code: private static Calendar getInstanceInternal(TimeZone tz, ULocale locale) {
          if (locale == null) {
              locale = ULocale.getDefault(Category.FORMAT);
          }
          if (tz == null) {
              tz = TimeZone.getDefault();
          }
  
          Calendar cal = createInstance(locale);
          cal.setTimeZone(tz);
          cal.setTimeInMillis(System.currentTimeMillis());
          return cal;
      }
docs: /*
  All getInstance implementations call this private method to create a new
  Calendar instance.