m_FirstBatchDone = true;
  public boolean batchFinished() {    if (getInputFormat() == null) {      throw new IllegalStateException("No input instance format defined");    }    if (getFillWithMissing() && (m_InstanceRange > 0)) {      while (!m_History.empty()) {	push(mergeInstances(null, (Instance) m_History.pop()));      }    }     m_NewBatch = true;    return (numPendingOutput() != 0);  }