assertTrue(limiter.tryAcquire(0, SECONDS));
    assertFalse(limiter.tryAcquire(0, SECONDS));
    assertFalse(limiter.tryAcquire(0, SECONDS));
    stopwatch.sleepMillis(100);
    assertFalse(limiter.tryAcquire(0, SECONDS));
  }

  public void testTryAcquire_someWaitAllowed() {
    RateLimiter limiter = RateLimiter.create(5.0, stopwatch);
    assertTrue(limiter.tryAcquire(0, SECONDS));

    assertTrue(limiter.tryAcquire(0, SECONDS));
    assertFalse(limiter.tryAcquire(0, SECONDS));
    assertFalse(limiter.tryAcquire(0, SECONDS));
    stopwatch.sleepMillis(100);
    assertFalse(limiter.tryAcquire(0, SECONDS));
  }

  public void testTryAcquire_someWaitAllowed() {
    RateLimiter limiter = RateLimiter.create(5.0, stopwatch);
    assertTrue(limiter.tryAcquire(0, SECONDS));

    exec.execute(task);
    runLatch.await();
    taskLatch.countDown();

    ExecutionException e = assertThrows(ExecutionException.class, () -> task.get(5, SECONDS));
    assertEquals(IllegalStateException.class, e.getCause().getClass());

    assertTrue(listenerLatch.await(5, SECONDS));
    assertTrue(task.isDone());
    assertFalse(task.isCancelled());
  }

  public void testListenerCalledOnCancelFromNotRunning() throws Exception {

    exec.execute(task);
    runLatch.await();
    taskLatch.countDown();

    ExecutionException e = assertThrows(ExecutionException.class, () -> task.get(5, SECONDS));
    assertEquals(IllegalStateException.class, e.getCause().getClass());

    assertTrue(listenerLatch.await(5, SECONDS));
    assertTrue(task.isDone());
    assertFalse(task.isCancelled());
  }

  public void testListenerCalledOnCancelFromNotRunning() throws Exception {

    //      last modified: 105 seconds ago
    //             served:   5 seconds ago
    //   default lifetime: (105 - 5) / 10 = 10 seconds
    //            expires:  10 seconds from served date = 5 seconds from now
    server.enqueue(
      MockResponse
        .Builder()
        .addHeader("Last-Modified: " + formatDate(-105, TimeUnit.SECONDS))
        .addHeader("Date: " + formatDate(-5, TimeUnit.SECONDS))

    assertTrue(latch.await(5, SECONDS));
    assertTrue(future.isDone());
    assertFalse(future.isCancelled());

    assertEquals(expectedValue, future.get());
  }

  public void testCancelledFuture() throws InterruptedException, ExecutionException {
    assertTrue(future.isDone());
    assertTrue(future.isCancelled());

    assertTrue(latch.await(5, SECONDS));
    assertTrue(future.isDone());

        assertTrue(addresses.length > 0, "Should return at least one address");
    }

    @Test
    @DisplayName("Should handle NetBIOS name resolution with timeout")
    @Timeout(value = 2, unit = TimeUnit.SECONDS) // Force test timeout
    void testGetNbtByName() {
        // When/Then - Should throw UnknownHostException quickly due to short timeouts
        UnknownHostException exception = assertThrows(UnknownHostException.class, () -> {

    mock.assertLastMethodCalled("scheduleRunnable", 10, MINUTES);

    Future<?> unused2 = testExecutor.schedule(callable(DO_NOTHING), 5, SECONDS);
    mock.assertLastMethodCalled("scheduleCallable", 5, SECONDS);
  }

  public void testSchedule_repeating() {
    MockExecutor mock = new MockExecutor();
    TestExecutor testExecutor = new TestExecutor(mock);

        WitnessRegistration registration =
                client.registerForNotifications("\\\\server\\share", serverAddress, listener).get(5, TimeUnit.SECONDS);

        assertEquals(1, client.getActiveRegistrationCount());

        // Unregister
        client.unregister(registration).get(5, TimeUnit.SECONDS);

        assertEquals(0, client.getActiveRegistrationCount());

        verify(mockRpc).register(any(WitnessRegisterRequest.class));

    // Polling and backoff constants (in ms)
    private static final long MAX_POLL_INTERVAL = 5000; // Normal polling: max 5 seconds
    private static final long MAX_ERROR_BACKOFF = 30000; // Error polling: max 30 seconds
    private static final long BASE_POLL_INTERVAL = 1000;
    private static final long BASE_ERROR_DELAY = 1000;