protected void doGet(HttpServletRequest req, HttpServletResponse resp)            throws ServletException, IOException {                // 判断cookie是否有登录信息        Cookie[] cookies = req.getCookies();        boolean isLogin = false;        for(Cookie c : cookies){            if("loginInfo".equals(c.getName())){                String v = c.getValue();                if(v!=null && !v.equals("")){                    isLogin = true;                }            }        }                // 有，登录通过        // 没有，登录验证，设置登录信息，设置cookie有效时间        if(isLogin){            System.out.println("用户已登录");        }else{            System.out.println("用户未登录");            System.out.println("用户信息验证通过");            Cookie c = new Cookie("loginInfo", "loginInfo");            c.setMaxAge(Integer.parseInt(login_keep+""));            resp.addCookie(c);        }            }