public long roundCeiling(long instant) {
   int year = get(instant);
   long yearStartMillis = iChronology.getYearMillis(year);
   if (instant != yearStartMillis) {
     // Bump up to start of next year.
     instant = iChronology.getYearMillis(year + 1);
   }
   return instant;
 }
 public long roundFloor(long instant) {
   return iChronology.getYearMillis(get(instant));
 }