package com.neuedu.servlet;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import 
 
java.io.PrintWriter;
import java.text.SimpleDateFormat;
import java.util.Date;

/**
 * Created by Administrator on 2016/11/28 0028.
 */
@WebServlet(name = "timeServlet",urlPatterns = "/lasttime")
public class timeServlet extends HttpServlet
{
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws 
 
ServletException, IOException
    {

    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
    {
        response.setContentType("text/html;charset=utf-8");
        response.setCharacterEncoding("utf-8");
        //取得當前時間字串
SimpleDateFormat sdf=new 
 
SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
        String curdate=sdf.format(new Date());
        PrintWriter pw=response.getWriter();
        Cookie [] cookies=request.getCookies();
        String strtime="";
        boolean isfirstvisit=true;//假定當前是第一次訪問
if(cookies!=null){
            for(Cookie c:cookies){
                //看cookie中是否含有名稱是lasttime的cookie，如果有，不是第一次訪問（之前設定過這個cookie了）
//如果迴圈一圈都沒有發現名稱是lasttime的cookie，說明是第一次訪問
if("lasttime".equals(c.getName())){
                    isfirstvisit=false;
                    strtime=c.getValue();
                }
            }
        }
        //將當前時間儲存到cookie中
Cookie c=new Cookie("lasttime",curdate);
        response.addCookie(c);
        if(!isfirstvisit){
            pw.print("上次訪問時間是"+curdate);
            pw.print("當前時間是"+strtime);
        }
        else {
            pw.print("當前時間是"+curdate);
        }

    }
}