AccountService.java

@ApplicationScoped
public class AccountService {

  @Inject @Detected Event<Fraud> event;

  public void watchActivity(@Observes AccountActivity activity) {
    Fraud fraud = new Fraud(System.currentTimeMillis());
    event.fire(fraud);
  }
}

AccountServicePubSub.java

@Service @ApplicationScoped
public class AccountServicePubSub implements MessageCallback {

  @Inject RequestDispatcher dispatcher;

  public void callback(Message activity) {
    MessageBuilder.createMessage()
      .toSubject("FraudClientPubSub")
      .signalling()                  
      .with("fraudTimeStamp", System.currentTimeMillis())     
      .noErrorHandling()            
      .sendNowWith(dispatcher);  
    });
  }
}

AccountServiceRPC.java

@Service @ApplicationScoped
public class AccountServiceRPC implements AccountService {

  public Fraud watchActivity(AccountActivity activity) {
    return new Fraud(System.currentTimeMillis());
  }
}

FraudClient.java

public class FraudClient extends LayoutPanel {

  @Inject Event<AccountActivity> event;
  HTML responsePanel;

  public FraudClient() {
    super(new BoxLayout(BoxLayout.Orientation.VERTICAL));
  }

  @PostConstruct
  public void buildUI() {
    Button button = new Button("Create activity", new ClickHandler() {
      public void onClick(ClickEvent clickEvent) {
        event.fire(new AccountActivity());
      }
    });
    responsePanel = new HTML();
    add(button);
    add(responsePanel);
  }

  public void processFraud(@Observes @Detected Fraud fraudEvent) {
    responsePanel.setText("Fraud detected: " + fraudEvent.getTimestamp());
  }
}

FraudClientPubSub.java

public class FraudClientRPC extends LayoutPanel {
  private MessageBus bus = ErraiBus.get();
  HTML responsePanel;
  ...

  @PostConstruct
  public void buildUI() {
    bus.subscribe("BroadcastReceiver", new MessageCallback() {
       public void callback(CommandMessage message) {
         responsePanel.setText("Fraud detected: " + message.get(Long.class, "fraudTimeStamp");
       }
    });
    Button button = new Button("Create activity", new ClickHandler() {
      public void onClick(ClickEvent clickEvent) {
        MessageBuilder.createMessage()
          .toSubject("AccountServicePubSub")
          .signalling()
          .noErrorHandling()
          .sendNowWith(dispatcher);
      }
    });
    ...
  }
}

FraudClientRPC.java

public class FraudClientRPC extends LayoutPanel {

  @Inject Caller<AccountService> service;
  HTML responsePanel;
  ...

  @PostConstruct
  public void buildUI() {
    Button button = new Button("Create activity", new ClickHandler() {
      public void onClick(ClickEvent clickEvent) {
        service.call(new RemoteCallback<Fraud>() {
          public void callback(Fraud fraud) {
            responsePanel.setText("Fraud detected: " + fraudEvent.getTimestamp());
          }
        }).watchActivity(new AccountActivity());
      }
    });
    ...
  }
}