given:
        def incoming = incomingQueue.getChannel(channel).newEndpoint()
        outgoingQueue.dispatch(outgoingMessage)

        when:
        connections.noFurtherConnections()
        def messages = []
        incoming.take(messages)

        then:
        messages.size() == 2
        messages[0] instanceof RejectedMessage
        messages[0].payload == "payload"

        if (stopping) {
            maybeStop();
        }
    }

    /**
     * Called when no further incoming connections will be added.
     */
    public void noFurtherConnections() {
        stopping = true;
        maybeStop();
    }

    private void maybeStop() {
        if (connections.isEmpty()) {
            outgoingQueue.discardQueued();

            lock.unlock();
        }
    }

    /**
     * Signals that no further connections will be added.
     */
    public void noFurtherConnections() {
        lock.lock();
        try {
            connections.noFurtherConnections();
        } finally {
            lock.unlock();
        }
    }

    private void assertRunning(String action) {
        if (state != State.Running) {

                    methodParamClassLoader,
                    argsSerializer)));

        connection = completion.create(serializer);
        hub.addConnection(connection);
        hub.noFurtherConnections();
        completion = null;
    }

    @Override
    public void requestStop() {
        hub.requestStop();
    }

    @Override
    public void stop() {

        BoundedDispatch<String> handler = Mock()

        given:
        hub.addHandler("channel", handler)

        when:
        operation.signal {
            hub.noFurtherConnections()
        }
        thread.blockUntil.notified

        then:
        1 * handler.endStream() >> {
            thread.blockUntil.signal
            instant.notified
        }
        0 * _._