Customizable Form in Vaadin possible?

Hi everyone,

We use Vaadin framework to display some web forms.

Now we have received the request, that web forms to be customizable:

The user would like to drag&drom the fields in that forms, add the user defined fields, change the layout of the forms add the user defined tabs etc.

Is it possible to realize that request by using Vaadin framework only??

How difficult it is to realize that?