void main() throws Exception {
    try (var subscriptions = new FileSubscriptions()) {
        var controlMailbox = "consoleOut/inbox";
        String textMailbox = null;
        subscriptions.subscribe(controlMailbox);

        while (true) {
            var incoming = subscriptions.take();
            var message = incoming.message();

            if (incoming.mailbox().equals(controlMailbox)
                    && message.type().equals("TOPIC")) {
                if (textMailbox != null)
                    subscriptions.unsubscribe(textMailbox);

                textMailbox = message.value();
                subscriptions.subscribe(textMailbox);
                IO.println("ConsoleOut now listens to " + textMailbox);
            } else if (message.type().equals("TEXT")) {
                IO.println(message.value());
            }
        }
    }
}