checkState(state != State.FAILED);
    switch (state) {
      case DONE:
        return false;
      case READY:
        return true;
      default:
    }
    return tryToComputeNext();
  }

  private boolean tryToComputeNext() {
    state = State.FAILED; // temporary pessimism
    next = computeNext();
    if (state != State.DONE) {
      state = State.READY;
      return true;
    }

        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) {
        /*

  static void awaitWaiting(Thread t) {
    while (true) {
      Thread.State state = t.getState();
      switch (state) {
        case RUNNABLE:
        case BLOCKED:
          Thread.yield();
          break;
        case WAITING:
          return;
        default:
          throw new AssertionError("unexpected state: " + state);
      }
    }
  }

            /* This guarantees that we leave in a valid state
             */
            if (state != 0 && state != 3 && state != 4) {
                if (LogStream.level >= 1) {
                    log.println("Invalid state: " + state);
                }
                state = 0;
                thread = null;
            }
        }
    }

    /**
     * Disconnects from the remote endpoint.
     *

    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);

  boolean isRunning();

  /** Returns the lifecycle state of the service. */
  State state();

  /**
   * If the service is {@linkplain State#STARTING starting} or {@linkplain State#RUNNING running},
   * this initiates service shutdown and returns immediately. If the service is {@linkplain
   * State#NEW new}, it is {@linkplain State#TERMINATED terminated} without having been started nor

              + 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) {

    assertThat(manager.servicesByState().keySet()).containsExactly(Service.State.FAILED);
  }

  private static void assertState(
      ServiceManager manager, Service.State state, Service... services) {
    Collection<Service> managerServices = manager.servicesByState().get(state);
    for (Service service : services) {
      assertEquals(service.toString(), state, service.state());

        totalFailures.incrementAndGet();
        lastFailureTime.set(System.currentTimeMillis());

        State current = state.get();

        if (current == State.HALF_OPEN) {
            // Single failure in half-open state reopens the circuit
            if (state.compareAndSet(State.HALF_OPEN, State.OPEN)) {
                stateChangeTime.set(System.currentTimeMillis());
                consecutiveFailures.set(1);