@WebServlet("/servletcookie")
public class Servletcookie 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");
//1.获取所有Cookie
Cookie[] cookies = request.getCookies();
boolean flag = false;//没有cookie为lastTime
//2.遍历cookie数组
if (cookies != null && cookies.length > 0) {
for (Cookie cookie : cookies) {
//3.获取cookie的名称
String name = cookie.getName();
//4.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
getTime(response, 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);
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);*/
Cookie cookie = new Cookie("lastTime",null);
getTime(response, cookie);
response.getWriter().write("<h1>您好,欢迎您首次访问</h1>");
}
}
private void getTime(HttpServletResponse response, Cookie cookie) throws UnsupportedEncodingException {
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);
cookie.setValue(str_date);
//设置cookie的存活时间
cookie.setMaxAge(60 * 60 * 24 * 30);//一个月
response.addCookie(cookie);
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request, response);
}
}
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