/**
  * {@inheritdoc}
  */
 public function loadClassMetadata(LoadClassMetadataEventArgs $event)
 {
     $map = [];
     $metadata = $event->getClassMetadata();
     foreach ($metadata->discriminatorMap as $discriminatorName => $discriminatorClass) {
         if (isset($this->resolveTargetEntities[$discriminatorClass])) {
             $map[$discriminatorName] = $this->resolveTargetEntities[$discriminatorClass]['targetDocument'];
         }
     }
     $metadata->setDiscriminatorMap($map);
     parent::loadClassMetadata($event);
 }