Java后端Cookie实现（时间戳）代码实例

package com.lei;

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 java.io.IOException;
import java.io.PrintWriter;
import java.util.Date;

public class CookieDemo01 extends HttpServlet {
  @Override
  protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
    req.setCharacterEncoding("utf-16");
    resp.setCharacterEncoding("utf-16");

    PrintWriter out =resp.getWriter();
    Cookie[] cookies=req.getCookies();

    if(cookies!=null)
    {
      out.write("您上一次访问时间为：");

      for(int i=0;i< cookies.length;i++)
      {
        Cookie cookie=cookies[i];
        if(cookie.getName().equals("lastLoginTime"))
        {
          long lastLoginTime=Long.parseLong(cookie.getValue());
          Date date=new Date(lastLoginTime);
          out.write(date.toString());

        }
      }
    }
    else{
      out.write("first time come to this website!");
    }
    Cookie cookie=new Cookie("lastLoginTime",System.currentTimeMillis()+"");
    resp.addCookie(cookie);
  }

  @Override
  protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
    doGet(req, resp);
  }
}

<!DOCTYPE web-app PUBLIC
    "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
    "http://java.sun.com/dtd/web-app_2_3.dtd" >

<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
           http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
     version="4.0"
     metadata-complete="true">

<servlet>
  <servlet-name>cookie</servlet-name>
  <servlet-class>com.lei.CookieDemo01</servlet-class>
</servlet>
<servlet-mapping>
  <servlet-name>cookie</servlet-name>
  <url-pattern>/cookie</url-pattern>
</servlet-mapping>
</web-app>