Open Multiples tabs

“java.lang.IllegalStateException: UI id has already been defined” when open new tab on integrate Vaadin with JEE6. Why?

Because of @SessionScoped - it refers to an HTTP session which can have multiple UIs.
You try to reuse the same instance of the UI for all tabs, which won’t work.


I tried to reproduce this wiki “”.
I removed the @SessionScope, but occurred the same error.