@Override
    public <T> Future<T> schedule(final ScheduledExecutorService executor,
                                  final Callable<T> callable, long delayMs) {
        return executor.schedule(callable, delayMs, TimeUnit.MILLISECONDS);
    }
A scheduler implementation that uses the system clock.

Use Scheduler.SYSTEM instead of constructing an instance of this class.
clients/src/main/java/org/apache/kafka/common/utils/SystemScheduler.java