public function getImplementationByContentClass(core_kernel_classes_Class $contentClass)
    {
        $classname = (string) $contentClass->getOnePropertyValue(new core_kernel_classes_Property(DeliveryContent::PROPERTY_IMPLEMENTATION));
        if (empty($classname)) {
            throw new common_exception_NoImplementation('No implementation found for contentClass ' . $contentClass->getUri());
        }
        if (! class_exists($classname) || ! in_array('oat\\taoDeliveryTemplate\\model\\ContentModel', class_implements($classname))) {
            throw new common_exception_Error('Content implementation '.$classname.' not found, or not compatible for content class '.$contentClass->getUri());
             
        }
        return new $classname();
    }