public OptionalLong minByLong(LongUnaryOperator keyExtractor){
  long[] result=collect(null,null,null);
  return result[2] == 1 ? OptionalLong.of(result[0]) : OptionalLong.empty();
}

public OptionalLong minByLong ( LongUnaryOperator keyExtractor ) { long [ ] result = collect ( null , null , null ) ; return result [ 2 ] == 1 ? OptionalLong . of ( result [ 0 ] ) : OptionalLong . empty ( ) ; }
returns the minimum element of this stream according to the provided key extractor function . < p > this is a terminal operation .
