设计模式之工厂模式factory 抽象工厂模式 abstract factory

工厂模式 factory pattern提供创建对象的接口.

抽象工厂模式 abstract factory pattern

分析：

FactoryPattern.h

#ifndef _FACTORYPATTERN_H_#define _FACTORYPATTERN_H_typedef enum{SALE_OBJECT_CHILD,     //儿童手机SALE_OBJECT_YOUNESTER, //青年人手机SALE_OBJECT_OLD        //老年人手机}Saleobject;typedef enum{PHONE_TYPE_FEATURE,PHONE_TYPE_ANDROID,PHONE_TYPE_WINDOWSPHONE}PhoneType;typedef enum{TABLEPC_TYPE_ANDROID,TABLEPC_TYPE_WINDOWSPHONE,TABLEPC_TYPE_IPAD,TABLEPC_TYPE_BADA}TablePCType;#define NAME_MAX_LEN(256)#define MIN(a, b)       ((a<=b)?(a):(b))//手机类，为纯虚类class Phone{public:Phone();virtual ~Phone();//虚析构函数//使用主板，显示屏，外壳，键盘等物料来研发手机virtual bool developPhone(void) = 0;protected:int m_nMainboard;  //主板int m_nLcd;        //显示屏int m_nShell;      //外壳int m_nKeyboard;   //键盘};/* *手机有很多（派生出）很多手机，如功能手机，Android手机，WindowsPhone手机等。 *///功能手机class FeaturePhone:public Phone{public:FeaturePhone();~FeaturePhone();//virual关键字写不写都一样，这里都是虚函数//必须overidevirtual bool developPhone(void);protected:Saleobject m_eSaleobj; //手机销售面向人群};//Android手机class AndroidPhone:public Phone{public:AndroidPhone();~AndroidPhone();//virual关键字写不写都一样，这里都是虚函数//必须overidevirtual bool developPhone(void);private:char m_szOSName[NAME_MAX_LEN]; //操作系统名称，增加一个成员};//WindowsPhone手机class WPPhone:public Phone{public:WPPhone();~WPPhone();//virual关键字写不写都一样，这里都是虚函数//必须overidevirtual bool developPhone(void);private:char m_szOSName[NAME_MAX_LEN]; //增加一个成员};/* *设计一个手机生产工厂类 */class MobilePhoneFactory{public:MobilePhoneFactory();~MobilePhoneFactory();//根据要求生产手机的类型来生产手机const Phone * makePhone(PhoneType ephonetype);//注意生产的手机未做自动销毁处理（对象删除），自动销毁也不符合自然规律};#endif

分析：客户想要一部手机（儿童手机，青年人手机，老年人手机），而手机需要通过工厂生产。
在程序中表现为：要通过工厂类MobilePhoneFactory去实例化具体手机类FeaturePhone、AndroidPhone或WPPhone等。可以通过
MobilePhoneFactory *pcFactory = NULL;
pcFactory = new MobilePhoneFactory();


通过MobilePhoneFactory::makePhone即可得到想要的手机实例。
PhoneType ephonetype = PHONE_TYPE_ANDROID;
Phone *pcphone = NULL;
pcphone = (AndroidPhone *)pcFactory->makePhone(ephonetype);
pcFactory->makePhone(ephonetype);
if (NULL != pcphone)
{
   delete pcphone;
}
这样对客户来说,在整个过程中就不涉及到MobilePhoneFactory的具体子类,达到封装效果,也就减少错误修改的机会。


使用工厂方法 要注意几个角色，首先你要定义产品接口类，如上面的Phone，产品接口下有Phone接口的实现类,如FeaturePhone、AndroidPhone或WPPhone等,其次要有一个MobilePhoneFactory类，用来生成产品Phone。 

AbstractFactoryPattern.h

#ifndef _ABSTRCTORYFACTORYPATTERN_H_#define _ABSTRCTORYFACTORYPATTERN_H_#include "FactoryPattern.h"typedef enum{BRAND_NAME_SUMSANG,BRAND_NAME_HTC,BRAND_NAME_MAX}BrandId;//平板电脑classclass TablePC{public:TablePC();virtual ~TablePC();virtual void develpTablePC(void) = 0;protected:int m_nSize;int m_nColor;};//安卓平板电脑classclass AndroidTablePC:public TablePC{public://对比起见，这里不写virtual，效果是一样的。/*virtual*/ void develpTablePC(void);};//WindowsPhone平板电脑classclass WPTablePC:public TablePC{public:/*virtual*/ void develpTablePC(void);};//iPad平板电脑classclass iPadTablePC:public TablePC{public:/*virtual*/ void develpTablePC(void);};//Bada平板电脑classclass BadaTablePC:public TablePC{public:/*virtual*/ void develpTablePC(void);};/* *设计一个平板电脑生产工厂类 */class TablePCFactory{public:TablePCFactory();~TablePCFactory();//根据要求生产平板电脑的类型来生产平板电脑TablePC * makeTablePC(TablePCType etablepctype);};/* *即能生产手机也能生产平板电脑的工厂,抽象工厂类 */class Phone_TablePC_Factory{public:Phone_TablePC_Factory(const char *szName);~Phone_TablePC_Factory();//组装手机和平板电脑品牌，为便于实例化，引入一个品牌ID的参数，//实际应用中应用更复杂。virtual bool makeBrand(BrandId id)=0;protected:char m_szBrandName[NAME_MAX_LEN];              //品牌名MobilePhoneFactory *m_pcPhoneFactory;          //手机生产工厂TablePCFactory *m_pcPadFactory;                //平板电脑生产工厂};//能同时生产手机和平板电脑的代工工厂A,B（如富士康,MITAC）,为子类实现类//OEMAclass OEMAFactory:public Phone_TablePC_Factory{public:OEMAFactory();OEMAFactory(const char *szName);~OEMAFactory();virtual bool makeBrand(BrandId id);};//OEMBclass OEMBFactory:public Phone_TablePC_Factory{public:OEMBFactory();OEMBFactory(const char *szName);~OEMBFactory();virtual bool makeBrand(BrandId id);};#endif

