this.rankMap = rankMap;
  }

  @Override
  public int compare(T left, T right) {
    return rank(left) - rank(right); // safe because both are nonnegative
  }

  private int rank(T value) {
    Integer rank = rankMap.get(value);
    if (rank == null) {
      throw new IncomparableValueException(value);
    }
    return rank;
  }

  @Override
  public boolean equals(@CheckForNull Object object) {

            directExecutor());

    // Wait for the first task to be started in the background. It will block until we explicitly
    // stop it.
    blockingCallable.waitForStart();

    // Give the second task a chance to (incorrectly) start up while the first task is running.
    assertThat(future2.isDone()).isFalse();

    // Stop the first task. The second task should then run.
    blockingCallable.stop();

            directExecutor());

    // Wait for the first task to be started in the background. It will block until we explicitly
    // stop it.
    blockingCallable.waitForStart();

    // Give the second task a chance to (incorrectly) start up while the first task is running.
    assertThat(future2.isDone()).isFalse();

    // Stop the first task. The second task should then run.
    blockingCallable.stop();

            task.setGroup("release notes");
            task.setDescription("Generate release notes HTML page from Markdown.");

            task.getInputEncoding().convention(Charset.defaultCharset().name());
            task.getOutputEncoding().convention(Charset.defaultCharset().name());

    return delegate().submit(task);
  }

  @Override
  public ListenableFuture<?> submit(Runnable task) {
    return delegate().submit(task);
  }

  @Override
  public <T extends @Nullable Object> ListenableFuture<T> submit(
      Runnable task, @ParametricNullness T result) {
    return delegate().submit(task, result);
  }

  public void testNoOpScheduledExecutor() throws InterruptedException {
    taskDone = false;
    Runnable task =
        new Runnable() {
          @Override
          public void run() {
            taskDone = true;
          }
        };
    ScheduledFuture<?> future =
        TestingExecutors.noOpScheduledExecutor().schedule(task, 10, TimeUnit.MILLISECONDS);
    Thread.sleep(20);
    assertFalse(taskDone);

public final class InterruptibleTaskTest extends TestCase {

  // Regression test for a deadlock where a task could be stuck busy waiting for the task to
  // transition to DONE
  public void testInterruptThrows() throws Exception {
    final CountDownLatch isInterruptibleRegistered = new CountDownLatch(1);
    InterruptibleTask<@Nullable Void> task =
        new InterruptibleTask<@Nullable Void>() {
          @Override

       *   user task -- which means that we already got past this code (or else we exited early
       *   above))
       */
      // Unconditionally set; there is no risk of throwing away a queued task from another thread,
      // because in order for the current task to run on this executor the previous task must have
      // already started execution. Because each task on a TaskNonReentrantExecutor can only produce

                final Tuple3<String, String, String> task = generator.createTask(path, docMap);
                if (task != null) {
                    if (logger.isDebugEnabled()) {
                        logger.debug("Add thumbnail task: {}", task);
                    }
                    if (!thumbnailTaskQueue.offer(task)) {
                        logger.warn("Failed to add thumbnail task: {}", task);
                    }

  public void testNoOpScheduledExecutor() throws InterruptedException {
    taskDone = false;
    Runnable task =
        new Runnable() {
          @Override
          public void run() {
            taskDone = true;
          }
        };
    ScheduledFuture<?> future =
        TestingExecutors.noOpScheduledExecutor().schedule(task, 10, TimeUnit.MILLISECONDS);
    Thread.sleep(20);
    assertFalse(taskDone);