<tx:annotation-driven /> 标签解析

 <tx:annotation-driven /> 开启对@Transaction 注解事物支持由TxNamespaceHandler负责解析

主要代码如下

public static void configureAutoProxyCreator(Element element, ParserContext parserContext) {
//AnnotationAwareAspectJAutoProxyCreator

			
AopNamespaceUtils.registerAutoProxyCreatorIfNecessary(parserContext, element);

			String txAdvisorBeanName = TransactionManagementConfigUtils.TRANSACTION_ADVISOR_BEAN_NAME;
			if (!parserContext.getRegistry().containsBeanDefinition(txAdvisorBeanName)) {
				Object eleSource = parserContext.extractSource(element);

				//负责解析@Transaction注解获取事物属性
				RootBeanDefinition sourceDef = new RootBeanDefinition(AnnotationTransactionAttributeSource.class);
				sourceDef.setSource(eleSource);
				sourceDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
				String sourceName = parserContext.getReaderContext().registerWithGeneratedName(sourceDef);

				// 事物拦截器，负责事物开启关闭等动作
				RootBeanDefinition interceptorDef = new RootBeanDefinition(TransactionInterceptor.class);
				interceptorDef.setSource(eleSource);
				interceptorDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
				registerTransactionManager(element, interceptorDef);
				interceptorDef.getPropertyValues().add("transactionAttributeSource", new RuntimeBeanReference(sourceName));
				String interceptorName = parserContext.getReaderContext().registerWithGeneratedName(interceptorDef);

				// Create the TransactionAttributeSourceAdvisor definition.
				RootBeanDefinition advisorDef = new RootBeanDefinition(BeanFactoryTransactionAttributeSourceAdvisor.class);
				advisorDef.setSource(eleSource);
				advisorDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
				advisorDef.getPropertyValues().add("transactionAttributeSource", new RuntimeBeanReference(sourceName));
				advisorDef.getPropertyValues().add("adviceBeanName", interceptorName);
				if (element.hasAttribute("order")) {
					advisorDef.getPropertyValues().add("order", element.getAttribute("order"));
				}
				parserContext.getRegistry().registerBeanDefinition(txAdvisorBeanName, 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, txAdvisorBeanName));
				parserContext.registerComponent(compositeDef);
			}
		}