1 Reply Latest reply on Jan 21, 2015 5:06 PM by Divya Dadlani

    STRANGE : Exception caught: no subscribers to deliver to for subject.

    Jimmy Pannier Newbie


      i follow the documentation for the messaging service but i've an error when i'm using it :



      Here the example used for the test.

      In my entrypoint, i'm just adding a button to deliver a message "hi there" via a service MyEchoService to all users connected


      But when i click it , i get the following error in browser console:

      Exception caught: no subscribers to deliver to for subject: MyEchoService.


      <!- click to the button to call the myechoservice, and my echo service sends message to all users-->
       verticalPanel.add(new UiButton("call myechoservice", new ClickHandler() {
            public void onClick(ClickEvent event) {
              MessageBuilder.createMessage().toSubject("MyEchoService") // (1)
                  .signalling() // (2)
                  .noErrorHandling() // (3)
                  .sendNowWith(ErraiBus.get()); // (4)
      <!-- Listen the subject -->
        ErraiBus.get().subscribe("test", new MessageCallback() {
            public void callback(Message message) {
              String messageText = message.get(String.class, "text");


      public class MyEchoService extends HttpServlet implements MessageCallback {
        private MessageBus bus;
        public MyEchoService(MessageBus messageBus) {
          this.bus = messageBus;
        public void callback(Message message) {
        public void test() {
          MessageBuilder.createMessage().toSubject("test").signalling().with("text", "Hi There").noErrorHandling().sendGlobalWith(bus);
        protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {


      I'm using the last version of wildfly. When i deploy i see the discoverd "myechoservice"


      10:47:49,247 INFO  [org.jboss.errai.cdi.server.CDIExtensionPoints] (MSC service thread 1-15) discovered errai service: [BackedAnnotatedType] public @Service @WebServlet class com.inovelan.cloud.portailps.server.MyEchoService



      If a call the servlet via doGet() of the servlet /MyEchoService The window.alert works !



      SO. Sending message from the client to the server doesn't work but sending message from server to client work.


      I've searched what the problem many days but i don't find the solution.


      Any Idea ?