1.UML

2.代码

#include <iostream>
using namespace std;class Subject{
public:virtual void Request() = 0;
};class RealSubject:public Subject
{
public:virtual void Request(){cout << "RealSubject" << endl;}
};
class Proxy:public Subject
{
public:RealSubject *real = nullptr;virtual void Request(){if(real == nullptr){real = new RealSubject();}real->Request();}
};class Client{
public:void dothing(Subject *object){object->Request();}
};int main()
{Client *c = new Client();Proxy *p = new Proxy();c->dothing(p);cout << "--endl--" << endl;return 0;
}

运行结果：

RealSubject
--endl--

练习：追求者

UML图

#include <iostream>
using namespace std;class Songliwu{
public:virtual void song_wawa() = 0;virtual void song_huahua() = 0;virtual void song_qiaokeli() = 0;
};
class MM{
public:string name;MM(string _name):name(_name){}
};class Persuit:public Songliwu
{
public:MM *mm;Persuit(MM *_mm):mm(_mm){}void song_wawa(){cout << mm->name <<":送娃娃" << endl;}void song_huahua(){cout << mm->name <<":送花花" << endl;}void song_qiaokeli(){cout << mm->name <<":送巧克力" << endl;}
};
class Proxy:public Songliwu
{
public:Persuit *gg;Proxy(MM *mm){gg = new Persuit(mm);}void song_wawa(){gg->song_wawa();}void song_huahua(){(*gg).song_huahua();}void song_qiaokeli(){(*gg).song_qiaokeli();}
};int main(void)
{MM *mm = new MM("韩梅梅");Proxy p(mm);p.song_wawa();p.song_huahua();p.song_qiaokeli();cout << "--endl--" << endl;return 0;
}

运行结果：

韩梅梅:送娃娃
韩梅梅:送花花
韩梅梅:送巧克力
--endl--

参考：https://lkmao.blog.csdn.net/article/details/128950278?ydreferer=aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3l1ZW5pX3poYW8vY2F0ZWdvcnlfMTIxNDI1MDUuaHRtbA%3D%3D