public function setItemCountPerPage($itemCountPerPage = -1)
    {
        $this->itemCountPerPage = (int) $itemCountPerPage;
        if ($this->itemCountPerPage < 1) {
            $this->itemCountPerPage = $this->getTotalItemCount();
        }
        $this->pageCount        = $this->_calculatePageCount();
        $this->currentItems     = null;
        $this->currentItemCount = null;

        return $this;
    }