docs: public void addVirtualSelectNode(Integer originalId, Integer virtualId, List<String> selectedNames) {
  
  		if (virtualSelectNodes.containsKey(virtualId)) {
  			throw new IllegalStateException("Already has virtual select node with id " + virtualId);
  		}
  
  		virtualSelectNodes.put(virtualId,
  				new Tuple2<Integer, List<String>>(originalId, selectedNames));
  	}