code: @Deprecated
  	public SplitStream<T> split(OutputSelector<T> outputSelector) {
  		return new SplitStream<>(this, clean(outputSelector));
  	}
docs: Operator used for directing tuples to specific named outputs using an
  {@link org.apache.flink.streaming.api.collector.selector.OutputSelector}.
  Calling this method on an operator creates a new {@link SplitStream}.
  
  @param outputSelector
  The user defined
  {@link org.apache.flink.streaming.api.collector.selector.OutputSelector}
  for directing the tuples.
  @return The {@link SplitStream}
  @deprecated Please use side output instead.