/** Returns the trailers after the HTTP response. May be empty. */
  @Throws(IOException::class)
  fun trailers(): Headers

  /**
   * Cancel this stream. Resources held by this stream will be cleaned up, though not synchronously.
   * That may happen later by the connection pool thread.
   */
  fun cancel()

  /**
   * Carries an exchange. This is usually a connection, but it could also be a connect plan for

      this.state = state;
    }

    @Override
    public boolean cancel(boolean interruptIfRunning) {
      InCompletionOrderState<T> localState = state;
      if (super.cancel(interruptIfRunning)) {
        /*
         * requireNonNull is generally safe: If cancel succeeded, then this Future was still
         * pending, so its `state` field hasn't been nulled out yet.
         *

    stream = http2Connection.newStream(requestHeaders, hasRequestBody)
    // We may have been asked to cancel while creating the new stream and sending the request
    // headers, but there was still no stream to close.
    if (canceled) {
      stream!!.closeLater(ErrorCode.CANCEL)
      throw IOException("Canceled")
    }
    stream!!.readTimeout().timeout(chain.readTimeoutMillis.toLong(), TimeUnit.MILLISECONDS)

    // stop it.
    blockingCallable.waitForStart();

    // This time, cancel the future for the first task. The task remains running, only the future
    // is cancelled.
    future1.cancel(false);

    // Give the second task a chance to (incorrectly) start up while the first task is running.
    // (This is the assertion that fails.)

	m[policy] = p
	return nil
}

func (ies *IAMEtcdStore) loadPolicyDocs(ctx context.Context, m map[string]PolicyDoc) error {
	ctx, cancel := context.WithTimeout(ctx, defaultContextTimeout)
	defer cancel()
	//  Retrieve all keys and values to avoid too many calls to etcd in case of
	//  a large number of policies
	r, err := ies.client.Get(ctx, iamConfigPoliciesPrefix, etcd.WithPrefix())

    }

    @Override
    public boolean isCancelled() {
      return sync.isCancelled();
    }

    @CanIgnoreReturnValue
    @Override
    public boolean cancel(boolean mayInterruptIfRunning) {
      if (!sync.cancel(mayInterruptIfRunning)) {
        return false;
      }
      executionList.execute();
      if (mayInterruptIfRunning) {
        interruptTask();
      }
      return true;

	if testing.Short() {
		t.Skip("skipping test in short mode.")
	}

	dm := NewDRWMutex(ds, "aap")
	dm.refreshInterval = testDrwMutexRefreshInterval

	ctx, cancel := context.WithCancel(context.Background())

	if !dm.GetLock(ctx, cancel, id, source, Options{Timeout: 5 * time.Minute}) {
		t.Fatal("GetLock() should be successful")
	}

	// Make it run twice.
	timer := time.NewTimer(testDrwMutexRefreshInterval * 2)

      @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.

    assertEvents(
      "take plan 1",
      "plan 1 TCP connecting...",
    )

    taskFaker.advanceUntil(500.ms)
    assertEvents(
      "take plan 2",
      "plan 0 cancel",
      "plan 1 cancel",
    )

    taskFaker.advanceUntil(510.ms)
    assertEvents(
      "plan 1 TCP connect canceled",
    )

    taskFaker.advanceUntil(520.ms)
    assertEvents(

  override val isReady = false

  override fun connectTcp() = result

  override fun connectTlsEtc() = result

  override fun handleSuccess() = error("unexpected call")

  override fun cancel() = error("unexpected cancel")

  override fun retry() = error("unexpected retry")