vaadin request wrapped session lose it's value

Vaadin 6 / 7 / 8
1

Hello everybody,

at the moment i’m trying to fix an Bug at the rights management. At the begin of the vaadin page the Wrapped Session has allways a value. When the admin press change user (to check the permission of it) rarely the getWrappedSession function returns null:

request.getWrappedSession().setAttribute("olduser", user); request.getWrappedSession().setAttribute("user", newuser); I allways call getWrappedSession at the start. So the variable should has an value.

Is this problem known?

I’m looking forward to help.

Daniel