目录

基本概念

代码与实例

基本概念

抽象工厂模式（Abstract Factory），提供一个创建一系列相关或相互依赖对象的接口，从而无需指定他们具体的类。

抽象工厂的好处：

1. 易于交换产品系列，在一个应用中只需要在初始化的时候出现一次，这就使得改变一个应用的具体工厂变得非常容易，它只需要改变具体工厂即可使用不同的产品配置；

2. 让具体创建实例过程与客户端分离，客户端是通过它们的抽象接口操纵实例，产品的具体类名也被具体工厂分离，不会在客户端代码中出现

对应的UML图如下（此图来源于大话设计模式）

代码与实例

程序运行截图如下：

源码如下：

Head.h

#ifndef HEAD_H#define HEAD_H#include <iostream>#include <string>using namespace std;typedef string Department;typedef string User;//IUser接口，用于客户端访问，解除与具体数据库访问耦合class IUser{public:virtual void insert(User *user) {}virtual User getUser(int id){ return ""; }virtual ~IUser(){}};//SqlserverUser类，用于访问SQL Server的Userclass SqlserverUser : public IUser{public:void insert(User *user);User getUser(int id);~SqlserverUser();};//AccessUser类，用于访问Access的Userclass AccssUser : public IUser{public:void insert(User *user);User getUser(int id);~AccssUser();};//IDepartment接口，用于客户端访问，解除与具体数据库访问的耦合class IDepartment{public:virtual void insert(Department *department){}virtual Department *getDepartment(int id){ return nullptr; }virtual ~IDepartment(){}};//SqlServerDepartment类，用于访问SQL Server的Departmentclass SqlServerDepartment : public IDepartment{public:void insert(Department *department);Department *getDepartment(int id);~SqlServerDepartment();};//AccessDepartment类，用于访问Access的Deparmentclass AccessDepartment : public IDepartment{public:void insert(Department *department);Department *getDepartment(int id);~AccessDepartment();};//IFactory接口，定义一个创建访问Department表对象的抽象的工厂接口class IFactory{public:virtual IUser *createUser() { return nullptr; }virtual IDepartment *createDepartment(){ return nullptr; }virtual ~IFactory(){}};//SqlserverFactory类，实现IFactory接口，实例化SqlserverUser和SqlserverDepartmentclass SqlserverFactory : public IFactory{public:IUser *createUser();IDepartment *createDepartment();~SqlserverFactory();};//AccessFactory类，实现IFactory接口，实例化AccessUser和AccessDepartmentclass AccessFactory : public IFactory{public:IUser *createUser();IDepartment *createDepartment();~AccessFactory();};#endif//HEAD_H

Head.cpp

#include "Head.h"void SqlServerDepartment::insert(Department *department){cout << "在 SQL Server 中给 Department 表增加一条记录！" << endl;}Department *SqlServerDepartment::getDepartment(int id){cout << "在 SQL Server 中根据 ID 得到 Department 表中的一条记录！" << endl;return nullptr;}SqlServerDepartment::~SqlServerDepartment(){cout << "SqlServerDepartment desconstruction ! " << endl;}void AccessDepartment::insert(Department *department){cout << "在 Access 中给 Department 表增加一条记录！" << endl;}Department *AccessDepartment::getDepartment(int id){cout << "在 Access 中根据 ID 得到 Department 表中的一条记录！" << endl;return nullptr;}AccessDepartment::~AccessDepartment(){cout << "AccessDepartment desconstruction ! " << endl;}void SqlserverUser::insert(User *user){cout << "在 SQL Server 中给 User 表增加一条记录！" << endl;}User SqlserverUser::getUser(int id){cout << "在 SQL Server 中根据ID得到 User 表一条记录！" << endl;return "";}SqlserverUser::~SqlserverUser(){cout << "SqlserverUser desconstruction ! " << endl;}void AccssUser::insert(User *user){cout << "在 Access 中给 User 表增加一条记录！" << endl;}User AccssUser::getUser(int id){cout << "在 Access 中根据ID得到 User 表一条记录！" << endl;return "";}AccssUser::~AccssUser(){cout << "AccssUser desconstruction ! " << endl;}IUser * SqlserverFactory::createUser(){return new SqlserverUser;}IDepartment * SqlserverFactory::createDepartment(){return new SqlServerDepartment;}SqlserverFactory::~SqlserverFactory(){cout << "SqlserverFactory desconstruction ! " << endl;}IUser * AccessFactory::createUser(){return new AccssUser;}IDepartment * AccessFactory::createDepartment(){return new AccessDepartment;}AccessFactory::~AccessFactory(){cout << "AccessFactory desconstruction ! " << endl;}

main.cpp

#include "Head.h"int main(int *argc, int *argv){User *user = new User();Department *department = new Department();IFactory *factory = new SqlserverFactory();//IFactory *factory = new AccessFactory();IUser *iuser = factory->createUser();iuser->insert(user);iuser->getUser(1);IDepartment *iDepartment = factory->createDepartment();iDepartment->insert(department);iDepartment->getDepartment(1);cout << "\n 开始析构了！" << endl;delete iDepartment;delete iuser;delete factory;delete user;delete department;cout << "\n------------ 华 丽 的 结 束 分 割 线 ------------" << endl;getchar();return 0;}