final AtomicInteger numCalls = new AtomicInteger();
    final AtomicBoolean reject = new AtomicBoolean(true);
    final SequentialExecutor executor =
        new SequentialExecutor(
            new Executor() {
              @Override
              public void execute(Runnable r) {
                if (reject.get()) {
                  throw new RejectedExecutionException();
                }

    final AtomicInteger numCalls = new AtomicInteger();
    final AtomicBoolean reject = new AtomicBoolean(true);
    final SequentialExecutor executor =
        new SequentialExecutor(
            new Executor() {
              @Override
              public void execute(Runnable r) {
                if (reject.get()) {
                  throw new RejectedExecutionException();
                }