0027SpringMVC拦截器的编写和配置

SpringMvc中想使用拦截器，主要分为两步：

a、编写拦截器，需实现HandlerInterceptor接口

b、springmvc.xml中配置拦截器

逻辑图如下：

 

 

 测试过程主要分为如下几步：

1、编写interceptorIndex.jsp

2、编写InterceptorController.java

3、编写interceptorSuccess.jsp

4、编写拦截器MyInterceptor1.java

5、springmvc.xml中配置拦截器

具体实现如下：

1、编写interceptorIndex.jsp

<%--
  Created by IntelliJ IDEA.
  User: Administrator
  Date: 2019/12/8
  Time: 17:36
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>


    


    
SpringMVC Interceptor测试
    interceptor

2、编写InterceptorController.java

package com.example.controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller
@RequestMapping("/interceptor")
public class InterceptorController {
    public static final String SUCCESS = "interceptorSuccess";
    @RequestMapping("interceptorTest")
    public String interceptorTest(){
        System.out.println("执行controller中的方法");
        return SUCCESS;
    }
}

3、编写interceptorSuccess.jsp

<%--
  Created by IntelliJ IDEA.
  User: Administrator
  Date: 2019/12/8
  Time: 17:43
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>


    


    
执行成功
    <%System.out.println("执行interceptorSuccess.jsp"); %>

4、编写拦截器MyInterceptor1.java

package com.example.interceptor;

import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

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

public class MyInterceptor1 implements HandlerInterceptor {
    @Override
    /*1、返回true代表放行，可以处理后续的拦截器或者controller中的方法
    * 2、返回false代表后续的内容不会被执行，可用参数中的request或者response跳转到错误页面或者登录页面等（权限验证）*/
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        System.out.println("执行MyInterceptor1的前置方法");
        return true;
    }

    @Override
    /*结果页面执行完之后执行*/
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        System.out.println("执行MyInterceptor1的后置方法");
    }

    @Override
　　

/*也可使用参数的request或者response跳转到某些页面，则controller中的return不会被执行，因此可以控制不会跳两个页面*/

    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        System.out.println("执行MyInterceptor1的afterCompletion方法");
    }
}

5、springmvc.xml中配置拦截器

       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:c="http://www.springframework.org/schema/c"
       xmlns:cache="http://www.springframework.org/schema/cache"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:jdbc="http://www.springframework.org/schema/jdbc"
       xmlns:jee="http://www.springframework.org/schema/jee"
       xmlns:lang="http://www.springframework.org/schema/lang"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xmlns:p="http://www.springframework.org/schema/p"
       xmlns:task="http://www.springframework.org/schema/task"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:util="http://www.springframework.org/schema/util"
       xsi:schemaLocation="http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-4.3.xsd
      http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.3.xsd
      http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.3.xsd
      http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.3.xsd
      http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.3.xsd
      http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-4.3.xsd
      http://www.springframework.org/schema/cache http://www.springframework.org/schema/cache/spring-cache-4.3.xsd
      http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task-4.3.xsd
      http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
      http://www.springframework.org/schema/lang http://www.springframework.org/schema/lang/spring-lang-4.3.xsd
      http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.3.xsd ">
    
    
    
    
        
        
        
        
    
    
    
        
            
                
            
        
    

    
    
    

    
    
    

    
    
        
    

    
    
        
            
            
            
            
            
            
        
        
            
            
            
            
            
            
        
    

MyInterceptor2.java与MyInterceptor1.java代码基本相同，不重复罗列。

测试：启动项目，在interceptorIndex.jsp点击链接访问controller中的方法，执行结果如下：

 

 结果总结：

1、执行拦截器的前置方法

2、执行controller中的方法

3、执行拦截器的后置方法

4、执行controller中的return，进入相应的页面，执行页面中的代码

5、页面执行完之后，执行拦截的afterCompletion方法。

 

若有理解不到之处，望指正！