code: public static boolean isUtc(final TimeZone timezone) {
  //        return timezone.hasSameRules(TimeZone.getTimeZone(UTC_ID));
  //        return timezone.getRawOffset() == 0;
          return UTC_ID.equals(timezone.getID())
              || IBM_UTC_ID.equals(timezone.getID());
      }
docs: Indicates whether the specified timezone is equivalent to
  UTC time.
  @param timezone a timezone instance
  @return true if the timezone is UTC time, otherwise false