Cookie 获取上次登录时间

Demo04:

package com.test.cookie;

import java.io.IOException;
import java.util.Date;

import javax.servlet.ServletException;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.test.utils.CookieUtils;

/**
 * Servlet implementation class Demo04
 * cookie 获取上次登录时间
 */
public class Demo04 extends HttpServlet {
	
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
	
	response.setContentType("text/html;charset=UTF-8");
		
	 String userName = request.getParameter("username");
	 String password = request.getParameter("password");
	 
	 if("admin".equals(userName) && "123".equals(password)){
		 
		 //获取cookie  first
		 Cookie[] cookies = request.getCookies();
		 
		 //从数组里面找出我们想要的cookie
		 Cookie cookie = CookieUtils.findCookie(cookies, "first");
		 
		 //第一次登录,没有cookie
		 if(cookie == null){
			 Cookie co = new Cookie("first", System.currentTimeMillis()+"");
			 co.setMaxAge(60 * 60);//一个小时
			 response.addCookie(cookie);
			 response.getWriter().write("登录成功" + userName );
		 }else{
			 //第二次登录,有cookie
			 //1.取以前的cookie,第二次登录
			 long firstTime = Long.parseLong(cookie.getValue());
			 
			 //2.输出到界面
			 response.getWriter().write("欢迎您," +userName + ",您上次来访时间是:"+new Date(firstTime));
			 
			 //3.重置登录时间
			 cookie.setValue(System.currentTimeMillis()+"");
			 response.addCookie(cookie);
			 
		 }
		 
		
	 }else{
		 response.getWriter().write("登录失败");
	 }
	}

	
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(request, response);
	}
	
	

}

CookieUtils:

package com.test.utils;

import javax.servlet.http.Cookie;

public class CookieUtils {
	
	/**
	 * 从一个数组中找到具体我们想要的cookie对象
	 * 
	 */
	public static Cookie findCookie(Cookie[] cookies,String name){
		
		if(cookies != null){
			for (Cookie cookie : cookies) {
				if(name.equals(cookie.getName())){
					return cookie;
				}
			}
		}
		
		return null;
		
	}

}

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>登录</title>
</head>
<body>
	<form action="Demo04">
		用户名:<input type="text" name="username"/><br/>
		密    码:<input type="password" name="password"/><br/>
		<input type="submit" value="登录"/>
	</form>
</body>
</html>

web.xml:

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
  <display-name>CookieDemo</display-name>
  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.htm</welcome-file>
    <welcome-file>index.jsp</welcome-file>
    <welcome-file>default.html</welcome-file>
    <welcome-file>default.htm</welcome-file>
    <welcome-file>default.jsp</welcome-file>
  </welcome-file-list>
  <servlet>
    <description></description>
    <display-name>Demo01</display-name>
    <servlet-name>Demo01</servlet-name>
    <servlet-class>com.test.cookie.Demo01</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>Demo01</servlet-name>
    <url-pattern>/Demo01</url-pattern>
  </servlet-mapping>
  <servlet>
    <description></description>
    <display-name>Demo02</display-name>
    <servlet-name>Demo02</servlet-name>
    <servlet-class>com.test.cookie.Demo02</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>Demo02</servlet-name>
    <url-pattern>/Demo02</url-pattern>
  </servlet-mapping>
  <servlet>
    <description></description>
    <display-name>Demo03</display-name>
    <servlet-name>Demo03</servlet-name>
    <servlet-class>com.test.cookie.Demo03</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>Demo03</servlet-name>
    <url-pattern>/Demo03</url-pattern>
  </servlet-mapping>
  <servlet>
    <description></description>
    <display-name>Demo04</display-name>
    <servlet-name>Demo04</servlet-name>
    <servlet-class>com.test.cookie.Demo04</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>Demo04</servlet-name>
    <url-pattern>/Demo04</url-pattern>
  </servlet-mapping>
</web-app>

Cookie 获取上次登录时间

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