inputFuture.cancel(true); // argument is ignored
    assertThrows(CancellationException.class, () -> resultFuture.get());
  }

  public void testFutureGetThrowsCancellationIfOutputCancelled() throws Exception {
    inputFuture.set(SLOW_OUTPUT_VALID_INPUT_DATA);
    outputFuture.cancel(true); // argument is ignored

 * Prefer to alternate IP addresses from different address families, (IPv6 / IPv4), starting with IPv6.
 * Don't start a new attempt until 250 ms after the most recent attempt was started.
 * Keep whichever TCP connection succeeds first and cancel all the others.

    assertFailed(future, cause);
  }

  public void testCanceled() throws Exception {
    assertThat(future.cancel(false /* mayInterruptIfRunning */)).isTrue();
    assertCancelled(future, false);
  }

  public void testInterrupted() throws Exception {
    assertThat(future.cancel(true /* mayInterruptIfRunning */)).isTrue();
    assertCancelled(future, true);
  }

// The function will block until the context is canceled.
// There should only ever be one scanner running per cluster.
func runDataScanner(ctx context.Context, objAPI ObjectLayer) {
	ctx, cancel := globalLeaderLock.GetLock(ctx)
	defer cancel()

	// Load current bloom cycle
	var cycleInfo currentScannerCycle

	buf, _ := readConfig(ctx, objAPI, dataUsageBloomNamePath)
	if len(buf) == 8 {

   * write.
   *
   * 2. visibility of the writes to an afterDone() call triggered by cancel():
   *
   * Since these fields are non-final that means that TimeoutFuture is not being 'safely published',
   * thus a motivated caller may be able to expose the reference to another thread that would then
   * call cancel() and be unable to cancel the delegate.

type LockContext struct {
	ctx    context.Context
	cancel context.CancelFunc
}

// Context returns lock context
func (l LockContext) Context() context.Context {
	return l.ctx
}

// Cancel function calls cancel() function
func (l LockContext) Cancel() {
	if l.cancel != nil {
		l.cancel()
	}
}

// newNSLock - return a new name space lock map.

    /**
     * Last fragment flag - indicates last fragment of a multi-fragment message
     */
    int DCERPC_LAST_FRAG = 0x02; /* Last fragment */
    /**
     * Pending cancel flag - indicates cancel was pending at sender
     */
    int DCERPC_PENDING_CANCEL = 0x04; /* Cancel was pending at sender */
    /**
     * Reserved flag for future use
     */
    int DCERPC_RESERVED_1 = 0x08;
    /**
     * Supports concurrent multiplexing flag.

}

func mergeContext(ctx1, ctx2 context.Context) (context.Context, context.CancelFunc) {
	ctx, cancel := context.WithCancel(context.Background())
	go func() {
		select {
		case <-ctx1.Done():
		case <-ctx2.Done():
		// The lock acquirer decides to cancel, exit this goroutine
		case <-ctx.Done():
		}

		cancel()
	}()
	return ctx, cancel
}

func (ld sharedLock) GetLock(ctx context.Context) (context.Context, context.CancelFunc) {

      @Override
      @SuppressWarnings("Interruption") // We are propagating an interrupt from a caller.
      public void cancel(boolean mayInterruptIfRunning) {
        /*
         * Lock to ensure that a task cannot be rescheduled while a cancel is ongoing.
         *
         * In theory, cancel() could execute arbitrary listeners -- bad to do while holding a lock.

    events.add(Failure(t, response, t?.message ?: response?.body?.string()))
    drainCancelQueue(eventSource)
  }

  private fun drainCancelQueue(eventSource: EventSource) {
    if (cancel) {
      cancel = false
      eventSource.cancel()
    }
  }

  private fun nextEvent(): Any =
    events.poll(10, TimeUnit.SECONDS)
      ?: throw AssertionError("Timed out waiting for event.")

  fun assertExhausted() {