public static final long getMillisOfUnit(int field) {
		switch (field) {
		case Calendar.DAY_OF_YEAR:
		case Calendar.DAY_OF_MONTH:
			return MILLIS_OF_DAY;
		case Calendar.HOUR:
		case Calendar.HOUR_OF_DAY:
			return MILLIS_OF_HOUR;
		case Calendar.MINUTE:
			return MILLIS_OF_MINUTE;
		case Calendar.SECOND:
			return 1000;
		case Calendar.MILLISECOND:
			return 1;
		default:
			throw new IllegalArgumentException("Unexpected value of field:" + field);
		}
	}