public static final String RUNNING = "running";

    /** Status constant representing done/completed state. */
    public static final String DONE = "done";

    /** Status constant representing successful operation. */
    public static final String OK = "ok";

    /** Status constant representing failed operation. */
    public static final String FAIL = "fail";

    /** Status constant representing stopped state. */

    state = STATE_WRITING_REQUEST_BODY
    return ChunkedSink()
  }

  private fun newKnownLengthSink(): Sink {
    check(state == STATE_OPEN_REQUEST_BODY) { "state: $state" }
    state = STATE_WRITING_REQUEST_BODY
    return KnownLengthSink()
  }

  private fun newFixedLengthSource(
    url: HttpUrl,
    length: Long,
  ): Source {
    check(state == STATE_OPEN_RESPONSE_BODY) { "state: $state" }

      for any such Derivative Works as a whole, provided Your use,
      reproduction, and distribution of the Work otherwise complies with
      the conditions stated in this License.

   5. Submission of Contributions. Unless You explicitly state otherwise,
      any Contribution intentionally submitted for inclusion in the Work
      by You to the Licensor shall be under the terms and conditions of

      for any such Derivative Works as a whole, provided Your use,
      reproduction, and distribution of the Work otherwise complies with
      the conditions stated in this License.

   5. Submission of Contributions. Unless You explicitly state otherwise,
      any Contribution intentionally submitted for inclusion in the Work
      by You to the Licensor shall be under the terms and conditions of

        AggregateFutureState<?> state, @Nullable Set<Throwable> expect, Set<Throwable> update) {
      synchronized (state) {
        if (state.seenExceptionsField == expect) {
          state.seenExceptionsField = update;
        }
      }
    }

    @Override
    int decrementAndGetRemainingCount(AggregateFutureState<?> state) {
      synchronized (state) {
        return --state.remainingField;
      }

    //            (__)\       )\/\
    //                ||----w |
    //                ||     ||
    Runnable state = get();
    Blocker blocker = null;
    while (state instanceof Blocker || state == PARKED) {
      if (state instanceof Blocker) {
        blocker = (Blocker) state;
      }
      spinCount++;
      if (spinCount > MAX_BUSY_WAIT_SPINS) {
        /*

    if (mockWebServer == null) throw new IllegalStateException();

    ByteString state = randomToken();
    synchronized (this) {
      listeners.put(state, listener);
    }

    return slackApi.authorizeUrl(scopes, redirectUrl(), state, team);
  }

  private ByteString randomToken() {
    byte[] bytes = new byte[16];
    secureRandom.nextBytes(bytes);

              + this
              + " to reach a terminal state. "
              + "Current state: "
              + state());
    }
  }

  /** Checks that the current state is equal to the expected state. */
  @GuardedBy("monitor")
  private void checkCurrentState(State expected) {
    State actual = state();
    if (actual != expected) {
      if (actual == FAILED) {

    assertEquals(Service.State.RUNNING, service.state());

    exitRun.countDown(); // the service will exit voluntarily
    executionThread.join();

    assertTrue(service.shutDownCalled);
    assertEquals(Service.State.TERMINATED, service.state());

    service.stopAsync().awaitTerminated(); // no-op
    assertEquals(Service.State.TERMINATED, service.state());
    assertTrue(service.shutDownCalled);
  }

    // Fail fast on a null. We throw NPE here because the contract of Executor states that it throws
    // NPE on null listener, so we propagate that contract up into the add method as well.
    checkNotNull(runnable, "Runnable was null.");
    checkNotNull(executor, "Executor was null.");

    // Lock while we check state. We must maintain the lock while adding the new pair so that