spring之拦截器

拦截器

实现HandlerInterceptor接口：注册拦截器<mvc:inteceptors>

spring和springMVC父子容器的关系

     在spring整体框架的核心概念中，容器是核心思想，就是用来管理Bean的整个生命周期的，而在一个项目中，容器不一定只有一个，spring中可以包括多个容器，而且容器有上下层关系，目前最常见的一种场景就是在项目中引入spring和springmvc两个框架，那么它其实就是两个容器，spring是父容器，springmvc是子容器，并且在spring父容器中注册的bean对于springmvc容器中是可见的，而在springmvc容器中注册的bean对于spring父容器中就是不可见的，也就是子容器可以看见父容器中注册的Bean，反之就不行。

 全部拦截：

 1 <%@ page language="java" contentType="text/html; charset=UTF-8"
 2     pageEncoding="UTF-8"%>
 3 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
 4 <html>
 5 <head>
 6 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 7 <title>Insert title here</title>
 8 </head>
 9 <body>
10            <form action="${pageContext.request.contextPath }/springmvc/hello" method="post">
11          姓名：<input type="text" name="username"><br>            
12       年龄：<input type="text" name="age"><br>
13       <input type="submit" value="提交">
14            </form>
15 </body>
16 </html>
 1 package com.bjsxt.handlers;
 2 
 3 import java.util.Map;
 4 
 5 import org.springframework.context.annotation.Scope;
 6 import org.springframework.stereotype.Controller;
 7 import org.springframework.ui.Model;
 8 import org.springframework.ui.ModelMap;
 9 import org.springframework.web.bind.annotation.RequestMapping;
10 
11 //后台控制器
12 @Controller
13 @Scope("prototype")
14 @RequestMapping("/springmvc")
15 public class MyController{
16 //接收json字符串封装成对象
17 @RequestMapping("/hello")
18 public String hello1(String username,int age,Model model,Map<String,Object>map,ModelMap modelMap){
19     System.out.println(username+"______"+age);
20     model.addAttribute("username", username);
21     System.out.println("MyController.hello1()");
22     map.put("age", age);
23     modelMap.addAttribute("gender", "female");
24     System.out.println("MyController.hello1()");
25     return "welcome";
26     
27 }
28     
29 }
 1 package com.bjsxt.interceptors;
 2 
 3 import javax.servlet.http.HttpServletRequest;
 4 import javax.servlet.http.HttpServletResponse;
 5 
 6 import org.springframework.web.servlet.HandlerInterceptor;
 7 import org.springframework.web.servlet.ModelAndView;
 8 //自定义拦截器
 9 public class FistInterceptor implements HandlerInterceptor {
10     //该方法执行时机：处理器方法执行之前
11         @Override
12         public boolean preHandle(HttpServletRequest request, HttpServletResponse response,
13                 Object handler) throws Exception {
14             System.out.println("拦截器执行");
15             return false;
16         }
17 
18     //该方法执行时机：所有方法处理完成执行之后，响应给浏览器客户端执行
19     @Override
20     public void afterCompletion(HttpServletRequest arg0,
21             HttpServletResponse arg1, Object arg2, Exception arg3)
22             throws Exception {
23         // TODO Auto-generated method stub
24 
25     }
26 
27     //该方法执行时机：处理器方法执行之后
28     @Override
29     public void postHandle(HttpServletRequest arg0, HttpServletResponse arg1,
30             Object arg2, ModelAndView arg3) throws Exception {
31         // TODO Auto-generated method stub
32 
33     }
34 
35 }
<?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:context="http://www.springframework.org/schema/context" 
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xmlns:aop="http://www.springframework.org/schema/aop"
    xsi:schemaLocation="
        http://www.springframework.org/schema/beans 
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/tx 
        http://www.springframework.org/schema/tx/spring-tx.xsd
        http://www.springframework.org/schema/aop 
        http://www.springframework.org/schema/aop/spring-aop.xsd
        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc.xsd
        http://www.springframework.org/schema/context 
        http://www.springframework.org/schema/context/spring-context.xsd">
    <!-- 注册组件扫描器 -->
    <context:component-scan base-package="com.bjsxt.handlers"></context:component-scan>
    <!-- 注册注解驱动 -->
    <mvc:annotation-driven/>
    <!-- 注册视图解析器 -->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/jsp/"></property>
        <property name="suffix" value=".jsp"></property>
    </bean>
        <!-- 注册拦截器 -->
        <mvc:interceptors>
            <mvc:interceptor>
                <mvc:mapping path="/**"/>
                <bean id="" class="com.bjsxt.interceptors.FistInterceptor"></bean>
            </mvc:interceptor>
        </mvc:interceptors>
    <!-- 静态资源无法访问第二种解决方案 -->
    <!-- <mvc:default-servlet-handler/> -->
    <!-- 静态资源无法访问第三种解决方案 -->
    <mvc:resources location="/images/" mapping="/images/**"></mvc:resources>
    <mvc:resources location="/js/" mapping="/js/**"></mvc:resources>
</beans>
 1 <%@ page language="java" contentType="text/html; charset=UTF-8"
 2     pageEncoding="UTF-8"%>
 3 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
 4 <html>
 5 <head>
 6 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 7 <title>Insert title here</title>
 8 </head>
 9 <body>
10     欢迎页面！${username}--${age}--${gender}
11 </body>
12 </html>

