Thanks to all participants for the interest and the challenging questions. The slides are in the attachment. Here are answers to the questions I could not answer on forum:
* Spring and JAX-RS - my mistake, Spring does not have it's own implementation. What I saw when I listed it, were different REST solutions implemented with Spring MVC. But such solution is similar to REST with servlets, it's not an implementation of JAX-RS.
* DataSource entity type - it's not related to database, it's javax.activation.DataSource http://lia.deis.unibo.it/Courses/TecnologieWeb0708/materiale/laboratorio/guide/j5eeapi/javax/activation/DataSource.html
Bye!
Andrew.