DAOs and ORMs

The discussion that this article on the ServerSide generated reminds me of an article I wrote a little while ago. The original poster gets a bit confused about the problem because he assume the use of an ORM means that you need to use the "Open Session In View" pattern. But if you get by that and read some of the comments, you discover that many people (like me) don't believe that the DAO pattern is necessary when using an ORM solution.

A valid concern about ditching DAOs is the coupling that may happen between your domain objects and your persistence mechanism. But if you like ActiveRecord or Rich Domain Models or Annotations or XDoclet then you've already made the choice of productivity over ultimate framework plugability and should just get over it.

But if the coupling is still nagging you and you're concerned about sprinkling framework API calls throughout your code then maybe you want to consider looking at EJB3. Instead of using the vendor's API (e.g., Hibernate, Toplink, etc.) you can reference standard annotations and classes that are free of implementation specifics. At least that way you've provided some hope of switching out implementations.

In the end, question why you're using the DAO pattern and then ask yourself if you've already done something in your code that has violated that pattern. Think about your use of OpenSessionInView filters or the navigation of lazily instantiated collections in your view layer. Maybe DAO and ORM really don't mix...