annotationdrivenbeandefinitionparser.java

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/*
 * Copyright 2002-2007 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 org.springframework.transaction.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.support.AbstractBeanDefinition;
import org.springframework.beans.factory.support.RootBeanDefinition;
import org.springframework.beans.factory.xml.AbstractBeanDefinitionParser;
import org.springframework.beans.factory.xml.ParserContext;
import org.springframework.transaction.interceptor.TransactionAttributeSourceAdvisor;
import org.springframework.transaction.interceptor.TransactionInterceptor;

/**
 * {@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 Rob Harrop
 * @author Juergen Hoeller
 * @since 2.0
 */
class AnnotationDrivenBeanDefinitionParser extends AbstractBeanDefinitionParser {

	/**
	 * Parses the '<code>&lt;tx:annotation-driven/>&gt;</code>' tag. Will
	 * {@link AopNamespaceUtils#registerAutoProxyCreatorIfNecessary register an AutoProxyCreator} in
	 * the container as necessary.
	 */
	protected AbstractBeanDefinition parseInternal(Element element, ParserContext parserContext) {
		AopNamespaceUtils.registerAutoProxyCreatorIfNecessary(parserContext, element);

		// Create the TransactionInterceptor definition.
		RootBeanDefinition interceptorDef = new RootBeanDefinition(TransactionInterceptor.class);
		interceptorDef.setSource(parserContext.extractSource(element));
		interceptorDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
		String transactionManagerName = (element.hasAttribute(TxNamespaceUtils.TRANSACTION_MANAGER_ATTRIBUTE) ?
				element.getAttribute(TxNamespaceUtils.TRANSACTION_MANAGER_ATTRIBUTE) : "transactionManager");
		interceptorDef.getPropertyValues().addPropertyValue(
				TxNamespaceUtils.TRANSACTION_MANAGER_PROPERTY, new RuntimeBeanReference(transactionManagerName));
		Class sourceClass = TxNamespaceUtils.getAnnotationTransactionAttributeSourceClass();
		interceptorDef.getPropertyValues().addPropertyValue(
				TxNamespaceUtils.TRANSACTION_ATTRIBUTE_SOURCE, new RootBeanDefinition(sourceClass));

		// Create the TransactionAttributeSourceAdvisor definition.
		RootBeanDefinition advisorDef = new RootBeanDefinition(TransactionAttributeSourceAdvisor.class);
		advisorDef.setSource(parserContext.extractSource(element));
		advisorDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
		advisorDef.getPropertyValues().addPropertyValue("transactionInterceptor", interceptorDef);
		if (element.hasAttribute("order")) {
			advisorDef.getPropertyValues().addPropertyValue("order", element.getAttribute("order"));
		}

		return advisorDef;
	}

	protected boolean shouldGenerateId() {
		return true;
	}

}