*       SHORT is always discriminable from zero time, and always allows enough time for the small
 *       amounts of computation (creating a thread, calling a few methods, etc) needed to reach a
 *       timeout point. Similarly, a SMALL is always discriminable as larger than SHORT and smaller
 *       than MEDIUM. And so on. These constants are set to conservative values, but even so, if

      // even check the guard. I don't think we care too much about this use case but it could lead
      // to a confusing error message.
      throw new TimeoutException("Timed out waiting for " + this + " to reach the RUNNING state.");
    }
  }

  @Override
  public final void awaitTerminated() {
    monitor.enterWhenUninterruptibly(isStopped);
    try {
      checkCurrentState(TERMINATED);
    } finally {

        assertThrows(
            TimeoutException.class, () -> service.startAsync().awaitRunning(1, MILLISECONDS));
    assertThat(e)
        .hasMessageThat()
        .isEqualTo("Timed out waiting for Foo [STARTING] to reach the RUNNING state.");
  }

  private class TestService extends AbstractScheduledService {
    CyclicBarrier runFirstBarrier = new CyclicBarrier(2);
    CyclicBarrier runSecondBarrier = new CyclicBarrier(2);

      // should never reach here!
      throw new UnsupportedOperationException();
    }

    @Override
    public Entry<K, V> belowSamplesGreater() {
      // should never reach here!
      throw new UnsupportedOperationException();
    }

    @Override
    public Entry<K, V> aboveSamplesLesser() {
      // should never reach here!
      throw new UnsupportedOperationException();

  }

  /**
   * Waits for the all the services to reach a terminal state. After this method returns all
   * services will either be {@linkplain Service.State#TERMINATED terminated} or {@linkplain
   * Service.State#FAILED failed}.
   */
  public void awaitStopped() {
    state.awaitStopped();
  }

  /**
   * Waits for the all the services to reach a terminal state for no more than the given time. After

            TimeoutException.class,
            () -> service.startAsync().awaitRunning(1, TimeUnit.MILLISECONDS));
    assertThat(e)
        .hasMessageThat()
        .isEqualTo("Timed out waiting for Foo [STARTING] to reach the RUNNING state.");
  }

  private static class TestService extends AbstractIdleService {
    int startUpCalled = 0;
    int shutDownCalled = 0;
    final List<State> transitionStates = Lists.newArrayList();

            TimeoutException.class,
            () -> service.startAsync().awaitRunning(1, TimeUnit.MILLISECONDS));
    assertThat(e)
        .hasMessageThat()
        .isEqualTo("Timed out waiting for Foo [STARTING] to reach the RUNNING state.");
  }

  private class FakeService extends AbstractExecutionThreadService implements TearDown {

    private final ExecutorService executor = Executors.newSingleThreadExecutor();

   * than CPUs, supposing that each thread were bound to a CPU,
   * there would exist a perfect hash function mapping threads to
   * slots that eliminates collisions. When we reach capacity, we
   * search for this mapping by randomly varying the hash codes of
   * colliding threads.  Because search is random, and collisions
   * only become known via CAS failures, convergence can be slow,

        assertThrows(
            TimeoutException.class, () -> service.startAsync().awaitRunning(1, MILLISECONDS));
    assertThat(e)
        .hasMessageThat()
        .isEqualTo("Timed out waiting for Foo [STARTING] to reach the RUNNING state.");
  }

  private class TestService extends AbstractScheduledService {
    CyclicBarrier runFirstBarrier = new CyclicBarrier(2);
    CyclicBarrier runSecondBarrier = new CyclicBarrier(2);

    if (waiter.isAlive()) {
      waiter.interrupt();
      fail("awaitTermination failed to trigger after shutdown()");
    }
  }

  /** Wait for the given thread to reach the {@link State#TIMED_WAITING} thread state. */
  void awaitTimedWaiting(Thread thread) {
    while (true) {
      switch (thread.getState()) {
        case BLOCKED:
        case NEW:
        case RUNNABLE: