code: protected void emitWithOnlyAnchorAndStream(StreamMessage message, String streamId)
      {
          getCollector().emit(streamId, this.getExecutingTuple(), new Values("", message));
      }
docs: Use anchor function(child message failed. notify fail to parent message.), and not use this class's key history function.<br>
  Send message to downstream component with streamId.<br>
  Use following situation.
  <ol>
  <li>Not use this class's key history function.</li>
  <li>Use storm's fault detect function.</li>
  </ol>
  
  @param message sending message
  @param streamId streamId