GZ/nwyj/.svn/pristine/48/4883d11bd0544463c5834f861d5e576a95c0dd86.svn-base

package com.system.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; 

public class AuthFilter implements Filter 
{
public void destroy() {}

public void doFilter(ServletRequest servletRequest, ServletResponse 
servletResponse,FilterChain filterChain) throws IOException, ServletException 
{
HttpServletRequest request = (HttpServletRequest)servletRequest; 
HttpServletResponse response = (HttpServletResponse)servletResponse;
String currentURL = request.getRequestURI(); 
//取得根目录所对应的绝对路径:
String targetURL = currentURL.substring(currentURL.indexOf("/", 1), currentURL.length()); 
//截取到当前文件名用于比较
HttpSession session = request.getSession(false); 
if (!"/login.html".equals(targetURL)&&!currentURL.contains("jsessionid"))
 {//判断当前页是否是重定向以后的登录页面页面，如果是就不做session的判断，防止出现死循环
 if (session == null || session.getAttribute("User_Name") == null) {
 //*用户登录以后需手动添加session
 System.out.println("request.getContextPath()=" + request.getContextPath());
  response.sendRedirect(request.getContextPath() + "/login.html"); 
 return; }}
  //加入filter链继续向下执行
  filterChain.doFilter(request, response); 
}
  public void init(FilterConfig filterConfig) throws ServletException {}
  }