### Question:
FutureUtils { public static ConjunctFuture<Void> waitForAll(Collection<? extends CompletableFuture<?>> futures) { checkNotNull(futures, "futures"); return new WaitingConjunctFuture(futures); }  static CompletableFuture<T> retry(
			final Supplier<CompletableFuture<T>> operation,
			final int retries,
			final Executor executor); static CompletableFuture<T> retryWithDelay(
			final Supplier<CompletableFuture<T>> operation,
			final int retries,
			final Time retryDelay,
			final Predicate<Throwable> retryPredicate,
			final ScheduledExecutor scheduledExecutor); static CompletableFuture<T> retryWithDelay(
			final Supplier<CompletableFuture<T>> operation,
			final int retries,
			final Time retryDelay,
			final ScheduledExecutor scheduledExecutor); static CompletableFuture<T> retrySuccesfulWithDelay(
		final Supplier<CompletableFuture<T>> operation,
		final Time retryDelay,
		final Deadline deadline,
		final Predicate<T> acceptancePredicate,
		final ScheduledExecutor scheduledExecutor); static CompletableFuture<T> orTimeout(CompletableFuture<T> future, long timeout, TimeUnit timeUnit); static CompletableFuture<Void> runAfterwards(CompletableFuture<?> future, RunnableWithException runnable); static CompletableFuture<Void> runAfterwardsAsync(CompletableFuture<?> future, RunnableWithException runnable); static CompletableFuture<Void> runAfterwardsAsync(
		CompletableFuture<?> future,
		RunnableWithException runnable,
		Executor executor); static CompletableFuture<Void> composeAfterwards(
			CompletableFuture<?> future,
			Supplier<CompletableFuture<?>> composedAction); static ConjunctFuture<Collection<T>> combineAll(Collection<? extends CompletableFuture<? extends T>> futures); static ConjunctFuture<Void> waitForAll(Collection<? extends CompletableFuture<?>> futures); static ConjunctFuture<Void> completeAll(Collection<? extends CompletableFuture<?>> futuresToComplete); static CompletableFuture<T> completedExceptionally(Throwable cause); static CompletableFuture<T> supplyAsync(SupplierWithException<T, ?> supplier, Executor executor); static FiniteDuration toFiniteDuration(Time time); static Time toTime(FiniteDuration finiteDuration); static CompletableFuture<T> toJava(Future<T> scalaFuture);  }### Answer:
@Test public void testCancelWaitingConjunctFuture() { cancelConjunctFuture(inputFutures -> FutureUtils.waitForAll(inputFutures)); }