FactoryPattern.cpp

// FactoryPattern.cpp : Defines the entry point for the console application.//#include "stdafx.h"#include "FactoryPattern.h"#include "AbstractFactoryPattern.h"#include <iostream>using namespace std;/* *工厂类实现 */Phone::Phone(){cout<<"Phone constructor"<<endl;}Phone::~Phone(){cout<<"Phone destructor"<<endl;}//////////////////////////////////////////////////////////////////////////FeaturePhone::FeaturePhone():Phone(){cout<<"FeaturePhone constructor"<<endl;}FeaturePhone::~FeaturePhone(){cout<<"FeaturePhone destructor"<<endl;}bool FeaturePhone::developPhone(){cout<<"develop FeaturePhone"<<endl;return true;}//////////////////////////////////////////////////////////////////////////AndroidPhone::AndroidPhone():Phone(){cout<<"AndroidPhone constructor"<<endl;}AndroidPhone::~AndroidPhone(){cout<<"AndroidPhone destructor"<<endl;}bool AndroidPhone::developPhone(){cout<<"develop AndroidPhone"<<endl;return true;}//////////////////////////////////////////////////////////////////////////WPPhone::WPPhone():Phone(){cout<<"WPPhone constructor"<<endl;}WPPhone::~WPPhone(){cout<<"WPPhone destructor"<<endl;}bool WPPhone::developPhone(){cout<<"develop WPPhone"<<endl;return true;}//////////////////////////////////////////////////////////////////////////MobilePhoneFactory::MobilePhoneFactory()/*:m_pcPhone(NULL)*/{cout<<"MobilePhoneFactory constructor"<<endl;}MobilePhoneFactory::~MobilePhoneFactory(){cout<<"MobilePhoneFactory destructor"<<endl;}const Phone * MobilePhoneFactory::makePhone(PhoneType ephonetype){Phone *pPhoneInstance = NULL;switch (ephonetype){case PHONE_TYPE_FEATURE:pPhoneInstance = new FeaturePhone();break;case PHONE_TYPE_ANDROID:pPhoneInstance = new AndroidPhone();break;case PHONE_TYPE_WINDOWSPHONE:pPhoneInstance = new WPPhone();break;default://ASSERT(false);break;}if (NULL != pPhoneInstance){pPhoneInstance->developPhone();}return pPhoneInstance;}/* *抽象工厂类实现 */TablePC::TablePC(){//}TablePC::~TablePC(){//}void AndroidTablePC::develpTablePC(void){cout<<"AndroidTablePC develpTablePC"<<endl;}void WPTablePC::develpTablePC(void){cout<<"WPTablePC develpTablePC"<<endl;}void iPadTablePC::develpTablePC(void){cout<<"iPadTablePC develpTablePC"<<endl;}void BadaTablePC::develpTablePC(void){cout<<"BadaTablePC develpTablePC"<<endl;}//平板电脑生产厂TablePCFactory::TablePCFactory()/*:m_pcTablePC(NULL)*/{cout<<"TablePCFactory constructor"<<endl;}TablePCFactory::~TablePCFactory(){cout<<"TablePCFactory destructor"<<endl;}TablePC *TablePCFactory::makeTablePC(TablePCType etablepctype){TablePC *ptablepc = NULL;switch(etablepctype){case TABLEPC_TYPE_ANDROID:break;case TABLEPC_TYPE_WINDOWSPHONE:break;case TABLEPC_TYPE_IPAD:break;case TABLEPC_TYPE_BADA:break;}if (NULL != ptablepc){ptablepc->develpTablePC();}return ptablepc;}Phone_TablePC_Factory::Phone_TablePC_Factory(const char *szName):m_pcPhoneFactory(NULL),m_pcPadFactory(NULL){cout<<"Phone_TablePC_Factory constructor"<<endl;memset(m_szBrandName, 0 , sizeof(char)*NAME_MAX_LEN);if(NULL != szName){strncpy(m_szBrandName, szName, MIN(NAME_MAX_LEN, strlen(szName)));}}Phone_TablePC_Factory::~Phone_TablePC_Factory(){if (NULL != m_pcPhoneFactory){delete m_pcPhoneFactory;m_pcPadFactory = NULL;}if (NULL != m_pcPadFactory){delete m_pcPadFactory;m_pcPadFactory = NULL;}cout<<"Phone_TablePC_Factory