package cn.itheima.Cookie;
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.net.URLDecoder;
import java.net.URLEncoder;
import java.text.SimpleDateFormat;
import java.util.Date;
@WebServlet("/CookieTest1")
public class CookieTest1 extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//设置响应的消息体的数据格式以及编码
response.setContentType("text/html;charset=utf-8");
//获取所有Cookie
Cookie[] cookies = request.getCookies();
boolean flag = false;//没有cookies为lastTime
//遍历cookies数组
if(cookies != null && cookies.length > 0) {
for (Cookie cookie : cookies) {
//获取cookie的名称
String name = cookie.getName();
//判断名称是否是:lastTime
if ("lastTime".equals(name)) {
//有该Cookie,不是第一次访问
flag = true;//有lastTime的cookie
//响应数据
//获取Cookie的value,时间
String value = cookie.getValue();
System.out.println("解码前:" + value);
//URL解码:
value = URLDecoder.decode(value, "utf-8");
System.out.println("解码后:" + value);
response.getWriter().write("<h1>欢迎回来,您上次访问的时间为:" + value + "</h1>");
//设置Cookie的value
//获取当前时间的字符串,重新设置Cookie的值,重新发送cookie
Date date = new Date();
//设置时间格式
SimpleDateFormat sdf = new SimpleDateFormat("yyyy年MM月dd日 HH:mm:ss");
//把时间格式化
String str_date = sdf.format(date);
System.out.println("编码前:" + str_date);
//URL编码
str_date = URLEncoder.encode(str_date, "utf-8");
System.out.println("编码后:" + str_date);
cookie.setValue(str_date);
//设置cookie的存活时间
cookie.setMaxAge(60 * 60 * 24 * 30);//一个月
//重新发送cookie
response.addCookie(cookie);
break;
}
}
}
if(cookies == null || cookies.length == 0 || flag == false){
//没有,第一次访问
//设置Cookie的value
//获取当前时间的字符串,重新设置Cookie的值,重新发送cookie
Date date = new Date();
SimpleDateFormat sdf = new SimpleDateFormat("yyyy年MM月dd日 HH:mm:ss");
String str_date = sdf.format(date);
System.out.println("编码前:"+str_date);
//URL编码
str_date = URLEncoder.encode(str_date, "utf-8");
System.out.println("编码后:"+str_date);
//给lastTime重新赋值
Cookie cookie = new Cookie("lastTime", str_date);
//设置cookie的存活时间
cookie.setMaxAge(60*60*24*30);//一个月
response.addCookie(cookie);
response.getWriter().write("<h1>您好,欢迎您首次访问</h1>");
}
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request, response);
}
}
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