*
   * @param listener the listener to run when the computation is complete
   * @param executor the executor to run the listener in
   * @throws RejectedExecutionException if we tried to execute the listener immediately but the
   *     executor rejected it.
   */
  void addListener(Runnable listener, Executor executor);

    executor.shutdown();
    assertTrue(executor.isShutdown());
    assertThrows(RejectedExecutionException.class, () -> executor.submit(doNothingRunnable));
    assertFalse(executor.isTerminated());

    // WAIT #2
    barrier.await(1, TimeUnit.SECONDS);
    assertFalse(executor.awaitTermination(20, TimeUnit.MILLISECONDS));

    // WAIT #3
    barrier.await(1, TimeUnit.SECONDS);

    executor.shutdown();
    assertTrue(executor.isShutdown());
    assertThrows(RejectedExecutionException.class, () -> executor.submit(doNothingRunnable));
    assertFalse(executor.isTerminated());

    // WAIT #2
    barrier.await(1, TimeUnit.SECONDS);
    assertFalse(executor.awaitTermination(20, TimeUnit.MILLISECONDS));

    // WAIT #3
    barrier.await(1, TimeUnit.SECONDS);

    executor.execute(task);
    return task;
  }

  /**
   * Executes {@code runnable} on the specified {@code executor}, returning a {@code Future} that
   * will complete after execution.
   *
   * @throws RejectedExecutionException if the task cannot be scheduled for execution
   * @since 28.2
   */
  public static ListenableFuture<@Nullable Void> submit(Runnable runnable, Executor executor) {

                  + runnable
                  + " with executor "
                  + executor,
              e);
    }
  }

  private static final class RunnableExecutorPair {
    final Runnable runnable;
    final Executor executor;
    @CheckForNull RunnableExecutorPair next;

    RunnableExecutorPair(
        Runnable runnable, Executor executor, @CheckForNull RunnableExecutorPair next) {

    final Executor delegate =
        new Executor() {
          @Override
          public void execute(Runnable task) {
            if (future.set(null)) {
              awaitUninterruptibly(latch);
            }
            throw new RejectedExecutionException();
          }
        };
    final SequentialExecutor executor = new SequentialExecutor(delegate);

      assertEquals(Service.State.STOPPING, state());
      shutdownCalled++;
    }

    @Override
    protected Executor executor() {
      return executor;
    }

    @Override
    public void tearDown() throws Exception {
      executor.shutdown();
    }
  }

    final Executor delegate =
        new Executor() {
          @Override
          public void execute(Runnable task) {
            if (future.set(null)) {
              awaitUninterruptibly(latch);
            }
            throw new RejectedExecutionException();
          }
        };
    final SequentialExecutor executor = new SequentialExecutor(delegate);

      assertEquals(Service.State.STOPPING, state());
      shutdownCalled++;
    }

    @Override
    protected Executor executor() {
      return executor;
    }

    @Override
    public void tearDown() throws Exception {
      executor.shutdown();
    }
  }

   */
  public static <V extends @Nullable Object> ListenableFuture<V> listenInPoolThread(
      Future<V> future, Executor executor) {
    checkNotNull(executor);
    if (future instanceof ListenableFuture) {
      return (ListenableFuture<V>) future;
    }
    return new ListenableFutureAdapter<>(future, executor);
  }

  /**
   * An adapter to turn a {@link Future} into a {@link ListenableFuture}. This will wait on the