设计模式学习--抽象工厂模式

抽象工厂模式是对象创建形模式的一种。抽象工厂模式是指当有多个抽象角色时，使用的一种工厂模式。抽象工厂模式可以向客户端提供一个接口，使客户端在不必指定产品的具体的情况下，创建多个产品族中的产品对象。总的来说就是当发现需要创建一系列的对象，而此时发现耦合又高，为了以后的可扩展性，可以使用该模式。该模式的UML图如下：

意图：提供一个创建一系列相关或相互依赖对象的接口，而无需指定他们的具体类
适用性：1 一个系统要独立于它的产品的创建，组合和表示时；
2 一个系统要由多个产品系列中的一个配置时；
3 当你提供一个产品类时，而只是想表示他们的接口而不是实现时；
协作 ：通常在运行的时刻创建一个ConcreateFactory的实列，为创建不同的产品，客户应使用不同的具体工厂。AbstractoryFactory把创建产品对象的任务推迟到他的子类
优缺点 优点
1 分离了具体的类，客户与类的实现分离，产品的类名也不出现的客户的代码当中
2 易与交换产品系列
3 有利于产品的一致性
缺点
1 难于支持新的 产品 ，因为抽象工厂类的接口已经写好了，要实现另外的产品必须要修改抽象工厂的类的接
口和增加新的产品类
下面是以假设生产人种为例，三种肤色的人种，性别有男女 例子：
首先是UML图：

下面是实现，首先是人种的接口类Human

#pragma once//人类接口class Human{public:    //相应的人种颜色    virtual void getColor();    //说话    virtual void talk();    //性别    virtual void getSex();private:};#include "Human.h"void Human::getColor(){}void Human::talk(){}void Human::getSex(){}//具体的黑色人种//AbstractBlackHuman.h#pragma once#include "Human.h"#include <iostream>class AbstractBlackHuman : public Human{public:    AbstractBlackHuman();    ~AbstractBlackHuman();    void getColor();    void talk();private:};#include "AbstractBlackHuman.h"using namespace std;AbstractBlackHuman::AbstractBlackHuman(){}AbstractBlackHuman::~AbstractBlackHuman(){}void AbstractBlackHuman::getColor(){    cout << "黑色人种的皮肤颜色是黑色的" <<endl;}void AbstractBlackHuman::talk(){    cout << "黑色人种一般说的是多字节" << endl;}//黑色女性#pragma once#include "AbstractBlackHuman.h"#include <iostream>class FemaleBlackHuman : public AbstractBlackHuman{public:    FemaleBlackHuman();    ~FemaleBlackHuman();    void getSex();private:};#include "FemaleBlackHuman.h"using namespace std;FemaleBlackHuman::FemaleBlackHuman(){}FemaleBlackHuman::~FemaleBlackHuman(){}void FemaleBlackHuman::getSex(){    cout << "黑色女性" << endl;}//黑色男性#pragma once#include "AbstractBlackHuman.h"#include <iostream>class MaleBlackHuman : public AbstractBlackHuman{public:    MaleBlackHuman();    ~MaleBlackHuman();    void getSex();private:};#include "MaleBlackHuman.h"using namespace std;MaleBlackHuman::MaleBlackHuman(){}MaleBlackHuman::~MaleBlackHuman(){}void MaleBlackHuman::getSex(){    cout << "黑色男性" << endl;}//白色人种//AbstractWhiteHuman.h#pragma once#include "Human.h"#include <iostream>class AbstractWhiteHuman : public Human{public:    AbstractWhiteHuman();    ~AbstractWhiteHuman();    void getColor();    void talk();private:};#include "AbstractWhiteHuman.h"using namespace std;AbstractWhiteHuman::AbstractWhiteHuman(){}AbstractWhiteHuman::~AbstractWhiteHuman(){}void AbstractWhiteHuman::getColor(){    cout << "白色人种的皮肤颜色是白色的" << endl;}void AbstractWhiteHuman::talk(){    cout << "白色人种一般说的是单字节" << endl;}//白色女性#pragma once#include "AbstractWhiteHuman.h"#include <iostream>class FemaleWhiteHuman : public AbstractWhiteHuman{public:    FemaleWhiteHuman();    ~FemaleWhiteHuman();    void getSex();private:};#include "FemaleWhiteHuman.h"using namespace std;FemaleWhiteHuman::FemaleWhiteHuman(){}FemaleWhiteHuman::~FemaleWhiteHuman(){}void FemaleWhiteHuman::getSex(){    cout << "白色女性" << endl;}//白色男性#pragma once#include "AbstractWhiteHuman.h"#include <iostream>class MaleWhiteHuman : public AbstractWhiteHuman{public:    MaleWhiteHuman();    ~MaleWhiteHuman();    void getSex();private:};#include "MaleWhiteHuman.h"using namespace std;MaleWhiteHuman::MaleWhiteHuman(){}MaleWhiteHuman::~MaleWhiteHuman(){}void MaleWhiteHuman::getSex(){    cout << "白色男性" << endl;}//黄色人种//AbstractYellowHuman.h#pragma once#include "Human.h"#include <iostream>class AbstractYellowHuman : public Human{public:    AbstractYellowHuman();    ~AbstractYellowHuman();    void getColor();    void talk();private:};#include "AbstractYellowHuman.h"using namespace std;AbstractYellowHuman::AbstractYellowHuman(){}AbstractYellowHuman::~AbstractYellowHuman(){}void AbstractYellowHuman::getColor(){    cout << "黄色人种的皮肤颜色是黄色的" << endl;}void AbstractYellowHuman::talk(){    cout << "黄色人种一般说的是双字节" << endl;}//黄色女性#pragma once#include "AbstractYellowHuman.h"#include <iostream>class FemaleYellowHuman : public AbstractYellowHuman{public:    FemaleYellowHuman();    ~FemaleYellowHuman();    void getSex();private:};#include "FemaleYellowHuman.h"using namespace std;FemaleYellowHuman::FemaleYellowHuman(){}FemaleYellowHuman::~FemaleYellowHuman(){}void FemaleYellowHuman::getSex(){    cout << "黄色女性" << endl;}//黄色男性#pragma once#include "AbstractYellowHuman.h"#include <iostream>class MaleYellowHuman : public AbstractYellowHuman{public:    MaleYellowHuman();    ~MaleYellowHuman();    void getSex();private:};#include "MaleYellowHuman.h"using namespace std;MaleYellowHuman::MaleYellowHuman(){}MaleYellowHuman::~MaleYellowHuman(){}void MaleYellowHuman::getSex(){    cout << "黄色男性" << endl;}

