001/*
002 * Copyright 2002-2017 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.scope;
018
019import org.springframework.aop.framework.autoproxy.AutoProxyUtils;
020import org.springframework.beans.factory.config.BeanDefinition;
021import org.springframework.beans.factory.config.BeanDefinitionHolder;
022import org.springframework.beans.factory.support.AbstractBeanDefinition;
023import org.springframework.beans.factory.support.BeanDefinitionRegistry;
024import org.springframework.beans.factory.support.RootBeanDefinition;
025
026/**
027 * Utility class for creating a scoped proxy.
028 * Used by ScopedProxyBeanDefinitionDecorator and ClassPathBeanDefinitionScanner.
029 *
030 * @author Mark Fisher
031 * @author Juergen Hoeller
032 * @author Rob Harrop
033 * @since 2.5
034 */
035public abstract class ScopedProxyUtils {
036
037        private static final String TARGET_NAME_PREFIX = "scopedTarget.";
038
039
040        /**
041         * Generate a scoped proxy for the supplied target bean, registering the target
042         * bean with an internal name and setting 'targetBeanName' on the scoped proxy.
043         * @param definition the original bean definition
044         * @param registry the bean definition registry
045         * @param proxyTargetClass whether to create a target class proxy
046         * @return the scoped proxy definition
047         */
048        public static BeanDefinitionHolder createScopedProxy(BeanDefinitionHolder definition,
049                        BeanDefinitionRegistry registry, boolean proxyTargetClass) {
050
051                String originalBeanName = definition.getBeanName();
052                BeanDefinition targetDefinition = definition.getBeanDefinition();
053                String targetBeanName = getTargetBeanName(originalBeanName);
054
055                // Create a scoped proxy definition for the original bean name,
056                // "hiding" the target bean in an internal target definition.
057                RootBeanDefinition proxyDefinition = new RootBeanDefinition(ScopedProxyFactoryBean.class);
058                proxyDefinition.setDecoratedDefinition(new BeanDefinitionHolder(targetDefinition, targetBeanName));
059                proxyDefinition.setOriginatingBeanDefinition(targetDefinition);
060                proxyDefinition.setSource(definition.getSource());
061                proxyDefinition.setRole(targetDefinition.getRole());
062
063                proxyDefinition.getPropertyValues().add("targetBeanName", targetBeanName);
064                if (proxyTargetClass) {
065                        targetDefinition.setAttribute(AutoProxyUtils.PRESERVE_TARGET_CLASS_ATTRIBUTE, Boolean.TRUE);
066                        // ScopedProxyFactoryBean's "proxyTargetClass" default is TRUE, so we don't need to set it explicitly here.
067                }
068                else {
069                        proxyDefinition.getPropertyValues().add("proxyTargetClass", Boolean.FALSE);
070                }
071
072                // Copy autowire settings from original bean definition.
073                proxyDefinition.setAutowireCandidate(targetDefinition.isAutowireCandidate());
074                proxyDefinition.setPrimary(targetDefinition.isPrimary());
075                if (targetDefinition instanceof AbstractBeanDefinition) {
076                        proxyDefinition.copyQualifiersFrom((AbstractBeanDefinition) targetDefinition);
077                }
078
079                // The target bean should be ignored in favor of the scoped proxy.
080                targetDefinition.setAutowireCandidate(false);
081                targetDefinition.setPrimary(false);
082
083                // Register the target bean as separate bean in the factory.
084                registry.registerBeanDefinition(targetBeanName, targetDefinition);
085
086                // Return the scoped proxy definition as primary bean definition
087                // (potentially an inner bean).
088                return new BeanDefinitionHolder(proxyDefinition, originalBeanName, definition.getAliases());
089        }
090
091        /**
092         * Generate the bean name that is used within the scoped proxy to reference the target bean.
093         * @param originalBeanName the original name of bean
094         * @return the generated bean to be used to reference the target bean
095         */
096        public static String getTargetBeanName(String originalBeanName) {
097                return TARGET_NAME_PREFIX + originalBeanName;
098        }
099
100        /**
101         * Specify if the {@code beanName} is the name of a bean that references the target
102         * bean within a scoped proxy.
103         * @since 4.1.4
104         */
105        public static boolean isScopedTarget(String beanName) {
106                return (beanName != null && beanName.startsWith(TARGET_NAME_PREFIX));
107        }
108
109}