protected function loadSchemaLocations(DOMElement $itemData){
        $schemaLoc = preg_replace('/\s+/', ' ', trim($itemData->getAttributeNS($itemData->lookupNamespaceURI('xsi'), 'schemaLocation')));
        $schemaLocToken = explode(' ', $schemaLoc);
        $schemaCount = count($schemaLocToken);
        if($schemaCount%2){
            throw new ParsingException('invalid schema location');
        }
        for($i=0; $i<$schemaCount; $i=$i+2){
            $this->item->addSchemaLocation($schemaLocToken[$i], $schemaLocToken[$i+1]);
        }
    }