C++中的工厂方法模式实现:作用域,指针与引用

#include<iostream>
#include<memory>

class Product {
public:
    virtual ~Product() = default;
};

class ConcreteProductA : public Product {
public:
    void print() {
        std::cout << "ConcreteProductA"<< std::endl;
    }
};

class ConcreteProductB : public Product {
public:
    void print() {
        std::cout << "ConcreteProductB"<< std::endl;
    }
};

class Creator {
public:
    virtual ~Creator() = default;
    virtual std::unique_ptr<Product> factoryMethod() = 0;
};

class ConcreteCreatorA : public Creator {
public:
    std::unique_ptr<Product> factoryMethod() override {
        return std::make_unique<ConcreteProductA>();
    }
};

class ConcreteCreatorB : public Creator {
public:
    std::unique_ptr<Product> factoryMethod() override {
        return std::make_unique<ConcreteProductB>();
    }
};

int main() {
    std::unique_ptr<Creator> creatorA = std::make_unique<ConcreteCreatorA>();
    std::unique_ptr<Product> productA = creatorA->factoryMethod();
    productA->print();

    std::unique_ptr<Creator> creatorB = std::make_unique<ConcreteCreatorB>();
    std::unique_ptr<Product> productB = creatorB->factoryMethod();
    productB->print();

    return 0;
}