Blackboard Duplicate Registration Exception

When i restarted the application then I got DuplicateRegistrationException. Can you tell me how can we handle this exception?

The DRE comes when you try to register a Listener or Event that you already have registered once. So, this sounds like you have a more global instance of Blackboard, and you register listeners and/or events in Application.init(), or something similar. You should register your events and listeners only once per Blackboard instance. The best place to register them would be very near to where you call “new Blackboard()”.

Remember that registering events and listeners is a different thing than adding listeners to Blackboard itself.

Blackboard is exactly what I was looking for! Thanks!

I am running into this same issue when I try to load my app on 2 different browsers. I keep getting:

javax.servlet.ServletException: com.github.wolfie.blackboard.exception.DuplicateRegistrationException

Where would be the best place to instantiate Blackboard and do the registrations? I am doing it in my main view but I am still getting this issue. I have many classes in my application that would all need to fire events on the same Blackboard so my instance is static.