code: public LocalTime plusHours(long hoursToAdd) {
          if (hoursToAdd == 0) {
              return this;
          }
          int newHour = ((int) (hoursToAdd % HOURS_PER_DAY) + hour + HOURS_PER_DAY) % HOURS_PER_DAY;
          return create(newHour, minute, second, nano);
      }
docs: Returns a copy of this {@code LocalTime} with the specified number of hours added.
  <p>
  This adds the specified number of hours to this time, returning a new time.
  The calculation wraps around midnight.
  <p>
  This instance is immutable and unaffected by this method call.
  
  @param hoursToAdd  the hours to add, may be negative
  @return a {@code LocalTime} based on this time with the hours added, not null