SpringMVC拦截器实现监听session是否过期详解

本文主要向大家介绍了SpringMVC 拦截器实现：当用户访问网站资源时，监听 session是否过期的代码，具体如下：

一、拦截器配置

									<mvc:interceptors>

									  <mvc:interceptor>

									    <mvc:mapping path="/**"/>

									    <mvc:exclude-mapping path="/user/login"/>  <!-- 不拦截登录请求 -->

									    <mvc:exclude-mapping path="/user/logout"/>  <!-- 不拦截注销请求 -->

									    <mvc:exclude-mapping path="*.jsp"/>

									    <mvc:exclude-mapping path="*.html"/>

									    <mvc:exclude-mapping path="*.js"/>

									    <mvc:exclude-mapping path="*.css"/>

									    <bean class="org.huaxin.interceptor.AccessInterceptor"></bean>

									  </mvc:interceptor>

									</mvc:interceptors>

二、拦截器编码

									public boolean preHandle(HttpServletRequest request, HttpServletResponse response,

									      Object obj) throws Exception {

									    System.out.println("[AccessInterceptor]:preHandle执行");

									    HttpSession session = request.getSession();

									    ServletContext application = session.getServletContext();

									    if(application.getAttribute(session.getId()) == null){  //未登录

									      PrintWriter out = response.getWriter();

									      StringBuffer sb = new StringBuffer("<script type=\"text/javascript\" charset=\"UTF-8\">");

									      sb.append("alert(\"你的账号被挤掉，或者没有登录，或者页面已经过期，请重新登录\")");

									      sb.append("window.location.href='/user/logout';");

									      sb.append("</script>");

									      out.print(sb.toString());

									      out.close();

									      return false;

									    }else{  //已经登录

									      return true;

									    }

									  }