Also known as
Define an interface for creating an object, but let subclasses decide which class to instantiate. Factory Method lets a class defer instantiation to subclasses.
Use the Factory Method pattern when
- a class can't anticipate the class of objects it must create
- a class wants its subclasses to specify the objects it creates
- classes delegate responsibility to one of several helper subclasses, and you want to localize the knowledge of which helper subclass is the delegate