@Override
  public void force() throws IOException {
    if (myIsReadOnly) return;
    if (myDoTrace) LOG.info("Forcing " + myStorageFile);
    if (myWal != null) {
      myWal.flush();
    }
    getWriteLock().lock();
    try {
      doForce();
    }
    finally {
      getWriteLock().unlock();
    }
  }
@Override
  public void force()