private long generate9DigitId(long now) {
        long lastSeedTime = lastSeedTimeMillis.get();
        if (now - lastSeedTime > 1000 * 60 * 60 * 24) {
            if (lastSeedTimeMillis.compareAndSet(lastSeedTime, now)) {
                randomForMeetingId.reseed();
            } else {
                return generate9DigitId(now);
            }
        }
        return randomForMeetingId.nextInt(1_000_000_000);
    }
@implNote Though the range of the ID is [0, 1,000,000,000), we still use long as it is easy
          to extend the ID range if we need in the future, e.g.: extend to 10 digits.
turms-service/src/main/java/im/turms/service/domain/conference/service/ConferenceService.java