spring攔截器(interceptor)簡介

1. 攔截器用途

　　（1）攔截未登錄用戶直接訪問某些鏈接

　　（2）攔截日志信息

　　（3）攔截非法攻擊，比如sql注入

2. 涉及jar、類

　　（1）spring-webmvc.jar

　　（2）HandlerInterceptor(org.springframework.web.servlet：接口)、

　　　　  AsyncHandlerInterceptor(org.springframework.web.servlet：接口)、　

　　　　  HandlerInterceptorAdapter(org.springframework.web.servlet.handler.HandlerInterceptorAdapter：抽象類)

3.業務類

　　（1）實現（implements） 實現HandlerInterceptor接口或者子接口

　　（2）繼承（extends） 繼承HandlerInterceptor接口子類（抽象類）

　　（3）涉及的方法

　　　　  preHandle、postHandle、afterCompletion

4.測試代碼

LoginInterceptor

public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler throws Exception {
　　LOGGER.info("--------preHandle-------" + request.getRequestURI());
　　HttpSession session = request.getSession();
　　String login_account = String.valueOf(session.getAttribute(CommonConstants.SESSION_KEY+session.getId()));
　　if(!request.getRequestURI().contains("/baselogin/")){
　　　　if (StringUtils.isBlank(login_account) || "null".equalsIgnoreCase(login_account)) {
　　　　　　response.sendRedirect("/baselogin/loginPage.htm");
　　　　　　return false;
 9 　　　　}
　　}
　　return true;
}

public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView)throws Exception {
　　LOGGER.info("--------postHandle-------" + request.getRequestURI());
}

public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
　　LOGGER.info("--------afterCompletion-------" + request.getRequestURI());
}

public void afterConcurrentHandlingStarted(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
23 　　LOGGER.info("--------afterConcurrentHandlingStarted-------" + request.getRequestURI());
}

執行順序：preHandle -> controller -> postHandle -> afterCompletion

配置：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:p="http://www.springframework.org/schema/p" xmlns:mvc="http://www.springframework.org/schema/mvc"
    xsi:schemaLocation="http://www.springframework.org/schema/context  
    http://www.springframework.org/schema/context/spring-context-3.2.xsd
    http://www.springframework.org/schema/beans  
    http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
    http://www.springframework.org/schema/aop 
    http://www.springframework.org/schema/aop/spring-aop-3.2.xsd
    http://www.springframework.org/schema/mvc
    http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd
    ">
<!-- 攔截排除
<mvc:interceptors>

        <mvc:interceptor>

　　　　　　<mvc:exclude-mapping path=""/>

　　　　　　<bean class="org.bighead.interceptor.LoginInterceptor" />
 　　　　</mvc:interceptor>
 </mvc:interceptors>

-->

<!-- 攔截登錄 -->
    <mvc:interceptors>
        <mvc:interceptor>
            <mvc:mapping path="/*/*.htm"/>
            <bean class="org.bighead.interceptor.LoginInterceptor" />
        </mvc:interceptor>
    </mvc:interceptors>
<beans>