/**
  *
  * @param core_kernel_classes_Class $itemClass
  * @param oat\taoQtiItem\model\qti\Item $qtiModel
  * @throws common_exception_Error
  * @throws \common_Exception
  * @return core_kernel_classes_Resource
  */
 protected function createRdfItem(core_kernel_classes_Class $itemClass, Item $qtiModel)
 {
     $itemService = taoItems_models_classes_ItemsService::singleton();
     $qtiService = Service::singleton();
     if (!$itemService->isItemClass($itemClass)) {
         throw new common_exception_Error('provided non Itemclass for ' . __FUNCTION__);
     }
     $rdfItem = $itemService->createInstance($itemClass);
     //set the QTI type
     $itemService->setItemModel($rdfItem, new core_kernel_classes_Resource(ItemModel::MODEL_URI));
     //set the label
     $label = '';
     if ($qtiModel->hasAttribute('label')) {
         $label = $qtiModel->getAttributeValue('label');
     }
     if (empty($label)) {
         $label = $qtiModel->getAttributeValue('title');
     }
     $rdfItem->setLabel($label);
     //save itemcontent
     if (!$qtiService->saveDataItemToRdfItem($qtiModel, $rdfItem)) {
         throw new \common_Exception('Unable to save item');
     }
     return $rdfItem;
 }