c++工厂方法模式

1.工厂方法模式简介

   工厂方法模式定义一个用于创建对象的接口，让子类决定实例化哪一个类。工厂方法使一个类的实例化延迟到其子类。

2.源码实现

#include <iostream>
#include <string>

using namespace std;

//车类
class Car
{
public:
    virtual ~Car(){}
    virtual void createCar(void) = 0;
};

//奔驰车
class BenzCar : public Car
{
public:
    BenzCar()
    {
        cout << "Benz::Benz()" << endl;
    }

    virtual ~BenzCar(){}

    virtual void createCar(void)
    {
        cout << "BenzCar::createCar()" << endl;
    }
};

//宝马车
class BmwCar : public Car
{
public:
    BmwCar()
    {
        cout << "Bmw::Bmw()" << endl;
    }

    virtual ~BmwCar(){}

    virtual void createCar(void)
    {
        cout << "BmwCar::createCar()" << endl;
    }
};

//车工厂
class Factory
{
public:
    virtual ~Factory(){}
    virtual Car *createSpecificCar(void) = 0;
};

//奔驰车厂
class BenzFactory : public Factory
{
public:
    virtual ~BenzFactory(){}

    virtual Car *createSpecificCar(void)
    {
        return (new BenzCar());
    }
};

//宝马车厂
class BmwFactory : public Factory
{
public:
    virtual ~BmwFactory(){}

    virtual Car *createSpecificCar(void)
    {
        return (new BmwCar());
    }
};

int main()
{
    Factory *factoryA = new BenzFactory();
    Car *specificCarA = factoryA->createSpecificCar();

    Factory *factoryB = new BmwFactory();
    Car *specificCarB = factoryB->createSpecificCar();

    delete factoryA;
    delete factoryB;
    delete specificCarA;
    delete specificCarB;

    return 0;
}

3.编译源码

$ g++ -o example example.cpp

4.运行及其结果

$ ./example
Benz::Benz()
Bmw::Bmw()