What's the problem?

I run a web application on tomcat in Eclipse.Whenever i modify the source,the Console indicates “Reloading Context with name
[/VaadinDemo] has started”(no end?). No expected effect comes out when refreshing the browser,while it works by manuelly restarting Tomcat.what’s the problem,something wrong with the setting ?

Try to add a ?restartApplication parameter to the URL of your application.

Vaadin’s state is stored in the session, so even though you refresh your browser, the state is preserved. To launch a new application instance (== new session), try adding “?restartApplication” as a parameter to your application’s URL, for example, http://localhost:8080/YourApp?restartApplication