Java如何设置Cookie的最长期限？

package org.nhooo.example.servlet;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class CookieExpirationExample extends HttpServlet {

    protected void doGet(HttpServletRequest request,
        HttpServletResponse response) throws ServletException, IOException {
    doPost(request, response);
    }

    protected void doPost(HttpServletRequest request,
        HttpServletResponse response) throws ServletException, IOException {
        String username = request.getParameter("username");
        if (username != null) {
            Cookie cookie = new Cookie("username", username);

            //
            //将Cookie寿命设置为600秒（10分钟）。设定年龄
            // 设为0会删除Cookie，而给它一个负值则会
            // 不存储cookie，当浏览器处于
            // 关闭。
            //
            cookie.setMaxAge(600);
            response.addCookie(cookie);
        }
    }
}