Why does Abstract Factory deal with families, and Factory Method with generating a single object?

Question

From what I have read, the abstract factory pattern typically concerns itself with creating several objects which are all associated with the same family, and the factory me

Answer 1

In the given examples, BasePizzaCreator is an Abstract Factory, but IPizzaFactory is not any GoF design pattern (though it is sometimes referred to as a Simple Factory).

As to why Abstract Factory deals with product families while Factory Method deals with a single product: that's simply how the GoF defined them. The GoF book mentions the most common way to implement an Abstract Factory is with multiple Factory Methods; but I've not seen that in practice. From a client's perspective, Abstract Factory may be preferable because clients invoke it through composition/delegation, as opposed to Factory Method which requires clients to inherit that method.

Finally, note that "Abstract Factory vs. Factory Method" is the second-most popular design patterns topic on Stack Overflow. Unfortunately, there is a lot of (highly-upvoted) misinformation posted as well, so when in doubt, always refer back to the book.

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