利用Cookie显示用户上一次登录的时间 

 1 package com.yxfyg.servlet;
 2 
 3 import java.io.IOException;
 4 import java.text.SimpleDateFormat;
 5 import java.util.Date;
 6 
 7 import javax.servlet.ServletException;
 8 import javax.servlet.http.Cookie;
 9 import javax.servlet.http.HttpServlet;
10 import javax.servlet.http.HttpServletRequest;
11 import javax.servlet.http.HttpServletResponse;
12 
13 import com.yxfyg.util.CookieUtil;
14 
15 public class LastLoginTime extends HttpServlet{
16 
17     @Override
18     protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
19         String username = req.getParameter("username");
20         String password = req.getParameter("password");
21         resp.setContentType("text/html;charset=UTF-8");
22         
23         if("admin".equals(username)&&"root".equals(password)) {
24             Cookie[] cookies = req.getCookies();
25             Cookie last = CookieUtil.selectCookie(cookies, "last");
26             if(last != null) {
27                 SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yy-MM-dd HH:mm:ss");
28                 String lastTime = simpleDateFormat.format(Long.parseLong(last.getValue()));
29                 resp.getWriter().write("欢迎回来，上次登录时间为"+lastTime);
30                 last.setValue(System.currentTimeMillis()+"");
31                 resp.addCookie(last);
32             }else {
33                 resp.getWriter().write("首次登录");
34                 last = new Cookie("last",System.currentTimeMillis()+"");
35                 last.setMaxAge(60*60*24);
36                 resp.addCookie(last);
37             }
38         }else {
39             resp.getWriter().write("登录失败");
40         }
41     }
42     
43     @Override
44     protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
45         doGet(req, resp);
46     }
47 }
 1 package com.yxfyg.util;
 2 
 3 import javax.servlet.http.Cookie;
 4 
 5 public class CookieUtil {
 6     
 7     public static Cookie selectCookie(Cookie[] cookies , String name) {
 8         if(cookies != null) {
 9             for(Cookie cookie : cookies) {
10                 if(name.equals(cookie.getName())) {
11                     return cookie;
12                 }
13             }
14         }
15         return null;
16     }
17 }

 

posted @ 2020-05-02 17:05  yxfyg  阅读(299)  评论(0)    收藏  举报