@Override
  @CanIgnoreReturnValue
  public boolean cancel(boolean mayInterruptIfRunning) {
    return delegate().cancel(mayInterruptIfRunning);
  }

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

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

  @Override
  @CanIgnoreReturnValue
  @ParametricNullness

  }

  public void testCancel_notDoneNoInterrupt() throws Exception {
    Future<?> future = newFutureInstance();
    assertTrue(future.cancel(false));
    assertTrue(future.isCancelled());
    assertTrue(future.isDone());
    assertThat(tryInternalFastPathGetFailure(future)).isNull();
    CancellationException e = assertThrows(CancellationException.class, future::get);

  }

  public void testCancel_notDoneNoInterrupt() throws Exception {
    Future<?> future = newFutureInstance();
    assertTrue(future.cancel(false));
    assertTrue(future.isCancelled());
    assertTrue(future.isDone());
    assertThat(tryInternalFastPathGetFailure(future)).isNull();
    CancellationException e = assertThrows(CancellationException.class, future::get);

  }

  /**
   * Tests that a canceled future throws a cancellation exception.
   *
   * <p>This method checks the cancel, isCancelled, and isDone methods.
   */
  public void testCanceledFutureThrowsCancellation() throws Exception {

    assertFalse(future.isDone());
    assertFalse(future.isCancelled());

    CountDownLatch successLatch = new CountDownLatch(1);

   * does not include "was cancelled." To be explicit: If this method returns a non-null value,
   * then:
   *
   * <ul>
   *   <li>{@code isDone()} must return {@code true}
   *   <li>{@code isCancelled()} must return {@code false}
   *   <li>{@code get()} must not block, and it must throw an {@code ExecutionException} with the
   *       return value of this method as its cause
   * </ul>
   *

  }

  @Override
  public boolean cancel(boolean mayInterruptIfRunning) {
    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 {

  }

  /**
   * Tests that a canceled future throws a cancellation exception.
   *
   * <p>This method checks the cancel, isCancelled, and isDone methods.
   */
  public void testCanceledFutureThrowsCancellation() throws Exception {

    assertFalse(future.isDone());
    assertFalse(future.isCancelled());

    CountDownLatch successLatch = new CountDownLatch(1);

   * does not include "was cancelled." To be explicit: If this method returns a non-null value,
   * then:
   *
   * <ul>
   *   <li>{@code isDone()} must return {@code true}
   *   <li>{@code isCancelled()} must return {@code false}
   *   <li>{@code get()} must not block, and it must throw an {@code ExecutionException} with the
   *       return value of this method as its cause
   * </ul>
   */
  public static

  }

  @Override
  @ParametricNullness
  public V get(long timeout, TimeUnit unit) throws ExecutionException {
    checkNotNull(unit);
    return get();
  }

  @Override
  public boolean isCancelled() {
    return false;
  }

  @Override
  public boolean isDone() {
    return true;
  }

  @Override
  public String toString() {
    // Behaviour analogous to AbstractFuture#toString().

    @RetainedLocalRef F localFallback = fallback;
    if ((localInputFuture == null | localExceptionType == null | localFallback == null)
        // This check, unlike all the others, is a volatile read
        || isCancelled()) {
      return;
    }
    inputFuture = null;

    // For an explanation of the cases here, see the comments on AbstractTransformFuture.run.
    V sourceResult = null;
    Throwable throwable = null;