With this add-on you can embed Vaadin UIs into any Vaadin layout.
Suppose you have a Vaadin application running at http://test.com. With this add-on you can add this Vaadin application into another one:
VaadinUIComponent externalUI =
new VaadinUIComponent("http://test.com");
someLayout.addComponent(externalUI);
You can embed multiple Vaadin applications if they all use the same theme and same Vaadin version.
If your Vaadin apps are hosted in different servers. You have to activate HTTP access control (CORS). In your host Vaadin application you can add the provided CorsSessionListener or manually add a CorsBootstrapListener (also provided). In the hosted or embedded applications, you can use any available CORS filter. Spring also supports CORS.
If your Vaadin applications are hosted on the same server (machine), you have to configure different session cookie names for each server.