show current time string like '2021-06-27 17:41:16.681'

anyJava

private static String time() {
      Calendar instance = Calendar.getInstance();
      int year = instance.get(Calendar.YEAR);
      int month = instance.get(Calendar.MONTH) + 1;
      int day = instance.get(Calendar.DAY_OF_MONTH);
      int hour = instance.get(Calendar.HOUR_OF_DAY);
      int minute = instance.get(Calendar.MINUTE);
      int second = instance.get(Calendar.SECOND);
      int millis = instance.get(Calendar.MILLISECOND);
      return String.format(Locale.CHINA, "%04d-%02d-%02d %02d:%02d:%02d.%03d",
              year, month, day, hour, minute, second, millis);
 }