We'll refactor this next year anyways

https://programming.dev/post/12679593

We'll refactor this next year anyways - programming.dev

public class AbstractBeanVisitorStrategyFactoryBuilderIteratorAdapterProviderObserverGeneratorDecorator { // boilerplate goes here }

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?

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.

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.

github.com/google/guice/wiki/Motivation

Motivation

Guice (pronounced 'juice') is a lightweight dependency injection framework for Java 11 and above, brought to you by Google. - google/guice

GitHub