assertTrue(writeLockA.tryLock());
    assertTrue(readLockA.tryLock());
  }

  private static class LockingThread extends Thread {
    final CountDownLatch locked = new CountDownLatch(1);
    final CountDownLatch finishLatch = new CountDownLatch(1);
    final Lock lock;

    LockingThread(Lock lock) {
      this.lock = lock;
    }

    @Override
    public void run() {
      lock.lock();

  }

  private static class BlockingCallable implements Callable<@Nullable Void> {
    private final CountDownLatch startLatch = new CountDownLatch(1);
    private final CountDownLatch stopLatch = new CountDownLatch(1);

    private volatile boolean running = false;

    @Override
    public @Nullable Void call() throws InterruptedException {
      running = true;

  }

  private static class BlockingCallable implements Callable<@Nullable Void> {
    private final CountDownLatch startLatch = new CountDownLatch(1);
    private final CountDownLatch stopLatch = new CountDownLatch(1);

    private volatile boolean running = false;

    @Override
    public @Nullable Void call() throws InterruptedException {
      running = true;

    assertThat(dispatcher.queuedCalls())
      .containsExactlyInAnyOrder(a4, a5)
  }

  @Test
  fun synchronousCallAccessors() {
    val ready = CountDownLatch(2)
    val waiting = CountDownLatch(1)
    client =
      client.newBuilder()
        .addInterceptor(
          Interceptor { chain: Interceptor.Chain? ->
            try {
              ready.countDown()

        }

        if (result.getArtifactResolutionNodes() != null) {
            ClassLoader classLoader = Thread.currentThread().getContextClassLoader();

            CountDownLatch latch =
                    new CountDownLatch(result.getArtifactResolutionNodes().size());

            for (ResolutionNode node : result.getArtifactResolutionNodes()) {
                Artifact artifact = node.getArtifact();

    assertEquals(Service.State.FAILED, service.state());
  }

  public void testFailOnErrorFromStartUpListener() throws InterruptedException {
    final Error error = new Error();
    final CountDownLatch latch = new CountDownLatch(1);
    TestService service = new TestService();
    service.addListener(
        new Service.Listener() {
          @Override
          public void running() {
            throw error;

    dns["san.com"] = Dns.SYSTEM.lookup(server.hostName).subList(0, 1)
    val sanUrl = url.newBuilder().host("san.com").build()
    val latch1 = CountDownLatch(1)
    val latch2 = CountDownLatch(1)
    val latch3 = CountDownLatch(1)
    val latch4 = CountDownLatch(1)
    val listener1: EventListener =
      object : EventListener() {
        override fun connectStart(
          call: Call,

   * even permanently blocked.
   */
  public void testListenerDeadlock() throws InterruptedException {
    final CountDownLatch failEnter = new CountDownLatch(1);
    final CountDownLatch failLeave = new CountDownLatch(1);
    final CountDownLatch afterStarted = new CountDownLatch(1);
    Service failRunService =
        new AbstractService() {
          @Override
          protected void doStart() {

    } catch (e: InterruptedException) {
      Thread.currentThread().interrupt()
    }
  }

  private fun cancelLater(
    call: Call,
    delayMillis: Int,
  ): CountDownLatch {
    val latch = CountDownLatch(1)
    Thread {
      sleep(delayMillis)
      if (cancelMode == CANCEL) {
        call.cancel()
      } else {
        threadToCancel!!.interrupt()
      }
      latch.countDown()

  }

  public void testNull() throws Exception {
    new NullPointerTester()
        .setDefault(CountDownLatch.class, new CountDownLatch(0))
        .setDefault(Semaphore.class, new Semaphore(999))
        .testAllPublicStaticMethods(Uninterruptibles.class);
  }

  // IncrementableCountDownLatch.await() tests

  // CountDownLatch.await() tests

  // Condition.await() tests
  public void testConditionAwaitTimeoutExceeded() {