private function getTranslatableFields($className)
    {
        // Here we use reflection to get the class
        $reflectionClass = new \ReflectionClass($className);
        $translatableFields = array();
        // and its entities
        $reflectionProperties = $reflectionClass->getProperties();
        foreach ($reflectionProperties as $reflectionProperty) {
            // We use the annotation reader to get the properties annotated with the "Translatable" annotation
            $propertyAnnotation = $this->annotationReader->getPropertyAnnotation($reflectionProperty, 'Gedmo\Mapping\Annotation\Translatable');
            if ($propertyAnnotation) {
                // In this case we have to get the property name and its type in the mapping annotation
                $mappingAnnotation = $this->annotationReader->getPropertyAnnotation($reflectionProperty, 'Doctrine\ORM\Mapping\Column');
                $translatableFields[$reflectionProperty->getName()] = $mappingAnnotation->type;
            }
        }
        return $translatableFields;
    }