《Cookie案例2》——————利用Cookie记录客户端上次访问时间

(2) 利用Cookie记录客户端上次访问时间

1.接收客户端带过来Cookie的信息

2.从数组中查找指定名称Cookie，如果找不到(第一次访问)，输出一个欢迎

如果找到了(不是第一次)，取出上次的访问时间，显示到页面

3.记录系统当前时间

4.利用Cookie回写当前时间

package com.offcn.servlet;

import java.io.IOException;
import java.io.PrintWriter;
import java.text.SimpleDateFormat;
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.offcn.utils.CookieUtil;

public class Cookie2Servlet extends HttpServlet {
	
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		this.doPost(request, response);
	}

	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		response.setContentType("text/html;charset=utf-8");
		PrintWriter out = response.getWriter();
		Cookie[] cs = request.getCookies();
		Cookie c = CookieUtil.findCookiesByName(cs, "lastVisitedTime");
		if(c==null){
			out.print("<h1>欢迎第一次访问</h1>");
		}else{
			String value = c.getValue();
			out.print("<h1>上次访问的时间为："+value+"</h1>");
		}
		Date d = new Date();
		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd#HH:mm:ss");
		String date = sdf.format(d);
		Cookie cookie = new Cookie("lastVisitedTime",date);
		cookie.setMaxAge(10000);
		response.addCookie(cookie);
	}

}