/**
  * Returns the shop id or null
  *
  * @return integer|null
  */
 protected function getShopId()
 {
     // Sub-objects
     $oLanguageShop = $this->Order->getLanguageSubShop();
     $Shop = $this->Order->getShop();
     // Shop
     if ($Shop || $oLanguageShop) {
         try {
             if ($Shop->getId() != $oLanguageShop->getId()) {
                 return PlentymarketsMappingController::getOrdersByShopwareID($oLanguageShop->getId());
             } else {
                 return PlentymarketsMappingController::getOrdersByShopwareID($Shop->getId());
             }
         } catch (PlentymarketsMappingExceptionNotExistant $E) {
         }
     }
     return null;
 }