JSP的Cookie在登录中的使用方法

2024-09-05 00:18:32

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cookie是浏览器访问某些网站后存储在客户端的一组数据，用于使网站跟踪用户，实现用户自定义功能，那么JSP的Cookie在登录中的使用方法大家了解多少呢？别着急，错新技术频道小编为你细细道来。

JSP的Cookie在登录中的使用

一功能需求

实现记忆用户名和密码功能。

二代码

1、login.jsp

<%@ page language="java" import="java.util.*,java.net.*" contentType="text/html; charset=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%>" rel="external nofollow" rel="external nofollow" rel="external nofollow" >    <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" rel="external nofollow" rel="external nofollow" rel="external nofollow" >    --> </head>  <body>  <h1>用户登录</h1>  <hr>  <%   request.setCharacterEncoding("utf-8");   String username="";   String password = "";   Cookie[] cookies = request.getCookies();   if(cookies!=null&&cookies.length>0)   {      for(Cookie c:cookies)      {       if(c.getName().equals("username"))       {          username = URLDecoder.decode(c.getValue(),"utf-8");       }       if(c.getName().equals("password"))       {          password = URLDecoder.decode(c.getValue(),"utf-8");       }      }   }  %>  <form name="loginForm" action="dologin.jsp" method="post">    <table>     <tr>      <td>用户名：</td>      <td><input type="text" name="username" value="<%=username %>"/></td>     </tr>     <tr>      <td>密码：</td>      <td><input type="password" name="password" value="<%=password %>" /></td>     </tr>     <tr>      <td colspan="2"><input type="checkbox" name="isUseCookie" checked="checked"/>十天内记住我的登录状态</td>     </tr>     <tr>      <td colspan="2" align="center"><input type="submit" value="登录"/><input type="reset" value="取消"/></td>     </tr>    </table>  </form> </body></html>

2、dologin.jsp

<%@ page language="java" import="java.util.*,java.net.*" contentType="text/html; charset=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%>" rel="external nofollow" rel="external nofollow" rel="external nofollow" >    <title>My JSP 'dologin.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" rel="external nofollow" rel="external nofollow" rel="external nofollow" >    -->  </head>  <body>  <h1>登录成功</h1>  <hr>  <br>  <br>  <br>  <%    request.setCharacterEncoding("utf-8");    //首先判断用户是否选择了记住登录状态    String[] isUseCookies = request.getParameterValues("isUseCookie");    if(isUseCookies!=null&&isUseCookies.length>0)    {     //把用户名和密码保存在Cookie对象里面     String username = URLEncoder.encode(request.getParameter("username"),"utf-8");     //使用URLEncoder解决无法在Cookie当中保存中文字符串问题     String password = URLEncoder.encode(request.getParameter("password"),"utf-8");          Cookie usernameCookie = new Cookie("username",username);     Cookie passwordCookie = new Cookie("password",password);     usernameCookie.setMaxAge(864000);     passwordCookie.setMaxAge(864000);//设置最大生存期限为10天     response.addCookie(usernameCookie);     response.addCookie(passwordCookie);    }    else    {     Cookie[] cookies = request.getCookies();     if(cookies!=null&&cookies.length>0)     {       for(Cookie c:cookies)       {        if(c.getName().equals("username")||c.getName().equals("password"))        {          c.setMaxAge(0); //设置Cookie失效          response.addCookie(c); //重新保存。        }       }     }    }  %>  <a href="users.jsp" rel="external nofollow" target="_blank">查看用户信息</a>   </body> </html>

3、users.jsp

<%@ page language="java" import="java.util.*,java.net.*" contentType="text/html; charset=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%>" rel="external nofollow" rel="external nofollow" rel="external nofollow" >    <title>My JSP 'users.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" rel="external nofollow" rel="external nofollow" rel="external nofollow" >    -->  </head>  <body>  <h1>用户信息</h1>  <hr>  <%   request.setCharacterEncoding("utf-8");   String username="";   String password = "";   Cookie[] cookies = request.getCookies();   if(cookies!=null&&cookies.length>0)   {      for(Cookie c:cookies)      {       if(c.getName().equals("username"))       {          username = URLDecoder.decode(c.getValue(),"utf-8");       }       if(c.getName().equals("password"))       {          password = URLDecoder.decode(c.getValue(),"utf-8");       }      }   }  %>  <BR>  <BR>  <BR>     用户名：<%=username %><br>     密码：<%=password %><br> </body></html>

三测试