springMVC拦截器和过滤器总结

拦截器： 用来对访问的url进行拦截处理

用处： 权限验证，乱码设置等

spring-mvc.xml文件中的配置：

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:p="http://www.springframework.org/schema/p"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
              xsi:schemaLocation="http://www.springframework.org/schema/beans
                        http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
                        http://www.springframework.org/schema/context
                        http://www.springframework.org/schema/context/spring-context-3.1.xsd
                        http://www.springframework.org/schema/mvc
                        http://www.springframework.org/schema/mvc/spring-mvc-3.1.xsd
                        http://www.springframework.org/schema/tx
                        ">

<!--编写拦截器-->
<mvc:interceptors>
    <!--对特定的url拦截-->
    <mvc:interceptor>
         <mvc:mapping path="/test.do"/>
         <bean class="com.hbut.interceptor.TestInterceptor"/>
    </mvc:interceptor>
    <mvc:interceptor>
          <!--对特定的模块拦截第一级别拦截-->
          <mvc:mapping path="/test/×/"/>
          <bean class="com.hbut.interceptor.TestInterceptor1"/>
     </mvc:interceptor>         
　　　<mvc:interceptor>
          <!--对特定的模块拦截-->
          <mvc:mapping path="/test/×"/>
          <bean class="com.hbut.interceptor.TestInterceptor2"/>
     </mvc:interceptor> 
</mvc:interceptors>

对所有的url进行拦截

<mvc:interceptors>
    <bean class="org.springframework.web.servlet.i18n.LocaleChangeInterceptor"/>
</mvc:interceptors>

java代码

package com.hbut.interceptor;

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

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

/**
 * @Author XiJun.Gong
 * @DATE 2016/6/1.
 * aim:   com.hbut.interceptor
 */
public class TestInterceptor implements HandlerInterceptor {

    @Override
    public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o) throws Exception {
             //todo 在此处添加要操作code        System.out.println("preHandle"); 
        return true;  //todo 此处为false时，请求不会到达control层
    }

    @Override
    public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {
        System.out.println("postHandle");  //todo 可以用来修改信息，跳转等
    }

    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {
        System.out.println("afterCompletion"); //todo 最后执行
    }
}

另一种拦截器：大同小异

package com.hbut.interceptor;

import org.springframework.ui.ModelMap;
import org.springframework.web.context.request.WebRequest;
import org.springframework.web.context.request.WebRequestInterceptor;

/**
 * @Author XiJun.Gong
 * @DATE 2016/6/1.
 * aim:   com.hbut.interceptor
 */
public class Test2Interceptor implements WebRequestInterceptor {
    @Override
    public void preHandle(WebRequest webRequest) throws Exception {
    }

    @Override
    public void postHandle(WebRequest webRequest, ModelMap modelMap) throws Exception {

    }

    @Override
    public void afterCompletion(WebRequest webRequest, Exception e) throws Exception {

    }
}

过滤器： 依赖于servlet容器，使用回调函数，过滤范围大

拦截器： 依赖于框架容器 比如spring、mybatis ，灵活