cookie使用

java页面

package com.yin;

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 CookieDemo extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        req.setCharacterEncoding("UTF-8");
        resp.setCharacterEncoding("UTF-8");
        resp.setContentType("text/html;charset=utf-8");

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

        if(cookies!=null){
            out.write("你上次访问时间:");

            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.toLocaleString());
                };
            }
        }
        else{
            out.write("你这是第一次访问本站");
        }

        Cookie cookie=new Cookie("lastLoginTime",System.currentTimeMillis()+"");
        cookie.setMaxAge(24*60*60);
        resp.addCookie(cookie);

    }

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

　　XML添加路径

    <servlet>
        <servlet-name>name</servlet-name>
        <servlet-class>com.yin.CookieDemo</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>name</servlet-name>
        <url-pattern>/cook</url-pattern>
    </servlet-mapping>

　　查看运行情况

package com.yin;

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 CookieDemo extends HttpServlet {
    @Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        req.setCharacterEncoding("UTF-8");
resp.setCharacterEncoding("UTF-8");
resp.setContentType("text/html;charset=utf-8");

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

        if(cookies!=null){
            out.write("你上次访问时间:");

            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.toLocaleString());
};
}
        }
        else{
            out.write("你这是第一次访问本站");
}

        Cookie cookie=new Cookie("lastLoginTime",System.currentTimeMillis()+"");
cookie.setMaxAge(24*60*60);
resp.addCookie(cookie);

}

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