@CanIgnoreReturnValue
  protected boolean setFuture(ListenableFuture<? extends V> future) {
    checkNotNull(future);

    // If this future is already cancelled, cancel the delegate.
    // TODO(cpovirk): Should we do this at the end of the method, as in the server version?
    // TODO(cpovirk): Use maybePropagateCancellationTo?
    if (isCancelled()) {
      future.cancel(mayInterruptIfRunning);
    }

          future = setFuture.owner;
          if (future.value == setFuture) {
            Object valueToSet = getFutureValue(setFuture.future);
            if (ATOMIC_HELPER.casValue(future, setFuture, valueToSet)) {
              continue outer;
            }
          }
          // otherwise the future we were trying to set is already done.

          future = setFuture.owner;
          if (future.value == setFuture) {
            Object valueToSet = getFutureValue(setFuture.future);
            if (ATOMIC_HELPER.casValue(future, setFuture, valueToSet)) {
              continue outer;
            }
          }
          // otherwise the future we were trying to set is already done.