private void testRange(boolean aSuccess, int aYearIncr, int aMonthIncr, int aDayIncr, int aHourIncr, int aMinIncr, int aSecIncr, int aNanosIncr){
    DateTime from = new DateTime("0001-02-28 11:23:56.0");
    try { 
      DateTime result = from.plus(aYearIncr, aMonthIncr, aDayIncr, aHourIncr, aMinIncr, aSecIncr, aNanosIncr, DateTime.DayOverflow.LastDay);
      if(!aSuccess){
        fail();
      }
    }
    catch(IllegalArgumentException ex){
      if(aSuccess){
        fail();
      }
    }
  }