package com.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;  
public class MyFilter implements Filter {

	public void destroy() {
		// TODO Auto-generated method stub

	}
    public void doFilter(ServletRequest request, ServletResponse response,  
		            FilterChain Chain) throws IOException, ServletException {  
		        // 过滤用户请求，判断是否登录  
		        HttpServletRequest req = (HttpServletRequest)request;  
		        HttpServletResponse res = (HttpServletResponse)response;  
		 
		          
		        String username = (String)req.getSession().getAttribute("id");  
		          System.out.println(username);
		        if (username == null) {  
		        	request.getRequestDispatcher("/login.jsp").forward(request, response);
		           // String path = httpServletRequest.getContextPath();  
		            //httpServletResponse.sendRedirect(path+"/login.jsp");  
		        }         
		      Chain.doFilter(req, res);  
		    }  
		  
		    
		  
	
	public void init(FilterConfig arg0) throws ServletException {
		// TODO Auto-generated method stub

	}

}