Spring Roo is a toolchain for rapid development of Java application using all, some or none of those technologies:
- Spring
- Spring MVC
- Spring Security
- Spring Web Flow
- AspectJ
- JPA (Hibernate, EclipseLink, TopLink)
- JMS (ActiveMQ, etc.)
- GWT
- JSPX
- JSON
- etc.
If you have developped applications with Rails, you will find this application stack oddly familiar, but applied to the Java language. Please note that Roo is not an abstraction layer for those technologies, it is an integration toolchain so that a lot of the boiler-plate is generated for you using some clever part of AspectJ and said technologies.
FYI, I have not affiliated with Spring Roo, I’m making a proof-of-concept built around it.