@Override
  public void clear() {
    synchronized (LOCK) {
      if (getEditor() == null) return;
      // real document content will be cleared on next flush;
      myDeferredBuffer.clear();
    }
    if (!myFlushAlarm.isDisposed()) {
      cancelAllFlushRequests();
      addFlushRequest(0, CLEAR);
      cancelHeavyAlarm();
    }
  }
@Override
  public void clear()