 指定拦截

 1 <%@ page language="java" contentType="text/html; charset=UTF-8"
 2     pageEncoding="UTF-8"%>
 3 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
 4 <html>
 5 <head>
 6 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 7 <title>Insert title here</title>
 8 </head>
 9 <body>
10     <form action="${pageContext.request.contextPath}/springmvc/hello2" method="POST">
11         姓名：<input type="text" name="username"><br/>
12         年龄：<input type="text" name="age"><br/>
13         <input type="submit" value="提交"><br/>
14     </form>
15 </body>
16 </html>
 1 package com.bjsxt.handlers;
 2 
 3 import java.util.Map;
 4 
 5 import org.springframework.context.annotation.Scope;
 6 import org.springframework.stereotype.Controller;
 7 import org.springframework.ui.Model;
 8 import org.springframework.ui.ModelMap;
 9 import org.springframework.web.bind.annotation.RequestHeader;
10 import org.springframework.web.bind.annotation.RequestMapping;
11 
12 //后端控制器
13 @Controller 
14 @Scope("prototype")
15 @RequestMapping("/springmvc")  
16 public class MyController{
17     @RequestMapping("/hello")
18     public String  hello1(String username,int age,Model model,Map<String, Object> map,ModelMap modelMap){
19         System.out.println(username + " ----------"+age);
20         model.addAttribute("username", username);
21         map.put("age", age);
22         modelMap.addAttribute("gender", "female");
23         return "welcome";
24     }
25     @RequestMapping("/hello2")
26     public String  hello2(String username,int age,Model model,Map<String, Object> map,ModelMap modelMap){
27         System.out.println(username + " 2222----------2222"+age);
28         model.addAttribute("username", username);
29         map.put("age", age);
30         modelMap.addAttribute("gender", "female");
31         return "welcome";
32     }
33 
34 }
 1 package com.bjsxt.interceptors;
 2 
 3 import javax.servlet.http.HttpServletRequest;
 4 import javax.servlet.http.HttpServletResponse;
 5 
 6 import org.springframework.web.servlet.HandlerInterceptor;
 7 import org.springframework.web.servlet.ModelAndView;
 8 
 9 //自定义拦截器
10 public class FirstInterceptor implements HandlerInterceptor {
11     //该方法执行时机：处理器方法执行之前执行
12     @Override
13     public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
14             throws Exception {
15         System.out.println("拦截器preHandle（）执行！");
16         return true;
17     }
18 
19     //该方法执行时机：处理器方法执行之后执行
20     @Override
21     public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
22             ModelAndView modelAndView) throws Exception {
23         System.out.println("拦截器postHandle()执行！");
24 
25     }
26     
27     //该方法执行时机：所有工作处理完成之后，响应给浏览器客户端之前执行
28     @Override
29     public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
30             throws Exception {
31         System.out.println("拦截器afterCompletion()执行！");
32 
33     }
34 
35 }
 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <beans xmlns="http://www.springframework.org/schema/beans"
 3     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 4     xmlns:context="http://www.springframework.org/schema/context" 
 5     xmlns:mvc="http://www.springframework.org/schema/mvc"
 6     xmlns:tx="http://www.springframework.org/schema/tx"
 7     xmlns:aop="http://www.springframework.org/schema/aop"
 8     xsi:schemaLocation="
 9         http://www.springframework.org/schema/beans 
10         http://www.springframework.org/schema/beans/spring-beans.xsd
11         http://www.springframework.org/schema/tx 
12         http://www.springframework.org/schema/tx/spring-tx.xsd
13         http://www.springframework.org/schema/aop 
14         http://www.springframework.org/schema/aop/spring-aop.xsd
15         http://www.springframework.org/schema/mvc
16         http://www.springframework.org/schema/mvc/spring-mvc.xsd
17         http://www.springframework.org/schema/context 
18         http://www.springframework.org/schema/context/spring-context.xsd">
19     <!-- 注册组件扫描器 -->
20     <context:component-scan base-package="com.bjsxt.handlers"></context:component-scan>
21     <!-- 注册注解驱动 -->
22     <mvc:annotation-driven/>
23     <!-- 注册视图解析器 -->
24     <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
25         <property name="prefix" value="/jsp/"></property>
26         <property name="suffix" value=".jsp"></property>
27     </bean>
28     
29     <!-- 注册拦截器 -->
30     <mvc:interceptors>
31         <mvc:interceptor>
32             <mvc:mapping path="/springmvc/hello"/>
33             <mvc:mapping path="/**"/>
34             <mvc:exclude-mapping path="/springmvc/hello2"/>
35             <bean id="" class="com.bjsxt.interceptors.FirstInterceptor"></bean>
36         </mvc:interceptor>
37     </mvc:interceptors>
38         
39     <!-- 静态资源无法访问第二种解决方案 -->
40     <!-- <mvc:default-servlet-handler/> -->
41     <!-- 静态资源无法访问第三种解决方案 -->
42     <mvc:resources location="/images/" mapping="/images/**"></mvc:resources>
43     <mvc:resources location="/js/" mapping="/js/**"></mvc:resources>
44 </beans>
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原文地址：https://www.cnblogs.com/wq-9/p/10198583.html