cookie保存user数据及cookie实现自动登录

来源：互联网发布：无锡知原药业有限公司编辑：程序博客网时间：2024/05/22 02:46

1.login.jsp

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%><%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html>  <head>    <base href="<%=basePath%>">        <title>My JSP 'login.jsp' starting page</title>    <meta http-equiv="pragma" content="no-cache"><meta http-equiv="cache-control" content="no-cache"><meta http-equiv="expires" content="0">    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"><meta http-equiv="description" content="This is my page"><!--<link rel="stylesheet" type="text/css" href="styles.css">-->  </head>    <body>  <%  //拿到客户端的cookies文件  Cookie[] cookies=request.getCookies();  //若cookies不为空，，循环去数据  if(cookies != null)  {    for(Cookie c: cookies)  {   //若有name为"autoLogin"的cookies,,直接跳转到主页面  if(c.getName().equals("autoLogin"))  {     request.getRequestDispatcher("index.jsp").forward(request,response);  }  }    }   %><!-- 否则显示登录页面 -->             <form method="post" action="servlet/LoginServlet">               <table align="center">                 <tr><td>账户：</td><td><input type="text" name="user"></td></tr>                 <tr><td>密码：</td><td><input type="password" name="pwd"></td></tr>                 <tr ><td><input type="checkbox" name="autologin">自动登录</td></tr>                 <tr><td><input type="submit" value="提交"></td><td><input type="reset" value="取消"></td></tr>                 <tr><td></td></tr>               </table>             </form>      </body></html>

2，LoginServlet

package com.servlet;import java.io.IOException;import java.io.PrintWriter;import java.net.URLEncoder;import java.util.Iterator;import javax.servlet.ServletException;import javax.servlet.http.Cookie;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class LoginServlet extends HttpServlet {public LoginServlet() {super();}public void destroy() {super.destroy(); // Just puts "destroy" string in log}public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {this.doPost(request, response);}public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {        String user = request.getParameter("user");        System.out.println(user);        //设置user的cookie,完整页面间共享，替代session                //中文保存数据  encode保存进去 decode出来         user = URLEncoder.encode(user,"utf-8");                Cookie cookieUser = new Cookie("user", user);        cookieUser.setMaxAge(20*60000);        cookieUser.setPath("/");        //将cookie添加到http首部里去        response.addCookie(cookieUser);        //判断是否自动登录，        String autoLogin = request.getParameter("autologin");              if(autoLogin != null)        {              Cookie autoLoginCookie=new Cookie("autoLogin","auto");        autoLoginCookie.setMaxAge(20*60000);        autoLoginCookie.setPath("/");        response.addCookie(autoLoginCookie);        }              response.sendRedirect(request.getContextPath()+"/index.jsp");}public void init() throws ServletException {}}

3，index.jsp

<%@ page language="java"  import="java.util.*,java.net.URLDecoder,com.servlet.*" pageEncoding="utf-8"%><%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%><<style>.d1{font-size:xx-large;font-weight: 300;font-style:italic;color: red; }</style><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html>  <head>    <base href="<%=basePath%>">        <title>My JSP 'index.jsp' starting page</title><meta http-equiv="pragma" content="no-cache"><meta http-equiv="cache-control" content="no-cache"><meta http-equiv="expires" content="0">    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"><meta http-equiv="description" content="This is my page"><!--<link rel="stylesheet" type="text/css" href="styles.css">-->  </head>    <body>    <%     //从客户端取出存入的cookie用户信息    String user=" ";    Cookie[] cookies = request.getCookies();    for (int i = 0; i < cookies.length; i++)     {if(cookies[i].getName().equals("user")){user=cookies[i].getValue();user=URLDecoder.decode(user, "utf-8");%><div align="center" class="d1"> 欢迎<%=user%>登录！！</div><%    }    }    %>    <div align="center">          </div>  </body></html>