Project layout violates Vaadin rules

[envas]

Looking at the project layout I see a Vaadin design rules violations.

The code from client package is referenced by the non-client code. For example fi.jasoft.dragdroplayouts.client.ui.Constants are referenced from server side code. It means, the client binary must be deployed as part of the jar file on the server, although it should be only deployed as the javascript compiled by GWT.

Clean designed AddOn should the source code split between the client, shared, and the server side parts. Have a look at the Vaadin sources. Proper design is important for deployments on the servers with limited resources.