private String _generateRegKey(HttpServletRequest request, HttpServletResponse response) {
    String REG_VALUE = null;
    String code = RandomStringUtils.randomAlphanumeric(LENGTH).toUpperCase();
    code.replace('0', 'W');
    code.replace('o', 'R');
    code.replace('I', 'E');
    code.replace('1', 'T');

    REG_VALUE = CryptUtils.encrypt(code, key);

    RequestUtils.setCookie(request, response, COOKIE_NAME, REG_VALUE, 1440, true); // 保存1天

    return code;
  }
  /**
   * 检查验证码是否正确
   *
   * @param req
   * @return
   */
  public boolean validate(HttpServletRequest req) {
    Cookie cke = RequestUtils.getCookie(req, COOKIE_NAME);
    if (cke == null || StringUtils.isNotBlank(cke.getValue())) {
      return false;
    }

    String value = cke.getValue();
    String code1 = null;
    try {
      code1 = CryptUtils.decrypt(value, key);
    } catch (Exception e) {
      return false;
    }
    String code2 = req.getParameter("verifyCode");
    return StringUtils.equalsIgnoreCase(code1, code2);
  }