Okay, here we go. I’m going to spit out some bullshit and home someone corrects me if I’m wrong. I’ve looked for some explanations and this is what I’ve gotten.
Are you ready?
The Factory Pattern.
My understanding is that the purpose is a function to return any of several types of objects, but a specific type, not just an interface or whatever they might all inherit from.
I think most languages now have something like a “dynamic” keyword to solve this issue by allowing determination of the type only at runtime. (To be used with extreme caution.)
But most of the time I see the Factory pattern, it’s used unnecessarily and can only return one specific type. Why they would use a Factory pattern here and not just a plain old constructor confounds me.
Factory pattern can return a mock type for testing or a production type, as needed, which makes it possible to unit test the code that uses the produced object.
This quick guide explains it well. Then it improves on it by explaining dependency injection.
Yeah most uses of the factory pattern are unnecessary and it’s mild code smell IMO. If your factory only returns one type you should definitely just use that type’s constructor.
Okay, here we go. I’m going to spit out some bullshit and home someone corrects me if I’m wrong. I’ve looked for some explanations and this is what I’ve gotten.
Are you ready?
The Factory Pattern.
My understanding is that the purpose is a function to return any of several types of objects, but a specific type, not just an interface or whatever they might all inherit from.
I think most languages now have something like a “dynamic” keyword to solve this issue by allowing determination of the type only at runtime. (To be used with extreme caution.)
But most of the time I see the Factory pattern, it’s used unnecessarily and can only return one specific type. Why they would use a Factory pattern here and not just a plain old constructor confounds me.
Am I off base?
Factory pattern can return a mock type for testing or a production type, as needed, which makes it possible to unit test the code that uses the produced object.
This quick guide explains it well. Then it improves on it by explaining dependency injection.
https://github.com/google/guice/wiki/Motivation
Yeah most uses of the factory pattern are unnecessary and it’s mild code smell IMO. If your factory only returns one type you should definitely just use that type’s constructor.