorDef.getPropertyValues().add("adviceBeanName", interceptorName);
				if (element.hasAttribute("order")) {
					advisorDef.getPropertyValues().add("order", element.getAttribute("order"));
				}
				parserContext.getRegistry().registerBeanDefinition(CacheManagementConfigUtils.JCACHE_ADVISOR_BEAN_NAME, advisorDef);

				CompositeComponentDefinition compositeDef = new CompositeComponentDefinition(element.getTagName(), source);
				compositeDef.addNestedComponent(new BeanComponentDefinition(sourceDef, sourceName));
				compositeDef.addNestedComponent(new BeanComponentDefinition(interceptorDef, interceptorName));
				compositeDef.addNestedComponent(new BeanComponentDefinition(advisorDef, CacheManagementConfigUtils.JCACHE_ADVISOR_BEAN_NAME));
				parserContext.registerComponent(compositeDef);
			}
		}

		private static void registerCacheAspect(Element element, ParserContext parserContext) {
			if (!parserContext.getRegistry().containsBeanDefinition(CacheManagementConfigUtils.JCACHE_ASPECT_BEAN_NAME)) {
				Object eleSource = parserContext.extractSource(element);
				RootBeanDefinition def = new RootBeanDefinition();
				def.setBeanClassName(JCACHE_ASPECT_CLASS_NAME);
				def.setFactoryMethodName("aspectOf");
				BeanDefinition sourceDef = createJCacheOperationSourceBeanDefinition(element, eleSource);
				String sourceName =
						parserContext.getReaderContext().registerWithGeneratedName(sourceDef);
				def.getPropertyValues().add("cacheOperationSource", new RuntimeBeanReference(sourceName));

				parserContext.registerBeanComponent(new BeanComponentDefinition(sourceDef, sourceName));
				parserContext.registerBeanComponent(new BeanComponentDefinition(def, CacheManagementConfigUtils.JCACHE_ASPECT_BEAN_NAME));
			}
		}

		private static RootBeanDefinition createJCacheOperationSourceBeanDefinition(Element element, @Nullable Object eleSource) {
			RootBeanDefinition sourceDef =
					new RootBeanDefinition("org.springframework.cache.jcache.interceptor.DefaultJCacheOperationSource");
			sourceDef.setSource(eleSource);
			sourceDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
			// JSR-107 support should create an exception cache resolver with the cache manager
			// and there is no way to set that exception cache resolver from the namespace
			parseCacheResolution(element, sourceDef, true);
			CacheNamespaceHandler.parseKeyGenerator(element, sourceDef);
			return sourceDef;
		}
	}

}