title: Guava EventBus in globally (singleton) and session based in Vaadin with Spring Boot
body: <p>I'm trying to get the Guava <code>EventBus</code> as Singleton and session based in a <code>Vaadin</code> application with spring boot but i cannot get it working so far. The session based one works but not the singleton one.The idea is to implement a global notification service, so that specific users get informed in case of new events. I tried following:</p>
  
  <pre><code>public class Configuration{
  
      @Scope("singleton")
      @Bean
      public EventBus globalEventBus(){
         return new EventBus("globalEventBus");
      }
  
      @SessionScoped
      @Bean
      public EventBus eventBus(){
          return new EventBus();
      }
  }
  </code></pre>