+ 50 // for the listeners
                + 50 // for the blocking get threads,
                + 1); // for the main thread
    final ExecutorService executor = Executors.newFixedThreadPool(barrier.getParties());
    final AtomicReference<AbstractFuture<String>> currentFuture = Atomics.newReference();
    final AtomicInteger numSuccessfulSetCalls = new AtomicInteger();
    Callable<@Nullable Void> completeSuccessfullyRunnable =