拦截JSP页面，校验是否已登录详解及实现代码

拦截JSP页面，校验是否已登录

   最近使用struts2做项目，需要拦截JSP以校验是否已经登，但struts2的过滤器链只能过滤action。后来发现在web.xml里可以直接增加javax.servlet.Filter实现类的过滤器，可以过滤JSP。请看代码

Filter实现类

package com.common; 
 
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.HttpServlet; 
import javax.servlet.http.HttpServletRequest; 
import javax.servlet.http.HttpServletResponse; 
 
public class LoginFilter extends HttpServlet implements Filter {  
    
  private static final long serialVersionUID = 1L;  
  
  @Override  
  public void doFilter(ServletRequest request, ServletResponse response,  
      FilterChain chain) throws IOException, ServletException {  
    HttpServletRequest req = (HttpServletRequest)request;  
    HttpServletResponse res = (HttpServletResponse)response;  
    String path = req.getContextPath(); 
    String indexPath = req.getScheme()+"://"+req.getServerName()+":"+req.getServerPort()+path+ "/pages/login.jsp"; 
    if(req.getRequestURI().endsWith("login.jsp")) 
    { 
      chain.doFilter(request, response);  
      return; 
    } 
     
    Object loginuser = req.getSession().getAttribute("loginSession");  
    if(loginuser == null){ 
      res.sendRedirect(indexPath);  
      return;  
    } 
    chain.doFilter(request, response);  
  }  
  
  @Override  
  public void init(FilterConfig arg0) throws ServletException {  
    // TODO Auto-generated method stub   
  }  
  
}  
 

登录方法：

 public String login() 
  { 
    Login login = new Login(); 
       
    //.......校验登录信息 
    ActionContext ctx = ActionContext.getContext(); 
    Map session = ctx.getSession(); 
    session.put("loginSession", login); 
    return "success"; 
  } 

 web.xml配置

  
   setlog  
   com.common.LoginFilter  
  
  
   setlog  
   /pages/home.jsp 
   /pages/channel/* 
   /pages/content/* 
   /pages/product/* 
   /pages/vodtask/* 
 

注意，如果页面上使用了框架，则可能导致session超时后退出到登录页面，此时登录页面显示在框架的某个子页面，解决方法，在登录页面加入如下代码即可。

感谢阅读，希望能帮助到大家，谢谢大家对本站的支持！