* execute}.
 */
@GwtCompatible
enum DirectExecutor implements Executor {
  INSTANCE;

  @Override
  public void execute(Runnable command) {
    command.run();
  }

  @Override
  public String toString() {
    return "MoreExecutors.directExecutor()";
  }

            }
          }
        };
    addCallback(f, callback, directExecutor());
    f.cancel(true);
  }

  public void testThrowErrorFromGet() {
    Error error = new AssertionError("ASSERT!");
    ListenableFuture<String> f = UncheckedThrowingFuture.throwingError(error);
    MockCallback callback = new MockCallback(error);
    addCallback(f, callback, directExecutor());
  }

  public void testRuntimeExceptionFromGet() {

    @Override
    public void run() {
      countDownLatch.countDown();
    }
  }

  public void testExceptionsCaught() {
    list.add(THROWING_RUNNABLE, directExecutor());
    list.execute();
    list.add(THROWING_RUNNABLE, directExecutor());
  }

  public void testNulls() {
    new NullPointerTester().testAllPublicInstanceMethods(new ExecutionList());
  }

    ClosingFuture<String> willCloseCloseable =
        ClosingFuture.submit(
            closer -> {
              closer.eventuallyClose(closeable, directExecutor());
              return "";
            },
            directExecutor());
    return new WeakReference<>(willCloseCloseable);
  }

    ClosingFuture<String> willCloseCloseable =
        ClosingFuture.submit(
            closer -> {
              closer.eventuallyClose(closeable, directExecutor());
              return "";
            },
            directExecutor());
    return new WeakReference<>(willCloseCloseable);
  }

            }
          }
        };
    addCallback(f, callback, directExecutor());
    f.cancel(true);
  }

  public void testThrowErrorFromGet() {
    Error error = new AssertionError("ASSERT!");
    ListenableFuture<String> f = UncheckedThrowingFuture.throwingError(error);
    MockCallback callback = new MockCallback(error);
    addCallback(f, callback, directExecutor());
  }

  public void testRuntimeExceptionFromGet() {

   * thrown by {@linkplain MoreExecutors#directExecutor direct execution}) will be caught and
   * logged.
   *
   * <p>Note: If your listener is lightweight -- and will not cause stack overflow by completing
   * more futures or adding more {@code directExecutor()} listeners inline -- consider {@link
   * MoreExecutors#directExecutor}. Otherwise, avoid it: See the warnings on the docs for {@code

    @Override
    public void run() {
      countDownLatch.countDown();
    }
  }

  public void testExceptionsCaught() {
    list.add(THROWING_RUNNABLE, directExecutor());
    list.execute();
    list.add(THROWING_RUNNABLE, directExecutor());
  }

  public void testNulls() {
    new NullPointerTester().testAllPublicInstanceMethods(new ExecutionList());
  }

            .catching(Throwable.class, Object::getClass, directExecutor());
    assertThat(f.get()).isEqualTo(CustomRuntimeException.class);
  }

  public void testCatchingAsync() throws Exception {
    FluentFuture<?> f =
        FluentFuture.from(immediateFailedFuture(new CustomRuntimeException()))
            .catchingAsync(Throwable.class, t -> immediateFuture(t.getClass()), directExecutor());

    queue.addListener(listener1, directExecutor());

    Multiset<Object> counters = ConcurrentHashMultiset.create();
    queue.enqueue(incrementingEvent(counters, listener1, 1));
    queue.enqueue(incrementingEvent(counters, listener1, 2));

    Object listener2 = new Object();
    queue.addListener(listener2, directExecutor());