With Spring Data JPA all CRUD operations would we accessed by default.
No more DAO impl - the interface of the DAO is now the only artifact that need to be explicitly defined.
Provides automatically generate queries from the method names and much more.
I suggest it would be a good improvements of data layer.
I might work on it if community agrees
In general we will implement all functionality in DAO interfaces. All DAO impl classes would we removed.
Please have a look on Spring Data JPA tutorial to be more familiar.