destructor"<<endl;}//SumSangOEMAFactory::OEMAFactory(const char *szName):Phone_TablePC_Factory(szName){cout<<"OEMAFactory overload constructor"<<endl;}OEMAFactory::OEMAFactory():Phone_TablePC_Factory(NULL){cout<<"OEMAFactory default constructor"<<endl;}OEMAFactory::~OEMAFactory(){cout<<"OEMAFactory destructor"<<endl;}bool OEMAFactory::makeBrand(BrandId id){bool bResult = true;cout<<"OEMAFactory makeBrand"<<endl;switch(id){case BRAND_NAME_SUMSANG:m_pcPhoneFactory = new MobilePhoneFactory();if (NULL != m_pcPhoneFactory){//生产WindowsPhone手机PhoneType ephonetype = PHONE_TYPE_WINDOWSPHONE;m_pcPhoneFactory->makePhone(ephonetype);}m_pcPadFactory = new TablePCFactory();if (NULL != m_pcPadFactory){//生产bada平板电脑TablePCType etabletype = TABLEPC_TYPE_BADA;m_pcPadFactory->makeTablePC(etabletype);}break;case BRAND_NAME_HTC:m_pcPhoneFactory = new MobilePhoneFactory();if (NULL != m_pcPhoneFactory){//生产Android手机PhoneType ephonetype = PHONE_TYPE_ANDROID;m_pcPhoneFactory->makePhone(ephonetype);}m_pcPadFactory = new TablePCFactory();if (NULL != m_pcPadFactory){//生产WindowsPhone平板电脑TablePCType etabletype = TABLEPC_TYPE_WINDOWSPHONE;m_pcPadFactory->makeTablePC(etabletype);}break;default:bResult = false;break;}return bResult;}//OEMBOEMBFactory::OEMBFactory(const char *szName):Phone_TablePC_Factory(szName){cout<<"OEMBFactory overload constructor"<<endl;}OEMBFactory::OEMBFactory():Phone_TablePC_Factory(NULL){cout<<"OEMBFactory default constructor"<<endl;}OEMBFactory::~OEMBFactory(){cout<<"OEMBFactory destructor"<<endl;}bool OEMBFactory::makeBrand(BrandId id){bool bResult = true;cout<<"OEMBFactory makeBrand"<<endl;switch(id){case BRAND_NAME_SUMSANG:m_pcPhoneFactory = new MobilePhoneFactory();if (NULL != m_pcPhoneFactory){//生产WindowsPhone手机PhoneType ephonetype = PHONE_TYPE_WINDOWSPHONE;m_pcPhoneFactory->makePhone(ephonetype);}m_pcPadFactory = new TablePCFactory();if (NULL != m_pcPadFactory){//生产bada平板电脑TablePCType etabletype = TABLEPC_TYPE_BADA;m_pcPadFactory->makeTablePC(etabletype);}break;case BRAND_NAME_HTC:m_pcPhoneFactory = new MobilePhoneFactory();if (NULL != m_pcPhoneFactory){//生产Android手机PhoneType ephonetype = PHONE_TYPE_ANDROID;m_pcPhoneFactory->makePhone(ephonetype);}m_pcPadFactory = new TablePCFactory();if (NULL != m_pcPadFactory){//生产WindowsPhone平板电脑TablePCType etabletype = TABLEPC_TYPE_WINDOWSPHONE;m_pcPadFactory->makeTablePC(etabletype);}break;default:bResult = false;break;}return true;}int main(int argc, char* argv[]){MobilePhoneFactory *pcFactory = NULL;pcFactory = new MobilePhoneFactory();if (NULL != pcFactory){//当客户需要生产安卓手机时，通过MobilePhoneFactory::makePhone即可得到。PhoneType ephonetype = PHONE_TYPE_ANDROID;Phone *pcphone = NULL;pcphone = (AndroidPhone *)pcFactory->makePhone(ephonetype);pcFactory->makePhone(ephonetype);if (NULL != pcphone){delete pcphone;}//如果客户需要生产iPhone手机，先从Phone派生一个iPhone类，然后在MobilePhoneFactory//中new出iPhone类即可。delete pcFactory;}cout<<"------------------------------------------"<<endl;// 通过OEMA生产HTC品牌Phone_TablePC_Factory *pcOEMFactory = NULL;pcOEMFactory = new OEMAFactory("HTC");pcOEMFactory->makeBrand(BRAND_NAME_HTC);delete pcOEMFactory;cout<<"------------------------------------------"<<endl;// 通过OEMB生产SUMSANG品牌pcOEMFactory = new OEMBFactory("SUMSANG");pcOEMFactory->makeBrand(BRAND_NAME_SUMSANG);delete pcOEMFactory;return 0;}