code: static Interval removeIntervalFromEnd(Interval largeInterval, Interval smallInterval)
    {
      Preconditions.checkArgument(
          largeInterval.getEnd().equals(smallInterval.getEnd()),
          "end should be same. largeInterval[%s] smallInterval[%s]",
          largeInterval,
          smallInterval
      );
      return new Interval(largeInterval.getStart(), smallInterval.getStart());
    }
docs: Removes {@code smallInterval} from {@code largeInterval}.  The end of both intervals should be same.
  
  @return an interval of {@code largeInterval} - {@code smallInterval}.