docs: public void putPersistent(DbEntity e) {
      CachedDbEntity cachedDbEntity = new CachedDbEntity();
      cachedDbEntity.setEntity(e);
      cachedDbEntity.setEntityState(PERSISTENT);
      cachedDbEntity.determineEntityReferences();
      cachedDbEntity.makeCopy();
  
      putInternal(cachedDbEntity);
    }