// unmeasurable (comparing done AbstractFutures with immediateFuture)
    if (obj instanceof Cancellation) {
      Cancellation cancellation = (Cancellation) obj;
      Throwable cause = cancellation.cause;
      throw cancellationExceptionWithCause("Task was cancelled.", cause);
    } else if (obj instanceof Failure) {
      Failure failure = (Failure) obj;

 *
 * <p>This class has limited support for cancellation and other "early completions":
 *
 * <ul>
 *   <li>While calls to {@code submit} and {@code submitAsync} return a {@code Future} that can be
 *       cancelled, cancellation never propagates to a task that has started to run -- neither to
 *       the callable itself nor to any {@code Future} returned by an {@code AsyncCallable}.

     * All elements of `futures` are completed, or this future has already completed and read
     * `futures` into a local variable (in preparation for propagating cancellation to them). In
     * either case, no one needs to read `futures` for cancellation purposes later. (And
     * cancellation purposes are the main reason to access `futures`, as discussed in its docs.)
     */
    this.futures = null;
  }

  enum ReleaseResourcesReason {

 *
 * <p>When chaining together a graph of asynchronous operations, you will often find it easier to
 * use a framework. Frameworks automate the process, often adding features like monitoring,
 * debugging, and cancellation. Examples of frameworks include:
 *
 * <ul>
 *   <li><a href="https://dagger.dev/producers.html">Dagger Producers</a>
 * </ul>
 *

        return getValue();
      }

      /**
       * Implementation of the actual value retrieval. Will return the value on success, an
       * exception on failure, a cancellation on cancellation, or an illegal state if the
       * synchronizer is in an invalid state.
       */
      private V getValue() throws CancellationException, ExecutionException {
        int state = getState();

        return getValue();
      }

      /**
       * Implementation of the actual value retrieval. Will return the value on success, an
       * exception on failure, a cancellation on cancellation, or an illegal state if the
       * synchronizer is in an invalid state.
       */
      private V getValue() throws CancellationException, ExecutionException {
        int state = getState();

    }
    inputFuture = null;

    if (localInputFuture.isCancelled()) {
      @SuppressWarnings("unchecked")
      boolean unused =
          setFuture((ListenableFuture<O>) localInputFuture); // Respects cancellation cause setting
      return;
    }

    /*
     * Any of the setException() calls below can fail if the output Future is cancelled between now

   * Implementations must support such concurrent calls.
   *
   * Note that cancellation is best-effort and that a call may proceed normally after it has been
   * canceled. For example, happy-path events like [requestHeadersStart] and [requestHeadersEnd] may
   * occur after a call is canceled. Typically cancellation takes effect when an expensive I/O
   * operation is required.
   *

    patterns. We also fixed a bug where the cache was being cleared due to a
    corrupted journal. We've added APIs to configure a request's `Cache-Control`
    headers, and to manually clear the cache.

 *  **Request cancellation fixes.** This update fixes a bug where synchronous
    requests couldn't be canceled by tag. This update avoids crashing when
    `onResponse()` throws an `IOException`. That failure will now be logged

       * cycle_suppress_list.txt.
       */
      private final AbstractService service;

      /**
       * This lock is used to ensure safe and correct cancellation, it ensures that a new task is
       * not scheduled while a cancel is ongoing. Also it protects the currentFuture variable to
       * ensure that it is assigned atomically with being scheduled.
       */