What is the Factory Method Pattern in C++?

Can you explain the Factory Method Pattern in C++?

Sure! 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.

What are the benefits of using the Factory Method Pattern?

The benefits include promoting loose coupling, enhancing code maintainability, and allowing for easier unit testing by decoupling the instantiation process.

Can you give me a simple code example?

Certainly! Here's a basic example:

class Product {
public:
    virtual void use() = 0;
};

class ConcreteProductA : public Product {
public:
    void use() override { std::cout << "Using Product A"; }
};

class ConcreteProductB : public Product {
public:
    void use() override { std::cout << "Using Product B"; }
};

class Creator {
public:
    virtual Product* factoryMethod() = 0;
};

class ConcreteCreatorA : public Creator {
public:
    Product* factoryMethod() override { return new ConcreteProductA(); }
};

class ConcreteCreatorB : public Creator {
public:
    Product* factoryMethod() override { return new ConcreteProductB(); }
};

This code defines a Creator class that uses the Factory Method to create products.

How does this pattern compare to other creational patterns?

The Factory Method Pattern is more flexible than the Simple Factory Pattern, as it allows subclasses to decide which class to instantiate. However, it can be more complex than the Singleton Pattern, which restricts instantiation to a single instance.