Cookie——获取上次来访时间

CookieDemo类：

package com.itheima.servlet;

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.itheima.util.CookieUtil;

@SuppressWarnings("serial")
public class CookieDemo03 extends HttpServlet{
	@Override
	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
			 Cookie[] cookies = request.getCookies();
			 
			 //在数组里面找出我们想要的cookie
			 
			 Cookie cookie = CookieUtil.findCookie(cookies, "last");
			 if (cookie == null) {
				Cookie c = new Cookie("last", System.currentTimeMillis()+"");
				c.setMaxAge(60*60);
				response.addCookie(c);
				response.getWriter().write("登录成功，欢迎您 "+username);
			}else {
				//1.取以前的cookie
				long lastVisitTime = Long.parseLong(cookie.getValue());
				//2.输出到界面
				response.getWriter().write("登录成功，欢迎您 "+username+",上次来访时间是"+new Date(lastVisitTime));
				//3.重置登录的时间
				cookie.setValue(System.currentTimeMillis()+"");
				response.addCookie(cookie);
			}
			 
		}else {
			response.getWriter().write("登录失败");
		}
		
	}
	
	@Override
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		doGet(request, response);
	}
}

用到的CookieUtil类


package com.itheima.util;

import javax.servlet.http.Cookie;

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

Cookie_login.html

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
	<form action="CookieDemo03">
		账号：<input type="text" name="username"/><br>
		密码：<input type="password" name="password"/><br>
		<input type="submit" value="登录"/>
	</form>
</body>
</html>

xml配置

<servlet>
    <servlet-name>CookieDemo03</servlet-name>
    <servlet-class>com.itheima.servlet.CookieDemo03</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>CookieDemo03</servlet-name>
    <url-pattern>/CookieDemo03</url-pattern>
  </servlet-mapping>

正在尝试写博客，把会的分享给你们，如有写的不好的地方，希望指点一下，谢谢！

Cookie——获取上次来访时间

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