以上是产品的信息类，都是继承与Human类，Human作为人类的抽象接口。接下来就是工厂类，工厂类也有一个抽象的接口HumanFactory，采用纯虚函数：

#pragma once#include "Human.h"class HumanFactory{public:    HumanFactory();    ~HumanFactory();    virtual Human* createBlackHuman() = 0;    virtual Human* createWhiteHuman() = 0;    virtual Human* createYellowHuman() = 0;private:};//男性工厂类，返回三种人种的男性#pragma once#include "HumanFactory.h"#include "MaleBlackHuman.h"#include "MaleWhiteHuman.h"#include "MaleYellowHuman.h"class MaleFactory : public HumanFactory{public:    MaleFactory();    ~MaleFactory();    Human* createBlackHuman();    Human* createWhiteHuman();    Human* createYellowHuman();private:};#include "MaleFactory.h"MaleFactory::MaleFactory(){}MaleFactory::~MaleFactory(){}Human* MaleFactory::createBlackHuman(){    return new MaleBlackHuman();}Human* MaleFactory::createWhiteHuman(){    return new MaleWhiteHuman();}Human* MaleFactory::createYellowHuman(){    return new MaleYellowHuman();}//女性产品的工厂类，返回三种人种的女性类#pragma once#include "HumanFactory.h"#include "FemaleBlackHuman.h"#include "FemaleWhiteHuman.h"#include "FemaleYellowHuman.h"class FemaleFactory : public HumanFactory{public:    FemaleFactory();    ~FemaleFactory();    Human* createBlackHuman();    Human* createWhiteHuman();    Human* createYellowHuman();private:};#include "FemaleFactory.h"FemaleFactory::FemaleFactory(){}FemaleFactory::~FemaleFactory(){}Human* FemaleFactory::createBlackHuman(){    return new FemaleBlackHuman();}Human* FemaleFactory::createWhiteHuman(){    return new FemaleWhiteHuman();}Human* FemaleFactory::createYellowHuman(){    return new FemaleYellowHuman();}

产品类和工厂类的实现完成了，接下来就客户调用的方法了，

#include "stdafx.h"#include "Human.h"#include "HumanFactory.h"#include "FemaleFactory.h"#include "MaleFactory.h"#include <iostream>using namespace std;int _tmain(int argc, _TCHAR* argv[]){   //生产女性工厂    HumanFactory* femaleFactory = new FemaleFactory();    //女性工厂生产出的黑色皮肤的女性    Human* femaleBlackHuam = femaleFactory->createBlackHuman();    femaleBlackHuam->getColor();    femaleBlackHuam->getSex();    femaleBlackHuam->talk();    //男性工厂    HumanFactory* maleFactory = new MaleFactory();    //男性工厂生产出的黑色皮肤的男性    Human* maleBlackHuame = maleFactory->createBlackHuman();    maleBlackHuame->getColor();    maleBlackHuame->getSex();    maleBlackHuame->talk();    return 0;}

抽象工厂的学习先告一段落，以后有更好的理解的时候，回来修改。