前端操作cookie：

var cookie = {    set:function(key,val,time){//设置cookie方法        var date=new Date(); //获取当前时间        var expiresDays=time;  //将date设置为n天以后的时间        date.setTime(date.getTime()+expiresDays*24*3600*1000); //格式化为cookie识别的时间        document.cookie=key + "=" + val +";expires="+date.toGMTString();  //设置cookie    },    get:function(key){//获取cookie方法        /*获取cookie参数*/        var getCookie = document.cookie.replace(/[ ]/g,"");  //获取cookie，并且将获得的cookie格式化，去掉空格字符        var arrCookie = getCookie.split(";")  //将获得的cookie以"分号"为标识 将cookie保存到arrCookie的数组中        var tips;  //声明变量tips        for(var i=0;i

后端操作cookie：

package gac.xdp.cookie;import java.io.IOException;import java.io.PrintWriter;import java.util.Date;import javax.servlet.ServletException;import javax.servlet.http.Cookie;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;/** * @author gacl * cookie实例：获取用户上一次访问的时间 */public class CookieDemo01 extends HttpServlet {    public void doGet(HttpServletRequest request, HttpServletResponse response)            throws ServletException, IOException {        //设置服务器端以UTF-8编码进行输出        response.setCharacterEncoding("UTF-8");        //设置浏览器以UTF-8编码进行接收,解决中文乱码问题        response.setContentType("text/html;charset=UTF-8");        PrintWriter out = response.getWriter();        //获取浏览器访问访问服务器时传递过来的cookie数组        Cookie[] cookies = request.getCookies();        //如果用户是第一次访问，那么得到的cookies将是null        if (cookies!=null) {            out.write("您上次访问的时间是：");            for (int i = 0; i < cookies.length; i++) {                Cookie cookie = cookies[i];                if (cookie.getName().equals("lastAccessTime")) {                    Long lastAccessTime =Long.parseLong(cookie.getValue());                    Date date = new Date(lastAccessTime);                    out.write(date.toLocaleString());                }            }        }else {            out.write("这是您第一次访问本站！");        }                //用户访问过之后重新设置用户的访问时间，存储到cookie中，然后发送到客户端浏览器        Cookie cookie = new Cookie("lastAccessTime", System.currentTimeMillis()+"");//创建一个cookie，cookie的名字是lastAccessTime        //将cookie对象添加到response对象中，这样服务器在输出response对象中的内容时就会把cookie也输出到客户端浏览器        response.addCookie(cookie);    }    public void doPost(HttpServletRequest request, HttpServletResponse response)            throws ServletException, IOException {        doGet(request, response);    }}