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/* * 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.web.context.support; import javax.servlet.ServletConfig; import javax.servlet.ServletContext; import org.springframework.beans.BeansException; import org.springframework.beans.factory.config.BeanPostProcessor; import org.springframework.lang.Nullable; import org.springframework.web.context.ServletConfigAware; import org.springframework.web.context.ServletContextAware; /** * {@link org.springframework.beans.factory.config.BeanPostProcessor} * implementation that passes the ServletContext to beans that implement * the {@link ServletContextAware} interface. * * <p>Web application contexts will automatically register this with their * underlying bean factory. Applications do not use this directly. * * @author Juergen Hoeller * @author Phillip Webb * @since 12.03.2004 * @see org.springframework.web.context.ServletContextAware * @see org.springframework.web.context.support.XmlWebApplicationContext#postProcessBeanFactory */ public class ServletContextAwareProcessor implements BeanPostProcessor { @Nullable private ServletContext servletContext; @Nullable private ServletConfig servletConfig; /** * Create a new ServletContextAwareProcessor without an initial context or config. * When this constructor is used the {@link #getServletContext()} and/or * {@link #getServletConfig()} methods should be overridden. */ protected ServletContextAwareProcessor() { } /** * Create a new ServletContextAwareProcessor for the given context. */ public ServletContextAwareProcessor(ServletContext servletContext) { this(servletContext, null); } /** * Create a new ServletContextAwareProcessor for the given config. */ public ServletContextAwareProcessor(ServletConfig servletConfig) { this(null, servletConfig); } /** * Create a new ServletContextAwareProcessor for the given context and config. */ public ServletContextAwareProcessor(@Nullable ServletContext servletContext, @Nullable ServletConfig servletConfig) { this.servletContext = servletContext; this.servletConfig = servletConfig; } /** * Returns the {@link ServletContext} to be injected or {@code null}. This method * can be overridden by subclasses when a context is obtained after the post-processor * has been registered. */ @Nullable protected ServletContext getServletContext() { if (this.servletContext == null && getServletConfig() != null) { return getServletConfig().getServletContext(); } return this.servletContext; } /** * Returns the {@link ServletConfig} to be injected or {@code null}. This method * can be overridden by subclasses when a context is obtained after the post-processor * has been registered. */ @Nullable protected ServletConfig getServletConfig() { return this.servletConfig; } @Override public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException { if (getServletContext() != null && bean instanceof ServletContextAware) { ((ServletContextAware) bean).setServletContext(getServletContext()); } if (getServletConfig() != null && bean instanceof ServletConfigAware) { ((ServletConfigAware) bean).setServletConfig(getServletConfig()); } return bean; } @Override public Object postProcessAfterInitialization(Object bean, String beanName) { return bean; } }