title: Does this use of Guave EventBus can be a performance hit?
body: <p>I just found out about google's event bus (after 1 day of googling "event queue java" "event bus java" and finding only stuff about GUIs).</p>
  
  <p>It seems cool but my problem is : if we want eventbus to be a singleton we have to make all or observers singleton, and that is not possible since I also have a reference to my DataStore in this handlers.</p>
  
  <p>So I choosed to create an eventbus per http request, so I have to register all my handlers for every http request (if my controller choose which event handler to register that would be breaking the whole pattern). </p>
  
  <p>Do you think it might be a problem ? Or registering handlers is really fast and I don't have to worry about it.</p>