Prototype Pattern

简化对象的创建过程。

// prototype
class Animal
{
public:
    Animal() = default;
    virtual ~Animal() = default;

    virtual Animal *clone() = 0;
    virtual void play() = 0;
};

// concrete prototype
class Dog : public Animal
{
public:
    Dog() {}
    ~Dog() override {}

    Animal *clone() override
    {
        Dog *dog = new Dog();             // 创建对象
        strncpy(dog->m_name, m_name, 32); // 深拷贝成员变量
        return dog;
    }
    void play() override
    {
        // play
    }

private:
    char m_name[32];
};

class Cat : public Animal
{
public:
    Cat() {}
    ~Cat() override {}

    Animal *clone() override
    {
        Cat *cat = new Cat();
        strncpy(cat->m_name, m_name, 32);
        return cat;
    }
    void play() override
    {
        // play
    }

private:
    char m_name[32];
};

#include "animal.h"

int main(int argc, char *argv[])
{
    Dog *dog = new Dog();
    Cat *cat = new Cat();

    Animal *animal1 = dog->clone();
    Animal *animal2 = cat->clone();

    animal1->play();
    animal2->play();

    return 0;
}

• C++设计模式：原型模式（详解+实现案例）