一、说明

1、网站系统登录，从安全的角度来考虑，登录会话超时，再次页面会退到登录界面。
2、本文配置如何通过过滤器（Filter）实现会话超时（如30分钟）跳转到登录页面，分LoginFilter.java类和web.xml配置两部分。

二、实现代码

过滤器类LoginFilter.java

  

   

    

     

    
    

     

      package com.sale.filter;
     
    
   

    

     

    
    

     

      import java.io.IOException;  
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      import javax.servlet.Filter;  
     
    
   

    

     

    
    

     

      import javax.servlet.FilterChain;  
     
    
   

    

     

    
    

     

      import javax.servlet.FilterConfig;  
     
    
   

    

     

    
    

     

      import javax.servlet.ServletException;  
     
    
   

    

     

    
    

     

      import javax.servlet.ServletRequest;  
     
    
   

    

     

    
    

     

      import javax.servlet.ServletResponse;  
     
    
   

    

     

    
    

     

      import javax.servlet.http.HttpServletRequest;  
     
    
   

    

     

    
    

     

      import javax.servlet.http.HttpServletResponse;  
     
    
   

    

     

    
    

     

      import javax.servlet.http.HttpSession;  
     
    
   

    

     

    
    

     

      /**
     
    
   

    

     

    
    

     

       * @author 作者:Justin
     
    
   

    

     

    
    

     

       * @version 创建时间：2018年1月25日 上午10:36:23
     
    
   

    

     

    
    

     

       * 类说明
     
    
   

    

     

    
    

     

       */
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      public class LoginFilter implements Filter {  
     
    
   

    

     

    
    

     
	 @Override
     
    
   

    

     

    
    

     
    public void destroy() {  
     
    
   

    

     

    
    

     
        // TODO Auto-generated method stub 
     
    
   

    

     

    
    

     
  
     
    
   

    

     

    
    

     

          }  
     
    
   

    

     

    
    

     
    @Override
     
    
   

    

     

    
    

     
    public void doFilter(ServletRequest req, ServletResponse res, 
     
    
   

    

     

    
    

     

       FilterChain chain) throws IOException, ServletException {  
     
    
   

    

     

    
    

     
  
     
    
   

    

     

    
    

     

              HttpServletRequest httpReq=(HttpServletRequest)req;  
     
    
   

    

     

    
    

     

              HttpServletResponse httpRes=(HttpServletResponse)res;  
     
    
   

    

     

    
    

     

              HttpSession httpSession=httpReq.getSession();  
     
    
   

    

     

    
    

     

              String path = httpReq.getRequestURI();	//当前请求相对url
     
    
   

    

     

    
    

     

              String loginUrl = httpReq.getContextPath()+ "/loginout.action";	//1.登录界面url
     
    
   

    

     

    
    

     

              String initUrl = httpReq.getContextPath()+   "/tevo_loginInit.action";	//2.初始化界面url
     
    
   

    

     

    
    

     

              String userName = (String)httpSession.getAttribute("currentUsername");	//在session中获取当前用户名
     
    
   

    

     

    
    

     
        // 1、登陆页面、初始化页面不过滤
     
    
   

    

     

    
    

     
        if(loginUrl.equals(path) || initUrl.equals(path)) {
     
    
   

    

     

    
    

     

                  chain.doFilter(req, res);
     
    
   

    

     

    
    

     
            return;
     
    
   

    

     

    
    

     

              }
     
    
   

    

     

    
    

     

      //
     
    
   

    

     

    
    

     
        if(userName==null){  
     
    
   

    

     

    
    

     

                  httpRes.sendRedirect(loginUrl);
     
    
   

    

     

    
    

     
            return;
     
    
   

    

     

    
    

     

              }else{  
     
    
   

    

     

    
    

     

                  chain.doFilter(req, res); 
     
    
   

    

     

    
    

     
            return;
     
    
   

    

     

    
    

     

              }  
     
    
   

    

     

    
    

     

          }  
     
    
   

    

     

    
    

     
    @Override
     
    
   

    

     

    
    

     
    public void init(FilterConfig arg0) throws ServletException {  
     
    
   

    

     

    
    

     
        // TODO Auto-generated method stub 
     
    
   

    

     

    
    

     
  
     
    
   

    

     

    
    

     

          }  
     
    
   

    

     

    
    

     
  
     
    
   

    

     

    
    

     

      }  
     
    
  
 

web.xml配置

  

   

    

     

    
    

     

      <?xml version="1.0" encoding="UTF-8"?>
     
    
   

    

     

    
    

     

      <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
  <!-- configure loginFilter -->  
     
    
   

    

     

    
    

     
  <filter>  
     
    
   

    

     

    
    

     
     <filter-name>loginFilter</filter-name>  
     
    
   

    

     

    
    

     
     <filter-class>com.sale.filter.LoginFilter</filter-class>  
     
    
   

    

     

    
    

     
  </filter>  
     
    
   

    

     

    
    

     
  <filter-mapping>  
     
    
   

    

     

    
    

     
     <filter-name>loginFilter</filter-name>  
     
    
   

    

     

    
    

     
     <url-pattern>*.action</url-pattern>  
     
    
   

    

     

    
    

     
  </filter-mapping>  
     
    
   

    

     

    
    

     
  <!-- configure session timeout 30 minute -->  
     
    
   

    

     

    
    

     
  <session-config>  
     
    
   

    

     

    
    

     
      <session-timeout>30</session-timeout>  
     
    
   

    

     

    
    

     
  </session-config>  
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      </web-app>
     
    
  
 

文章来源: blog.csdn.net，作者：吾日三省贾斯汀，版权归原作者所有，如需转载，请联系作者。

原文链接：blog.csdn.net/JustinQin/article/details/79178725