Vaadin and Session

Good day, everyone!

If you forget AppFoundation, then:

  1. How to most accurately by using Vaadin applies to standard notions of Session, whether or not access Session at all, or just pure Java server-side developer, then write in the style of desktop applications?

  2. Since the session and Vaadin applications exist, and there is a time of its action, as you can catch the event of termination of the session to transfer the user to a login page or display a notice?

  3. Maybe someone to share their methods for solving these problems, or express his opinion?

Thank you!