Entity / Class Question

[jdavid]

I noticed in the example project that under business domain there are entities such as Account, Shopping Cart, Transaction. Then under the implementation model there are a second set of classes called Account, Shopping Cart, Transaction. The question is why have two seperate objects, why not just create an instance of the entity as a class??

[thomaskilian]

The objects refer to real things found during the analysis phase. Thus the object usage. When you start (re-)designing the system you will no longer work with objects, but classes. There will likely be a relation between both which you can see at the names. You could additionally draw <<trace>> relations between both to emphasise the relation.