Elegant non-linear task scheduling?

I'd like to schedule a task to happen frequently at first, then less frequently over time. I would prefer not to add a dependency to Quartz just for this.

With the standard Java library, the best I've come up with is a series of one-shot tas开发者_JAVA技巧ks, followed by a less-frequent linear schedule:

    ScheduledExecutorService executor = Executors.newScheduledThreadPool(1);
    myRunnable = new MyRunnable();
    executor.schedule( myRunnable, 0, TimeUnit.SECONDS );
    executor.schedule( myRunnable, 5, TimeUnit.SECONDS );
    executor.schedule( myRunnable, 10, TimeUnit.SECONDS );
    executor.schedule( myRunnable, 15, TimeUnit.SECONDS );
    executor.schedule( myRunnable, 30, TimeUnit.SECONDS );
    executor.schedule( myRunnable, 45, TimeUnit.SECONDS );
    executor.scheduleWithFixedDelay( myRunnable, 60, 300, TimeUnit.SECONDS );

Is there a more elegant approach?

You can let the task trigger its next execution and always increment some 'wait seconds' after each completion?

As an extension to what @dcn suggested, you can write a delegating class that does the scheduling:

public class NonLinearScheduling {

  public static void taperingOffSchedule(final ScheduledExecutorService executor,
                                         final Runnable task,
                                         final long initialDelay,
                                         final TimeUnit unit,
                                         final double decayMultiplier) {
    assert initialDelay > 0;
    assert decayMultiplier > 1.0;
    Runnable repeater = new Runnable() {
        double nextDelay = initialDelay;
        public void run() {
            task.run();
            nextDelay *= decayMultiplier;
            executor.schedule(this, (long) nextDelay, unit);
        }
    };
    executor.schedule(repeater, initialDelay, unit);
  }
}

Note also that instead of the repeater being an anonymous Runnable, it can become a publicly known type that allows future scheduling to be cancelled, etc:

public interface Repeater extends Runnable {
  void stopRepeating();
}


public class NonLinearScheduling {
  public static Repeater taperingOffSchedule(...) { ... }

  private static class NonLinearRepeater implements Repeater {
    private final AtomicBoolean _repeat = new AtomicBoolean(true);

    public void stopRepeating() {
      _repeat.set(false);
    }

    public void run() {
      if (_repeat.get()) {
        ...          
      }
    }
  }
}