springMVC的拦截器

1.创建一个类实现HandlerInterceptor接口，并重写接口里的方法

package com.zhiyou100.kfs.interceptor;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.springframework.web.servlet.HandlerInterceptor;

import org.springframework.web.servlet.ModelAndView;

public class LoginInterceptor implements HandlerInterceptor {

       @Override

       public void afterCompletion(HttpServletRequest arg0, HttpServletResponse arg1, Object arg2, Exception arg3)

                     throws Exception {

              System.out.println("在请求执行完后执行，资源关闭");

       }

       @Override

       public void postHandle(HttpServletRequest arg0, HttpServletResponse arg1, Object arg2, ModelAndView arg3)

                     throws Exception {

              System.out.println("在请求处理完后");

             

       }

       @Override

       public boolean preHandle(HttpServletRequest arg0, HttpServletResponse arg1, Object arg2) throws Exception {

              System.out.println("在Controller前");

              return true;//返回true放行，若返回false则不放行

       }

}

2.在springMVC配置拦截器

       <!-- 配置拦截器 -->

       <mvc:interceptors>

              <mvc:interceptor>

                     <mvc:mapping path="/user/**"/><!-- 拦截的请求路径，**：表示user下的请求地址以及子目录 -->

                     <mvc:exclude-mapping path="/user/register"/><!-- 不拦截的请求路径 -->

                     <bean class="com.zhiyou100.kfs.interceptor.LoginInterceptor"></bean>

              </mvc:interceptor>

       </mvc:interceptors>