listener.cpp is identical to the listener used for the direct exchange example—it simply reads messages from the message queue. Here is the listener class for this program:

      
class Listener : public MessageListener{
  private:
    SubscriptionManager& subscriptions;
  public:
    Listener(SubscriptionManager& subscriptions);
    virtual void received(Message& message);
};

Listener::Listener(SubscriptionManager& subs) : subscriptions(subs)
{}

void Listener::received(Message& message) {
  std::cout << "Message: " << message.getData() << std::endl;
  if (message.getHeaders().getString("control") == "end") {
      std::cout << "Shutting down listener for " << message.getDestination()
                << std::endl;
      subscriptions.cancel(message.getDestination());
  }
}

And here is the main body of the program:

SubscriptionManager subscriptions(session);

// Create a listener and subscribe it to the queue named "message_queue"
Listener listener(subscriptions);
subscriptions.subscribe(listener, "message_queue");

// Deliver messages until the subscription is cancelled
// by Listener::received()
subscriptions.run();