throw new Exception("No input instance format defined");
throw new NullPointerException("No input instance format defined");
  public boolean input(Instance instance) throws Exception {    if (m_InputFormat == null) {      throw new Exception("No input instance format defined");    }    if (m_NewBatch) {      m_OutputQueue = new Queue();      m_NewBatch = false;    }    bufferInput(instance);    return false;  }