public function getQueryUrl($majorProtocolVersion = null,
        $minorProtocolVersion = null)
    {
        if (isset($this->_url)) {
            $url = $this->_url;
        } else {
            $url = Zend_Gdata_YouTube::VIDEO_URI;
        }
        if ($this->getCategory() !== null) {
            $url .= '/-/' . $this->getCategory();
        }
        $url = $url . $this->getQueryString($majorProtocolVersion,
            $minorProtocolVersion);
        return $url;
    }