Advanced Domain Models in Grails: Enterprise Integration Made Easy

Have you seen someone develop a Rails or Grails application in a matter of minutes, only to later discover that their domain model and database schema followed conventions that are different from your existing systems? Or perhaps you're interested in using Grails, but you don't want to duplicate your existing Java domain classes in Groovy. In this session, we'll see how Grails makes it easy to hook into your pre-defined schemas or existing entity classes, while still getting all the rapid application development (RAD) goodness that Grails has to offer.

In an enterprise environment, you're no doubt surrounded by legacy schemas that pre-date Grails by many years, possibly even a decade or so. You want to develop web applications quickly with one of the next-gen frameworks, but there's no chance that management will agree to change all the schemas just so you can code your app using the conventions employed by the next big thing. However, we'll see that with a bit of Hibernate XML or annotations, we can easily wire together our Grails domain models to our existing schema and still get most of the RAD benefits of Grails, including the super-productive dynamic finders. We'll discuss how to deal with various relationship types, non-trivial primary keys, and other database-related challenges.

In another big business scenario, you may find that you already have EJB3 entity beans lying around, perhaps powering some back-end B2B applications. The time has come to build a web front-end for those applications, and you logically want to reuse your current domain classes. With a few simple steps, we'll see how to use those entity beans as your Grails domain classes, and how your EJB3 domain models suddenly get all the benefits of Grails scaffolding, highly-configurable validation rules, powerful Hibernate criteria builders, and more.