public void addSink(String streamName,String targetOperName,String targetPortName){
  addSinks(streamName,getInputPort(targetOperName,targetPortName));
}

public void addSink ( String streamName , String targetOperName , String targetPortName ) { addSinks ( streamName , getInputPort ( targetOperName , targetPortName ) ) ; }
add sink to an existing stream to logical plan .
