public EntityRef deserialize(EntityData.PackedEntity entityData) {
   EntityBuilder target;
   if (entityData.hasParentPrefabUri()) {
     target = entityManager.newBuilder(entityData.getParentPrefabUri());
   } else {
     target = entityManager.newBuilder();
   }
   deserializeOnto(target, entityData);
   if (entityData.hasId()) {
     return entityManager.createEntityWithId(entityData.getId(), target.iterateComponents());
   } else {
     return target.build();
   }
 }