设计模式：7 代理模式

代理模式:为其他对象提供一种代理以控制对这个对象的访问

Subject类：定义了RealSubject和Proxy的共用接口，这样就在任何使用RealSubject的地方使用Proxy

 

代理模式应用:

1远程代理：为一个对象在不同的地址空间提供局部代表，隐藏一个对象存在于不同地址空间的事实

 

2虚拟代理：根据需要创建开销很大的对象，通过它来存放实例化需要很长时间的真实对象

 

3安全代理：控制真是对象访问时的权限

 

4智能指引：当调用真实的对象时，代理处理另外一些事实。[智能指针]

 

main.cpp

#include <iostream>#include <stdlib.h>#include "SchoolGirl.h"#include "Proxy.h"using namespace std;void process(){SchoolGirl panyin("潘颖");Proxy agent(panyin);agent.giveChocolate();agent.giveDolls();agent.giveFlower();}int main(int argc,char* argv[]){process();system("pause");return 0;}

 

SchoolGirl.h

#ifndef SCHOOLGIRL_H#define SCHOOLGIRL_H#include <string>class SchoolGirl{public:SchoolGirl(const std::string& sName);~SchoolGirl(void);std::string getName();public:std::string _sName;};#endif

SchoolGirl.cpp

#include "SchoolGirl.h"SchoolGirl::SchoolGirl(const std::string& sName):_sName(sName){}SchoolGirl::~SchoolGirl(void){}std::string SchoolGirl::getName(){return _sName;}

Proxy.h

#ifndef PROXY_H#define PROXY_H#include "givegift.h"#include "Pursuit.h"#include "SchoolGirl.h"#include <memory>class Proxy :public GiveGift{public:Proxy(SchoolGirl& mm);~Proxy(void);void giveFlower();void giveChocolate();void giveDolls();private:std::shared_ptr<Pursuit> _ptrPursuit;//关键：代理模式聚合了真正的主类去，在代理中的方法全部源自真正主类的方法};#endif

 

Proxy.cpp

#include "Proxy.h"Proxy::Proxy(SchoolGirl& mm){_ptrPursuit.reset(new Pursuit(mm));}Proxy::~Proxy(void){}void Proxy::giveFlower(){_ptrPursuit->giveFlower();}void Proxy::giveChocolate(){_ptrPursuit->giveChocolate();}void Proxy::giveDolls(){_ptrPursuit->giveDolls();}

GiveGift.h

#ifndef GIVEGIFT_H#define GIVEGIFT_H//主类class GiveGift{public:GiveGift(void);virtual ~GiveGift(void);virtual void giveFlower();virtual void giveChocolate();virtual void giveDolls();};#endif

GiveGift.cpp

#include "GiveGift.h"GiveGift::GiveGift(void){}GiveGift::~GiveGift(void){}void GiveGift::giveFlower(){}void GiveGift::giveChocolate(){}void GiveGift::giveDolls(){}