What's the difference between VaadinSession and VaadinService

Hi All,

I am just a little bit confused about VaadinSession and VaadinService.
When do I have to use them ?



VaadinService is an abstraction layer for tasks common for both servlets and portlets - it essentially services requests.

VaadinSession is associated with requests belonging to a specific user session - one or more UIs from the same browser.

So, one of the tasks of VaadinService is to associate requests with a VaadinSession and further a UI, and then let it handle them.