dispatcher = Dispatcher.legacyAsync();

    final CyclicBarrier barrier = new CyclicBarrier(2);
    final CountDownLatch latch = new CountDownLatch(2);

    new Thread(
            new Runnable() {
              @Override
              public void run() {
                try {
                  barrier.await();
                } catch (Exception e) {
                  throw new AssertionError(e);

    if (!Collections.disjoint(newFeatures, earlierFeatures)) {
      throw new ConflictingRequirementsException(
          String.format(
              Locale.ROOT,
              "Annotation requires to be %s features that earlier "
                  + "annotations required to be %s.",
              newRequirement,
              earlierRequirement),
          intersection(newFeatures, earlierFeatures),
          source);
    }
  }

     * jar files' "Class-Path" manifest entries. Particularly, if a jar file from the "Class-Path"
     * manifest entry is already in {@code scannedFiles}, either because it was scanned earlier, or
     * it was intentionally added to the set by the caller, it will not be scanned again.
     *
     * <p>Note that when you call {@code location.scanResources(scannedFiles)}, the location will

  //    (hypothetical) unsafe read by our caller. Note: adding 'volatile' does not fix this issue,
  //    it would just add an edge such that if done() observed non-null, then it would also
  //    definitely observe all earlier writes, but we still have no guarantee that done() would see
  //    the initial write (just stronger guarantees if it does).
  //
  // See: http://cs.oswego.edu/pipermail/concurrency-interest/2015-January/013800.html

    }
    final CyclicBarrier barrier =
        new CyclicBarrier(
            6 // for the setter threads
                + 50 // for the listeners
                + 50 // for the blocking get threads,
                + 1); // for the main thread
    final ExecutorService executor = Executors.newFixedThreadPool(barrier.getParties());

      barrier.await(1, TimeUnit.SECONDS);
      executor.execute(barrierTask);
      // timeout means the second task wasn't even tried
      barrier.await(1, TimeUnit.SECONDS);
    } finally {
      service.shutdown();
    }
  }

  public void testRejectedExecutionThrownWithMultipleCalls() throws Exception {
    final CountDownLatch latch = new CountDownLatch(1);

    dispatcher = Dispatcher.legacyAsync();

    final CyclicBarrier barrier = new CyclicBarrier(2);
    final CountDownLatch latch = new CountDownLatch(2);

    new Thread(
            new Runnable() {
              @Override
              public void run() {
                try {
                  barrier.await();
                } catch (Exception e) {
                  throw new AssertionError(e);

                public @Nullable Void call() throws Exception {
                  barrier.await();
                  Integer first = network.nodes().iterator().next();
                  for (Integer node : network.nodes()) {
                    Set<Integer> unused = network.successors(node);
                  }
                  /*
                   * Also look up an earlier node so that, if the graph is using MapRetrievalCache,

                public @Nullable Void call() throws Exception {
                  barrier.await();
                  Integer first = network.nodes().iterator().next();
                  for (Integer node : network.nodes()) {
                    Set<Integer> unused = network.successors(node);
                  }
                  /*
                   * Also look up an earlier node so that, if the graph is using MapRetrievalCache,

                              barrier.await(1, TimeUnit.SECONDS);

                              // WAIT #2
                              barrier.await(1, TimeUnit.SECONDS);
                              assertTrue(executor.isShutdown());
                              assertFalse(executor.isTerminated());

                              // WAIT #3
                              barrier.await(1, TimeUnit.SECONDS);