case classPeriodicTaskImpl[U](task: () ⇒ U, initialDelay: Duration, period: Duration, scheduledExecutorService: ScheduledExecutorService, reportFailure: (Throwable) ⇒ Unit) extends PeriodicTask with Product with Serializable
case classScheduledDelayedFutureImpl[A](task: () ⇒ A, delay: Duration, scheduledExecutorService: ScheduledExecutorService)(implicit ec: ExecutionContext) extends DelayedFuture[A] with DelegatedFuture[A] with Product with Serializable