Spring MVC 之拦截器（八）

 在springMVC中实现拦截器有两种方式

1、实现HandlerInterceptor接口

2、继承HandlerInterceptorAdaptor类

编写拦截器：

 package com.cy.springannotation.interceptor;

 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;

 import org.apache.log4j.Logger;
 import org.springframework.web.servlet.HandlerInterceptor;
 import org.springframework.web.servlet.ModelAndView;
 /**
  * 拦截器
  * @author acer
  *
  */
 public class MyIntercetor implements HandlerInterceptor{
     private Logger log=Logger.getLogger(this.getClass());

     @Override
     public void afterCompletion(HttpServletRequest arg0,
             HttpServletResponse arg1, Object arg2, Exception arg3)
             throws Exception {
         log.info("1---afterCompletion方法-----DispatcherServlet完全处理完请求后被调用，往往执行一些资源清理动作");
     }

     @Override
     public void postHandle(HttpServletRequest arg0, HttpServletResponse arg1,
             Object arg2, ModelAndView arg3) throws Exception {
         log.info("1---postHandle方法----------Controller方法后");
     }

     @Override
     public boolean preHandle(HttpServletRequest arg0, HttpServletResponse arg1,
             Object arg2) throws Exception {
         log.info("1---preHandle方法-----------Controller方法前");
         //如返回为false的时候，拦截器可阻止方法的调用 ，默认返回false
 //        return false;
         return true;
     }

 }

在springAnnotation-servlet.xml里配置：

  <!-- 配置拦截器 -->
       <mvc:interceptors>
         <mvc:interceptor>
           <mvc:mapping path="/login.do"/>
           <bean class="com.cy.springannotation.interceptor.MyIntercetor"></bean>
         </mvc:interceptor>
      </mvc:interceptors> 

配置多个拦截器的时候：

 <!-- 配置拦截器 -->
       <mvc:interceptors>
         <mvc:interceptor>
           <mvc:mapping path="/login.do"/>  <!-- 如果不配置mapping则默认所有请求均被该拦截器拦截 -->
           <bean class="com.cy.springannotation.interceptor.MyIntercetor"></bean>
         </mvc:interceptor>
         <mvc:interceptor>
           <mvc:mapping path="/*"/>
           <bean class="com.cy.springannotation.interceptor.SecondIntercetor"></bean>
         </mvc:interceptor>
      </mvc:interceptors> 

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