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 {
//設置響應的消息體的數據格式以及編碼
response.setContentType("text/html;charset=utf-8");
//獲取所有Cookie
Cookie[] cookies = request.getCookies();
boolean flag = false;//沒有cookies爲lastTime
//遍歷cookies數組
if(cookies != null && cookies.length > 0) {
for (Cookie cookie : cookies) {
//獲取cookie的名稱
String name = cookie.getName();
//判斷名稱是否是:lastTime
if ("lastTime".equals(name)) {
//有該Cookie,不是第一次訪問
flag = true;//有lastTime的cookie
//響應數據
//獲取Cookie的value,時間
String value = cookie.getValue();
System.out.println("解碼前:" + value);
//URL解碼:
value = URLDecoder.decode(value, "utf-8");
System.out.println("解碼後:" + value);
response.getWriter().write("<h1>歡迎回來,您上次訪問的時間爲:" + value + "</h1>");
//設置Cookie的value
//獲取當前時間的字符串,重新設置Cookie的值,重新發送cookie
Date date = new Date();
//設置時間格式
SimpleDateFormat sdf = new SimpleDateFormat("yyyy年MM月dd日 HH:mm:ss");
//把時間格式化
String str_date = sdf.format(date);
System.out.println("編碼前:" + str_date);
//URL編碼
str_date = URLEncoder.encode(str_date, "utf-8");
System.out.println("編碼後:" + str_date);
cookie.setValue(str_date);
//設置cookie的存活時間
cookie.setMaxAge(60 * 60 * 24 * 30);//一個月
//重新發送cookie
response.addCookie(cookie);
break;
}
}
}
if(cookies == null || cookies.length == 0 || flag == false){
//沒有,第一次訪問
//設置Cookie的value
//獲取當前時間的字符串,重新設置Cookie的值,重新發送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("編碼前:"+str_date);
//URL編碼
str_date = URLEncoder.encode(str_date, "utf-8");
System.out.println("編碼後:"+str_date);
//給lastTime重新賦值
Cookie cookie = new Cookie("lastTime", str_date);
//設置cookie的存活時間
cookie.setMaxAge(60*60*24*30);//一個月
response.addCookie(cookie);
response.getWriter().write("<h1>您好,歡迎您首次訪問</h1>");
}
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request, response);
}
}
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