New User - Form caching question

I am creating a logon page servlet to be used with jboss. (I realize just a logon page using vaadin might be too heavy weight, but ignore that for now).

The issue I am having is the userid and password field when I enter text into it, then shift-refresh it the userid and password are retained in the field.

In code when the form is instantiated, I have it resetting the fields, but that doesn’t seem to be solving the issue. Any thoughts what this could be?

First of all, you seem to think in a page oriented way. Vaadin isn’t meant to be used as page oriented, Vaadin is intended for making applications rather than pages. What this means in practice, is that once you open a Vaadin application, you should never see the URL changing (except
URI fragments

Vaadin is also statefull and the state is preserved on the server side. This means, that if you type some text to textfields, navigate somewhere else in the application - actually, do anything that modifies the UI in any way, it will look exactly the same even if you refresh your browser, or even if you navigate away from the application and return back later (as long as the session hasn’t expired). This is the behavior you are facing. The fields are not cleared, because that is exactly how Vaadin is designed to work.

I understand that you may not want to have this kind of a behavior on a login page. I suggest you take a look at the
component which works in a bit different way. It actually clears the fields when you refresh your browser.