@Override
 public void editUserEmail(Long userId, String email) {
   if (email == null || email.equals("")) {
     throw new ServiceException(ErrService.UserS.ACC_102, "电子邮箱格式错误。");
   }
   User u = userDao.queryByEnEmail(email);
   if (u != null) {
     throw new ServiceException(ErrService.UserS.ACC_102, "该电子邮箱已经被激活。");
   }
   User user = userDao.queryById(userId);
   if (!email.equals(user.getEmail())) {
     userDao.updateEmail(userId, email);
   }
 }