// Why 1000?  WHY NOT!
  private static final int MAX_BUSY_WAIT_SPINS = 1000;

  @Override
  public final void run() {
    /*
     * Set runner thread before checking isDone(). If we were to check isDone() first, the task
     * might be cancelled before we set the runner thread. That would make it impossible to
     * interrupt, yet it will still run, since interruptTask will leave the runner value null,

    return delegate.cancel(mayInterruptIfRunning);
  }

  @Override
  public boolean isCancelled() {
    return delegate.isCancelled();
  }

  @Override
  public boolean isDone() {
    return delegate.isDone();
  }

  @Override
  @ParametricNullness
  public V get() throws InterruptedException, ExecutionException {
    return delegate.get();
  }

  @Override
  @ParametricNullness

  }

  public void testCancel_notDoneNoInterrupt() throws Exception {
    Future<?> future = newFutureInstance();
    assertTrue(future.cancel(false));
    assertTrue(future.isCancelled());
    assertTrue(future.isDone());
    assertNull(tryInternalFastPathGetFailure(future));
    CancellationException e = assertThrows(CancellationException.class, () -> future.get());
    assertNotNull(e.getCause());
  }

  }

  public void testCancel_notDoneNoInterrupt() throws Exception {
    Future<?> future = newFutureInstance();
    assertTrue(future.cancel(false));
    assertTrue(future.isCancelled());
    assertTrue(future.isDone());
    assertNull(tryInternalFastPathGetFailure(future));
    CancellationException e = assertThrows(CancellationException.class, () -> future.get());
    assertNotNull(e.getCause());
  }

  // Why 1000?  WHY NOT!
  private static final int MAX_BUSY_WAIT_SPINS = 1000;

  @Override
  public final void run() {
    /*
     * Set runner thread before checking isDone(). If we were to check isDone() first, the task
     * might be cancelled before we set the runner thread. That would make it impossible to
     * interrupt, yet it will still run, since interruptTask will leave the runner value null,

    assertThat(future.isDone()).isFalse();
    assertThat(future.set(1)).isTrue();
    assertSuccessful(future, 1);
  }

  public void testSetFutureNull() throws Exception {
    assertThrows(NullPointerException.class, () -> future.setFuture(null));

    assertThat(future.isDone()).isFalse();
    assertThat(future.set(1)).isTrue();
    assertSuccessful(future, 1);

    private int h1;
    private long buffer;
    private int shift;
    private int length;
    private boolean isDone;

    Murmur3_32Hasher(int seed) {
      this.h1 = seed;
      this.length = 0;
      isDone = false;
    }

    private void update(int nBytes, long update) {
      // 1 <= nBytes <= 4
      buffer |= (update & 0xFFFFFFFFL) << shift;

    return delegate.cancel(mayInterruptIfRunning);
  }

  @Override
  public boolean isCancelled() {
    return delegate.isCancelled();
  }

  @Override
  public boolean isDone() {
    return delegate.isDone();
  }

  @Override
  @ParametricNullness
  public V get() throws InterruptedException, ExecutionException {
    return delegate.get();
  }

  @Override
  @ParametricNullness

   * returned future will emulate {@link ListenableFuture#addListener} by taking a thread from an
   * internal, unbounded pool at the first call to {@code addListener} and holding it until the
   * future is {@linkplain Future#isDone() done}.
   *
   * <p>Prefer to create {@code ListenableFuture} instances with {@link SettableFuture}, {@link
   * MoreExecutors#listeningDecorator( java.util.concurrent.ExecutorService)}, {@link

     */
    @CanIgnoreReturnValue
    @Override
    public V get() throws InterruptedException, ExecutionException {
      return sync.get();
    }

    @Override
    public boolean isDone() {
      return sync.isDone();
    }

    @Override
    public boolean isCancelled() {
      return sync.isCancelled();
    }

    @CanIgnoreReturnValue
    @Override