设计模式之代理模式（Proxy Pattern）

　　定义：为其他对象提供一种代理以控制这个对象的访问，也叫做委托模式。

　　咱们比作游戏，通俗讲代理模式就是，一个主题虚基类派生出两个子类，一个玩家类，实现相关操作，一个是代练类，代替执行玩家相关操作，代练类对象有个指向玩家类对象的指针，可以通过调用代练类对象，实现玩家不登录，游戏照样打怪升级。。。。　　

using namespace std;
//游戏主题类
class Game
{
public:
    Game() {}
    virtual ~Game() {}
    virtual void begin_time() = 0;
    virtual void login() = 0;
    virtual void killBoss() = 0;
    virtual void upGrade() = 0;
    virtual void end_time() = 0;
};

//游戏实例
class RealGame : public Game
{
public:
    RealGame(string username, string password) 
    {
        this->userName = username;
        this->password = password;
    }
    ~RealGame() {}
    //上线
    virtual void begin_time() 
    { 
        printf("开始时间： 2017/3/20 19:34\n"); 
    }
    //登录
    virtual void login() 
    { 
        cout <<"用户: " <<userName<<"登录游戏"<< endl;
    }
    //打怪
    virtual void killBoss() 
    { 
        cout << userName << "打死领主\"锤王菠萝丁！\"" << endl;
    }
    //升级
    virtual void upGrade() 
    { 
        cout << userName << "升级到89级！" << endl;
    }
    //下线
    virtual void end_time() 
    {
        cout <<"2017/3/20 21:12 玩家"<< userName << "退出游戏" << endl;
    }

private:
    string userName;
    string password;
};

//游戏代练者
class Proxy : public Game
{
public:
    Proxy(string userName, string password)
    {
        pRealGame = new RealGame(userName, password);
    }
    ~Proxy() 
    {
        delete pRealGame;
        pRealGame = nullptr;
    }

    virtual void begin_time() 
    {
        pRealGame->begin_time();
    }
    virtual void login()
    {
        pRealGame->login();
    }
    virtual void killBoss()
    {
        pRealGame->killBoss();
    }
    virtual void upGrade()
    {
        pRealGame->upGrade();
    }
    virtual void end_time()
    {
        pRealGame->end_time();
    }

private:
    RealGame *pRealGame;
};

int main()
{
    Game *m_game = new Proxy("张三","******");
    m_game->begin_time();
    m_game->login();
    m_game->killBoss();
    m_game->upGrade();
    m_game->end_time();

    delete m_game;
    m_game = nullptr;
}