loginfilterservlet.java

学生管理系统

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

package warren.eaststd.jsp.stuinfo;

import java.io.*;
import java.net.*;

import javax.servlet.*;
import javax.servlet.http.*;

/**
 *
 * @author Administrator
 */
public class LoginFilterServlet extends HttpServlet {
   
    /** 
    * Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods.
    * @param request servlet request
    * @param response servlet response
    */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
    
        
        Cookie[] cs = request.getCookies();
        if(cs!=null){
        for(Cookie c:cs){
            String name = c.getName();
            if(name.equals("userName")){
                HttpSession session = request.getSession(true);
                session.setAttribute("userName", c.getValue());
                response.sendRedirect(request.getContextPath()+"/main.jsp");
                return;
            }
        }
        }
        response.sendRedirect(request.getContextPath()+"/login.jsp");
    } 

       /** 
    * Handles the HTTP <code>GET</code> method.
    * @param request servlet request
    * @param response servlet response
    */
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    } 

    /** 
    * Handles the HTTP <code>POST</code> method.
    * @param request servlet request
    * @param response servlet response
    */
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    }

    /** 
    * Returns a short description of the servlet.
    */
    public String getServletInfo() {
        return "Short description";
    }
    // </editor-fold>
}