AnnotationDrivenBeanDefinitionParser.java

/*
 * Copyright 2002-2009 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
 *
 *      http://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 cn.org.rapid_framework.cache.aop.config;

import org.springframework.aop.config.AopNamespaceUtils;
import org.springframework.beans.factory.config.BeanDefinition;
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.w3c.dom.Element;

import cn.org.rapid_framework.cache.aop.advice.AnnotationMethodCacheAdvice;
import cn.org.rapid_framework.cache.aop.interceptor.AnnotationMethodCacheInterceptor;

/**
 * {@link org.springframework.beans.factory.xml.BeanDefinitionParser}
 * implementation that allows users to easily configure all the infrastructure
 * beans required to enable annotation-driven transaction 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</code>' attribute to '<code>true</code>', which
 * will result in class-based proxies being created.
 *
 * @author Juergen Hoeller
 * @author Rob Harrop
 * @since 2.0
 */
class AnnotationDrivenBeanDefinitionParser  implements BeanDefinitionParser {

	public static final String METHOD_CACHE_ADVICE_BEAN_NAME =
			"cn.org.rapid_framework.cache.aop.config.internalMethodCacheAdvice";

	/**
	 * Parses the '<code><method-cache:annotation-driven/></code>' tag. Will
	 * {@link AopNamespaceUtils#registerAutoProxyCreatorIfNecessary register an AutoProxyCreator}
	 * with the container as necessary.
	 */
	public BeanDefinition parse(Element element, ParserContext parserContext) {
		AopAutoProxyConfigurer.configureAutoProxyCreator(element, parserContext);
		return null;
	}
	
	/**
	 * Inner class to just introduce an AOP framework dependency when actually in proxy mode.
	 */
	private static class AopAutoProxyConfigurer {

		public static void configureAutoProxyCreator(Element element, ParserContext parserContext) {
			AopNamespaceUtils.registerAutoProxyCreatorIfNecessary(parserContext, element);

			if (!parserContext.getRegistry().containsBeanDefinition(METHOD_CACHE_ADVICE_BEAN_NAME)) {
				Object eleSource = parserContext.extractSource(element);

				// Create the AnnotationMethodCacheInterceptor definition.
				RootBeanDefinition interceptorDef = createAnnotationMethodCacheInterceptorDefinition(element, eleSource);
				String interceptorName = parserContext.getReaderContext().registerWithGeneratedName(interceptorDef);
				
				// Create the AnnotationMethodCacheAdvice definition.
				RootBeanDefinition adviceDef = createAnnotationMethodCacheAdviceDefinition(element,eleSource,interceptorName);
				parserContext.getRegistry().registerBeanDefinition(METHOD_CACHE_ADVICE_BEAN_NAME, adviceDef);
				
				//此处代码无用,只是注册了一个 tagName的CompositeComponentDefinition
				CompositeComponentDefinition compositeDef = new CompositeComponentDefinition(element.getTagName(), eleSource);
				compositeDef.addNestedComponent(new BeanComponentDefinition(adviceDef, METHOD_CACHE_ADVICE_BEAN_NAME));
				compositeDef.addNestedComponent(new BeanComponentDefinition(interceptorDef, interceptorName));
				parserContext.registerComponent(compositeDef);
				
			}
		}

		private static RootBeanDefinition createAnnotationMethodCacheInterceptorDefinition(
				Element element, Object eleSource) {
			RootBeanDefinition interceptorDef = new RootBeanDefinition(AnnotationMethodCacheInterceptor.class);
			interceptorDef.setSource(eleSource);
			interceptorDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
			interceptorDef.getPropertyValues().add("methodCacheBeanName",MethodCacheNamespaceHandler.getMethodCacheName(element));
			return interceptorDef;
		}

		private static RootBeanDefinition createAnnotationMethodCacheAdviceDefinition(
				Element element, Object eleSource,String annotationMethodCacheInterceptorBeanName) {
			RootBeanDefinition def = new RootBeanDefinition(AnnotationMethodCacheAdvice.class);
			def.setSource(eleSource);
			def.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
			def.getPropertyValues().add("annotationMethodCacheInterceptorBeanName",annotationMethodCacheInterceptorBeanName);
			return def;
		}
		
		
	}

}