private function configureSubjectRelativeMapping(LoadClassMetadataEventArgs $eventArgs)
    {
        /** @var ClassMetadata $metadata */
        $metadata = $eventArgs->getClassMetadata();
        $class = $metadata->getName();

        // Check class
        if (!is_subclass_of($class, SubjectRelativeInterface::class)) {
            return;
        }

        // Don't add twice
        if (in_array($class, $this->relativeClassCache)) {
            return;
        }

        // Map embedded
        $this
            ->getSubjectIdentityMapper($eventArgs->getEntityManager())
            ->processClassMetadata($metadata, 'subjectIdentity', 'subject_');

        // Cache class
        $this->relativeClassCache[] = $class;
    }