Maintaining session/user data on redeploy


I am wondering how redploys of Vaadin applications should be handled in general. And more specifically how to enable users with an active session, and possibly also unsaved data, to continue using the application after the redeploy.

After a redeploy, or actually just a restart, this familiar message is displayed to the users:

Session Expired Take note of any unsaved data, and click here or press ESC key to continue.

I´ve been trying to find an answer in this forum and in other places, without success. This must be a common issue among the Vaadin users so I guess there is some best practices around this issue.

  • Is it possible to let a user continue working with the application after a redeply, or is it neccesary to reload the whole application if the changes:
  • does not include any changes to the UI-components?
  • includes some changes to the UI-components?

  • If yes, how could this be solved in a Vaadin-ish way?

Best regards,



You could probably get some answers digging into soon-available 7.6 version :

You can also take a look at third-party products, that helps doing hot-changes :