Hey, One of the key DDD concepts is that of a Repository, meaning, a place where you can get lookup existing entities either by id or by query. A Repository can also include methods for calculating numbers that are relevant to the collection as a whole, such as "Average salary of all Employees" in the case of a EmployeeRepository.
In Qi4j most such things are placed in the UnitOfWork, since that is always the "scope" of entities. If a client asks for a particular entity twice it will get the same if the same UoW is asked, and different if different UoW's are invoked. So, there is currently no framework support for Repositories. One question is whether we should add this, and move over the find/get/query methods to it, or whether creating Repositories is strictly something that the domain developer does on his own, internally delegating to UoW's. One of the main problems with having a generic Repository is that we can't have domain-specific methods in it, such as the average salary outlined above. Same goes for queries, which will be more generic rather than specific. It might however be an option to have a base interface, and then allow extensions to it for domain specific methods. I don't know what is best. Anyone have thoughts on this? /Rickard _______________________________________________ qi4j-dev mailing list [email protected] http://lists.ops4j.org/mailman/listinfo/qi4j-dev
