code: public static double length(@NonNull LineString lineString,
                                @NonNull @TurfConstants.TurfUnitCriteria String units) {
      List<Point> coordinates = lineString.coordinates();
      return length(coordinates, units);
    }
docs: Takes a {@link LineString} and measures its length in the specified units.
  
  @param lineString geometry to measure
  @param units      one of the units found inside {@link TurfConstants.TurfUnitCriteria}
  @return length of the input line in the units specified
  @see <a href="http://turfjs.org/docs/#linedistance">Turf Line Distance documentation</a>
  @since 1.2.0