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.
         *

  /** 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

   * the event source has already been closed or canceled.
   */
  fun cancel()

  fun interface Factory {
    /**
     * Creates a new event source and immediately returns it. Creating an event source initiates an
     * asynchronous process to connect the socket. Once that succeeds or fails, `listener` will be
     * notified. The caller must cancel the returned event source when it is no longer in use.
     */

          : getUninterruptibly(future, timeoutDuration, timeoutUnit);
    } catch (InterruptedException e) {
      future.cancel(true);
      throw e;
    } catch (ExecutionException e) {
      throw throwCause(e, true /* combineStackTraces */);
    } catch (TimeoutException e) {
      future.cancel(true);
      throw new UncheckedTimeoutException(e);
    }
  }

  @CanIgnoreReturnValue
  @Override

        else -> Socket(route.proxy)
      }
    this.rawSocket = rawSocket

    // Handle the race where cancel() precedes connectSocket(). We don't want to miss a cancel.
    if (canceled) {
      throw IOException("canceled")
    }

    rawSocket.soTimeout = socketReadTimeoutMillis
    try {

    } catch (TimeoutException expected) {
    } finally {
      latch.countDown();
    }
  }

  /**
   * Tests that a canceled future throws a cancellation exception.
   *
   * <p>This method checks the cancel, isCancelled, and isDone methods.
   */
  public void testCanceledFutureThrowsCancellation() throws Exception {

    assertFalse(future.isDone());

  override fun connectTcp() = error("already connected")

  override fun connectTlsEtc() = error("already connected")

  override fun handleSuccess() = connection

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

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

    inFinished: Boolean,
  ) {
    pushQueue.execute("$connectionName[$streamId] onHeaders") {
      val cancel = pushObserver.onHeaders(streamId, requestHeaders, inFinished)
      ignoreIoExceptions {
        if (cancel) writer.rstStream(streamId, ErrorCode.CANCEL)
        if (cancel || inFinished) {
          this.withLock {
            currentPushRequests.remove(streamId)
          }
        }
      }

		for par := 1; par <= 32; par *= 2 {
			b.Run("par="+strconv.Itoa(par*runtime.GOMAXPROCS(0)), func(b *testing.B) {
				defer timeout(60 * time.Second)()
				ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
				defer cancel()
				b.ReportAllocs()
				b.SetBytes(int64(len(payload) * 2))
				b.ResetTimer()
				t := time.Now()
				var ops int64
				var lat int64
				b.SetParallelism(par)

	z.rebalMu.Lock()
	defer z.rebalMu.Unlock()

	r := z.rebalMeta
	if r == nil { // rebalance not running in this node, nothing to do
		return nil
	}

	if cancel := r.cancel; cancel != nil {
		// cancel != nil only on pool leaders
		r.cancel = nil
		cancel()
	}
	return nil
}

// for rebalance trace support
type rebalanceMetrics struct{}

var globalRebalanceMetrics rebalanceMetrics