001/*
002 * Copyright 2002-2018 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.aop.config;
018
019import org.w3c.dom.Element;
020
021import org.springframework.beans.factory.config.BeanDefinition;
022import org.springframework.beans.factory.parsing.BeanComponentDefinition;
023import org.springframework.beans.factory.support.BeanDefinitionRegistry;
024import org.springframework.beans.factory.xml.ParserContext;
025import org.springframework.lang.Nullable;
026
027/**
028 * Utility class for handling registration of auto-proxy creators used internally
029 * by the '{@code aop}' namespace tags.
030 *
031 * <p>Only a single auto-proxy creator should be registered and multiple configuration
032 * elements may wish to register different concrete implementations. As such this class
033 * delegates to {@link AopConfigUtils} which provides a simple escalation protocol.
034 * Callers may request a particular auto-proxy creator and know that creator,
035 * <i>or a more capable variant thereof</i>, will be registered as a post-processor.
036 *
037 * @author Rob Harrop
038 * @author Juergen Hoeller
039 * @author Mark Fisher
040 * @since 2.0
041 * @see AopConfigUtils
042 */
043public abstract class AopNamespaceUtils {
044
045        /**
046         * The {@code proxy-target-class} attribute as found on AOP-related XML tags.
047         */
048        public static final String PROXY_TARGET_CLASS_ATTRIBUTE = "proxy-target-class";
049
050        /**
051         * The {@code expose-proxy} attribute as found on AOP-related XML tags.
052         */
053        private static final String EXPOSE_PROXY_ATTRIBUTE = "expose-proxy";
054
055
056        public static void registerAutoProxyCreatorIfNecessary(
057                        ParserContext parserContext, Element sourceElement) {
058
059                BeanDefinition beanDefinition = AopConfigUtils.registerAutoProxyCreatorIfNecessary(
060                                parserContext.getRegistry(), parserContext.extractSource(sourceElement));
061                useClassProxyingIfNecessary(parserContext.getRegistry(), sourceElement);
062                registerComponentIfNecessary(beanDefinition, parserContext);
063        }
064
065        public static void registerAspectJAutoProxyCreatorIfNecessary(
066                        ParserContext parserContext, Element sourceElement) {
067
068                BeanDefinition beanDefinition = AopConfigUtils.registerAspectJAutoProxyCreatorIfNecessary(
069                                parserContext.getRegistry(), parserContext.extractSource(sourceElement));
070                useClassProxyingIfNecessary(parserContext.getRegistry(), sourceElement);
071                registerComponentIfNecessary(beanDefinition, parserContext);
072        }
073
074        public static void registerAspectJAnnotationAutoProxyCreatorIfNecessary(
075                        ParserContext parserContext, Element sourceElement) {
076
077                BeanDefinition beanDefinition = AopConfigUtils.registerAspectJAnnotationAutoProxyCreatorIfNecessary(
078                                parserContext.getRegistry(), parserContext.extractSource(sourceElement));
079                useClassProxyingIfNecessary(parserContext.getRegistry(), sourceElement);
080                registerComponentIfNecessary(beanDefinition, parserContext);
081        }
082
083        private static void useClassProxyingIfNecessary(BeanDefinitionRegistry registry, @Nullable Element sourceElement) {
084                if (sourceElement != null) {
085                        boolean proxyTargetClass = Boolean.parseBoolean(sourceElement.getAttribute(PROXY_TARGET_CLASS_ATTRIBUTE));
086                        if (proxyTargetClass) {
087                                AopConfigUtils.forceAutoProxyCreatorToUseClassProxying(registry);
088                        }
089                        boolean exposeProxy = Boolean.parseBoolean(sourceElement.getAttribute(EXPOSE_PROXY_ATTRIBUTE));
090                        if (exposeProxy) {
091                                AopConfigUtils.forceAutoProxyCreatorToExposeProxy(registry);
092                        }
093                }
094        }
095
096        private static void registerComponentIfNecessary(@Nullable BeanDefinition beanDefinition, ParserContext parserContext) {
097                if (beanDefinition != null) {
098                        parserContext.registerComponent(
099                                        new BeanComponentDefinition(beanDefinition, AopConfigUtils.AUTO_PROXY_CREATOR_BEAN_NAME));
100                }
101        }
102
103}