Factory Method Pattern:
The Factory Method Pattern is a creational design pattern that provides an interface for creating objects in a superclass but allows subclasses to alter the type of objects that will be created. In other words, it is a design that creates objects without specifying the exact class of object that will be created. This is accomplished by creating objects via the factory method. A factory method is usually specified as an interface and implemented by child classes (concrete implementations) or implemented in a base class that can be overridden by derived classes. This pattern is useful when a class cannot anticipate the type of objects it needs to create or when a class wants its subclasses to specify the objects it creates. Breakdown: 1. Product: This is the blueprint the factory method will create that all types of products must follow. It declares the interface that the concrete products must implement. 2. Concrete Product: These are the actual products that the factory creates. They adhere to the blueprint, but each has its own unique implementation. 3. Factory Creator: This is the blueprint for the factories. It creates the "factory method", which factories use to create products. 4. Concrete Product Creator: These are the factories that create products. They follow the creator's blueprint, but they can decide which type of product to create. Consider a cheese factory. Using the Factory Method pattern, you can create a new product (like a new type of cheese) without changing the code that uses the product. All you need to do is add a new cheese factory (Concrete Creator) that creates the new cheese. Let's represent the cheese factory example in Go: