设计模式学习1-工厂方法模式

前几天接到吉威时代电话面试，问了一个设计模式的问题，这方面自己只是了解，但不是很熟悉，所以没回答上，于是决定现在开始学习这方面的知识，先从最简单的工厂方法模式开始：

这种模式其实就是新建一个Factory接口，每个产品都有各自的工厂继承自该接口，来生产不同的产品，以水果为例：

#include
class Fruit{
public:Fruit(){};virtual ~Fruit(){};virtual void sayHello(void)=0;virtual void showColor(void)=0;
};
class Apple:public Fruit{
public:Apple(){}~Apple(){}void sayHello(void){std::cout<<"I am apple!"<<std::endl;}void showColor(void){std::cout<<"My color is red!"<<std::endl;}
};
class Banana:public Fruit{
public:Banana(){}~Banana(){}void sayHello(void){std::cout<<"I am banana!"<<std::endl;}void showColor(void){std::cout<<"My color is yellow!"<<std::endl;}
};
class Factory{
public:Factory(){}virtual ~Factory(){}virtual Fruit* createFruit()=0;
};
class AppleFactory:public Factory{
public:AppleFactory(){}~AppleFactory(){}Fruit* createFruit(){return new Apple();}
};
class BananaFactory:public Factory{
public:BananaFactory(){}~BananaFactory(){}Fruit* createFruit(){return new Banana();}
};
int main()
{AppleFactory *af=new AppleFactory();Fruit *apple=af->createFruit();apple->sayHello();apple->showColor();BananaFactory *bf=new BananaFactory();Fruit *banana=bf->createFruit();banana->sayHello();banana->showColor();delete af;delete apple;delete bf;delete banana;return 0;
}