Factory method pattern工厂方法/abstract factory pattern抽象工厂

wiki提供的例子，工厂方法，是对单一产品(button)的异化，而抽象工厂是进一步的工厂方法或者是多个产品组合(工厂级别)的异化。



//几个Button类 class Button{/* ...*/} class WinButton extends Button{/* ...*/} class MacButton extends Button{/* ...*/} //它们的工厂类 interface ButtonFactory{ abstract Button createButton(); } class WinButtonFactory implements ButtonFactory{ Button createButton(){ return new WinButton(); } } class MacButtonFactory implements ButtonFactory{ Button createButton(){ return new MacButton(); } }

class Button; // Abstract Class
 
class MacButton: public Button {};
 
class WinButton: public Button {};
 
class Border; // Abstract Class
 
class MacBorder: public Border {};
 
class WinBorder: public Border {};

对应的工厂是这样的

class AbstractFactory {
public:
    virtual Button* CreateButton() =0;
    virtual Border* CreateBorder() =0;
};
 
class MacFactory: public AbstractFactory {
public:
    MacButton* CreateButton() { return new MacButton; }
    MacBorder* CreateBorder() { return new MacBorder; }
};
 
class WinFactory: public AbstractFactory {
public:
    WinButton* CreateButton() { return new WinButton; }
    WinBorder* CreateBorder() { return new WinBorder; }
};