Spring MVC 拦截器

<?xml version="1.0" encoding="UTF-8"?>   <beans xmlns="http://www.springframework.org/schema/beans"      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"      xmlns:tx="http://www.springframework.org/schema/tx"      xmlns:context="http://www.springframework.org/schema/context"      xmlns:aop="http://www.springframework.org/schema/aop"      xmlns:mvc="http://www.springframework.org/schema/mvc"      xsi:schemaLocation="          http://www.springframework.org/schema/beans          http://www.springframework.org/schema/beans/spring-beans-3.0.xsd          http://www.springframework.org/schema/context          http://www.springframework.org/schema/context/spring-context-3.0.xsd          http://www.springframework.org/schema/tx          http://www.springframework.org/schema/tx/spring-tx-3.0.xsd          http://www.springframework.org/schema/mvc                http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd            http://www.springframework.org/schema/aop          http://www.springframework.org/schema/aop/spring-aop-2.5.xsd"          >                       <mvc:interceptors>            <mvc:interceptor>                <mvc:mapping path="/**"/>    <!--需要拦截的ACTION 如 /deskTop/wxcsmain.do-->            <bean class="com.xx.space.backstage.interceptor.CommonInterceptor" />            </mvc:interceptor>         </mvc:interceptors>            </beans> 

package com.xx.space.backstage.interceptor;       import javax.servlet.http.HttpServletRequest;   import javax.servlet.http.HttpServletResponse;       import org.apache.log4j.Logger;   import org.springframework.web.servlet.ModelAndView;   import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;   import org.springframework.web.servlet.handler.SimpleUrlHandlerMapping;   import org.springframework.web.servlet.mvc.support.ControllerClassNameHandlerMapping;       public class CommonInterceptor extends HandlerInterceptorAdapter {       private Logger log = Logger.getLogger(CommonInterceptor.class);           public CommonInterceptor() {}           /**        * 在业务处理器处理请求之前被调用 如果返回false 从当前的拦截器往回执行所有拦截器的afterCompletion(),再退出拦截器链        *         * 如果返回true 执行下一个拦截器,直到所有的拦截器都执行完毕 再执行被拦截的Controller 然后进入拦截器链,        * 从最后一个拦截器往回执行所有的postHandle() 接着再从最后一个拦截器往回执行所有的afterCompletion()        */      @Override      public boolean preHandle(HttpServletRequest request,               HttpServletResponse response, Object handler) throws Exception {           System.out.println("CommonInterceptor拦截器: preHandle");           return true;       }           // 在业务处理器处理请求执行完成后,生成视图之前执行的动作       @Override      public void postHandle(HttpServletRequest request,               HttpServletResponse response,                Object handler,ModelAndView modelAndView) throws Exception {           System.out.println("CommonInterceptor拦截器: postHandle");           SimpleUrlHandlerMapping dd;           ControllerClassNameHandlerMapping ee;       }           /**        * 在DispatcherServlet完全处理完请求后被调用        *         * 当有拦截器抛出异常时,会从当前拦截器往回执行所有的拦截器的afterCompletion()        */      @Override      public void afterCompletion(HttpServletRequest request,               HttpServletResponse response, Object handler, Exception ex)               throws Exception {           System.out.println("CommonInterceptor拦截器: afterCompletion");       }                   }