Ok – today I’ll start by creating a factory for the Product class. I have some issues with the factory pattern and here is my reasoning: Another class is the creator and must have access to the NEW method of the class to create it. Since that forces at least a protected-level on the constructor, it means that I cannot be sure that clients use the factory and not the constructor.
If I place the factory method on the class I am creating, I can ensure this. But then I am violating the Single Responsibility Principle. What to do, what to do…
For now, in TDD/XP fashion, I’ll implement the simplest solution: a static Create method on the class I am creating. I don’t have several different Product types, so it’s the same factory for all products, possibly with overloads.
Flame away, ye flamers, and give me some insight on how I should have done it.
Another problem I faced yesterday was that the product I added to my repository did not show up in the list of all products on the next page. That puzzled me for a while until I realized that, even though I am using the fake in-memory repository version, I am recreating it on each request.
So, I needed some sort of Singleton version of the repository to use for my application until I add support for SQL. I didn’t want to do that just yet…
This turned out to be quite tricky, but I am happy with the result – it was only a few lines of code. Now I have an in-memory repository that remembers actions until I close the application.