如何判断QueryWrapper有没有查到数据?

怎么判断LambdaQueryWrapper有没有查到数据?
BizMainTemplate bizMainTemplate = new BizMainTemplate();
    QueryWrapper queryWrapper = new QueryWrapper<>();
    queryWrapper.lambda().eq(BizMainTemplate::getDeviceType, bizMainTemplateParam.getDeviceType());
    queryWrapper.lambda().eq(BizMainTemplate::getMainLevel, bizMainTemplateParam.getMainLevel());
    queryWrapper.lambda().eq(BizMainTemplate::getTemplateStatus, bizMainTemplateParam.getTemplateStatus());

    //如果查到了就抛出异常
    if (          ?         ) {
        throw new ServiceException(BizMainTemplateExceptionEnum.HAS_EXIST);
    }else{.....}
判定条件应该怎么写呀

你查询db,难道没个结果嘛?