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));

    //      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))

    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 {

    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());

        Map<String, Object> stats = resourceManager.getStatistics();
        assertNotNull(stats);
    }

    @Test
    @DisplayName("Test force cleanup")
    @Timeout(value = 5, unit = TimeUnit.SECONDS)
    void testForceCleanup() {
        TestResource resource1 = new TestResource("cleanup1");
        TestResource resource2 = new TestResource("cleanup2");

        resourceManager.registerResource(resource1);

| `minio_node_drive_reads_per_sec`     | Reads per second on a drive.                             |
| `minio_node_drive_reads_kb_per_sec`  | Kilobytes read per second on a drive.                    |
| `minio_node_drive_reads_await`       | Average time for read requests to be served on a drive.  |
| `minio_node_drive_writes_per_sec`    | Writes per second on a drive.                            |

    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);

  }

  public void testTimeToLive_setTwice() {
    CacheBuilder<Object, Object> builder =
        CacheBuilder.newBuilder().expireAfterWrite(3600, SECONDS);
    assertThrows(IllegalStateException.class, () -> builder.expireAfterWrite(3600, SECONDS));
  }

  @GwtIncompatible // Duration
  public void testTimeToLive_setTwice_duration() {
    CacheBuilder<Object, Object> builder =