Java tutorial
/* * Copyright 2002-2017 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 * * https://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.aop.scope; import org.springframework.aop.framework.autoproxy.AutoProxyUtils; import org.springframework.beans.factory.config.BeanDefinition; import org.springframework.beans.factory.config.BeanDefinitionHolder; import org.springframework.beans.factory.support.AbstractBeanDefinition; import org.springframework.beans.factory.support.BeanDefinitionRegistry; import org.springframework.beans.factory.support.RootBeanDefinition; import org.springframework.lang.Nullable; /** * Utility class for creating a scoped proxy. * Used by ScopedProxyBeanDefinitionDecorator and ClassPathBeanDefinitionScanner. * * @author Mark Fisher * @author Juergen Hoeller * @author Rob Harrop * @since 2.5 */ public abstract class ScopedProxyUtils { private static final String TARGET_NAME_PREFIX = "scopedTarget."; /** * Generate a scoped proxy for the supplied target bean, registering the target * bean with an internal name and setting 'targetBeanName' on the scoped proxy. * @param definition the original bean definition * @param registry the bean definition registry * @param proxyTargetClass whether to create a target class proxy * @return the scoped proxy definition */ public static BeanDefinitionHolder createScopedProxy(BeanDefinitionHolder definition, BeanDefinitionRegistry registry, boolean proxyTargetClass) { String originalBeanName = definition.getBeanName(); BeanDefinition targetDefinition = definition.getBeanDefinition(); String targetBeanName = getTargetBeanName(originalBeanName); // Create a scoped proxy definition for the original bean name, // "hiding" the target bean in an internal target definition. RootBeanDefinition proxyDefinition = new RootBeanDefinition(ScopedProxyFactoryBean.class); proxyDefinition.setDecoratedDefinition(new BeanDefinitionHolder(targetDefinition, targetBeanName)); proxyDefinition.setOriginatingBeanDefinition(targetDefinition); proxyDefinition.setSource(definition.getSource()); proxyDefinition.setRole(targetDefinition.getRole()); proxyDefinition.getPropertyValues().add("targetBeanName", targetBeanName); if (proxyTargetClass) { targetDefinition.setAttribute(AutoProxyUtils.PRESERVE_TARGET_CLASS_ATTRIBUTE, Boolean.TRUE); // ScopedProxyFactoryBean's "proxyTargetClass" default is TRUE, so we don't need to set it explicitly here. } else { proxyDefinition.getPropertyValues().add("proxyTargetClass", Boolean.FALSE); } // Copy autowire settings from original bean definition. proxyDefinition.setAutowireCandidate(targetDefinition.isAutowireCandidate()); proxyDefinition.setPrimary(targetDefinition.isPrimary()); if (targetDefinition instanceof AbstractBeanDefinition) { proxyDefinition.copyQualifiersFrom((AbstractBeanDefinition) targetDefinition); } // The target bean should be ignored in favor of the scoped proxy. targetDefinition.setAutowireCandidate(false); targetDefinition.setPrimary(false); // Register the target bean as separate bean in the factory. registry.registerBeanDefinition(targetBeanName, targetDefinition); // Return the scoped proxy definition as primary bean definition // (potentially an inner bean). return new BeanDefinitionHolder(proxyDefinition, originalBeanName, definition.getAliases()); } /** * Generate the bean name that is used within the scoped proxy to reference the target bean. * @param originalBeanName the original name of bean * @return the generated bean to be used to reference the target bean */ public static String getTargetBeanName(String originalBeanName) { return TARGET_NAME_PREFIX + originalBeanName; } /** * Specify if the {@code beanName} is the name of a bean that references the target * bean within a scoped proxy. * @since 4.1.4 */ public static boolean isScopedTarget(@Nullable String beanName) { return (beanName != null && beanName.startsWith(TARGET_NAME_PREFIX)); } }