07 Oct 2021
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As discussed in another note, we would like to enforce the fact, that only store can create a Dish. Unfortunately it seems, that we cannot really acheive it with only Dish design (i.e. with the design of well-fed-cat-core-components). This can only be enforced by the implementation of a particular store. And because core-components do not controll implementation of particular stores, we can only articulate in the documentation conventions, which have to be maintained by store implementation for he system to work properly.
In particular, we are only interested in Dishes, which are considered in context of DishStore, so if DishStore simply does not provide the possibility to store existing dishes created outside of the store, then those dishes created outside of the store become useless.
It is obvious, that we cannot make constructor of Dish private, because at least DishStore needs to create Dish objects.
At the beginning I has some ideas to fiddle with nested classes or with package-private methods etc, but it all does not work or makes things too cumbersome.
After all if we provide possibility to DishStore to create Dishes, then it can always be used as a jail-break, i.e. one can impleemnt interface with all dummy methods and only one method implemented, which just fast- forwards constructor of the Dish. So further thinking about enforcement of this seems to be non-constructive. We have to just stay with declaring in the documentation requirements to the compliant DishStore implementations and probably providing automated tests, which would at least partially test this compliance.
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