Spring MVC学习07拦截器

自定义拦截器：

 1 package com.yas.interceptor;
 2 
 3 import org.springframework.web.servlet.HandlerInterceptor;
 4 import org.springframework.web.servlet.ModelAndView;
 5 
 6 import javax.servlet.http.HttpServletRequest;
 7 import javax.servlet.http.HttpServletResponse;
 8 import javax.servlet.http.HttpSession;
 9 
10 public class MyInterceptor implements HandlerInterceptor {
11     //在handler之前执行
12     @Override
13     public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
14 //        System.out.println("preHandle");
15         HttpSession session = request.getSession();
16         if(session.getAttribute("state")!=null){
17             return true;
18         }
19         response.sendRedirect("/login.jsp");
20         return false;
21     }
22 
23     //在handler之后，响应之前执行
24     //改动请求中的数据
25     @Override
26     public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
27 //        System.out.println("postHandle");
28     }
29 
30     //在视图渲染完毕之后执行
31     //资源回收
32     @Override
33     public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
34 //        System.out.println("afterCompletion");
35     }
36 }

定义Controller：

 1 package com.yas.controller;
 2 
 3 import org.springframework.stereotype.Controller;
 4 import org.springframework.ui.Model;
 5 import org.springframework.web.bind.annotation.RequestMapping;
 6 import org.springframework.web.bind.annotation.SessionAttributes;
 7 
 8 @Controller
 9 @RequestMapping("/inter")
10 @SessionAttributes("state")
11 public class InterceptorController {
12 
13     @RequestMapping("/login")
14     public String login(Model model){
15         model.addAttribute("state","ok");
16         return "main";
17     }
18 
19     @RequestMapping("/test1")
20     public String test1(){
21         return "main";
22     }
23 
24     @RequestMapping("/test2")
25     public String test2(){
26         return "main";
27     }
28 }

在mvc.xml进行配置：

<mvc:interceptors>
        <mvc:interceptor>
<!--            <mvc:mapping path="/inter/test1"/>-->
<!--            <mvc:mapping path="/inter/test2"/>-->
            <mvc:mapping path="/inter/**"/>
            <mvc:exclude-mapping path="/inter/login"/>
            <bean class="com.yas.interceptor.MyInterceptor"></bean>
        </mvc:interceptor>
    </mvc:interceptors>