if (pageSize <= 0) {
            throwPagingPageSizeNotPlusException(pageSize, pageNumber);
        }
        fetchFirst(pageSize);
        xfetchPage(pageNumber);
    }

    protected void throwPagingPageSizeNotPlusException(int pageSize, int pageNumber) {
        createCBExThrower().throwPagingPageSizeNotPlusException(this, pageSize, pageNumber);
    }