《C++新经典设计模式》之第8章 外观模式
外观模式.cpp
cpp
#include <iostream>
#include <memory>
using namespace std;
// 中间层角色，隔离接口，两部分模块通过中间层打交道
// 提供简单接口，不与底层直接打交道
// 提供统一接口，访问子系统中的一群接口
// 定义高层接口，让子系统更容易使用
// 迪米特法则
// 一个对象对其他对象的了解应尽可能少，降低对象间耦合，提高系统的可维护性
namespace ns1
{
class graphic // 图形相关类
{
graphic(){};
graphic(const graphic &tmpobj);
graphic &operator=(const graphic &tmpobj);
~graphic(){};
public:
static graphic &getInstance()
{
static graphic instance;
return instance;
}
public:
void display(bool enable) // 是否全屏显示(true：是)
{
cout << "full screen->" << enable << endl;
}
void effect(bool enable) // 是否开启特效(true：是)
{
cout << "special effects->" << enable << endl;
}
void resolution(int index) // 设置窗口分辨率
{
cout << "resolution ratio->" << index << endl;
}
void antialiasing(bool enable) // 是否开启抗锯齿(true：是)
{
cout << "anti-aliasing->" << enable << endl;
}
};
class sound // 声音相关类
{
sound(){};
sound(const sound &tmpobj);
sound &operator=(const sound &tmpobj);
~sound(){};
public:
static sound &getInstance()
{
static sound instance;
return instance;
}
public:
void bgsound(bool enable) // 是否开启背景声音(true：是)
{
cout << "background sound->" << enable << endl;
}
void envirsound(bool enable) // 是否开启环境音效(true：是)
{
cout << "environmental sound effect->" << enable << endl;
}
void expsound(bool enable) // 是否开启表情声音(true：是)
{
cout << "expressional voice->" << enable << endl;
}
void setvolume(int level) // 音量大小设置(0-100)
{
cout << "volume->" << level << endl;
}
};
class chatvoice // 语音聊天相关类
{
chatvoice(){};
chatvoice(const chatvoice &tmpobj);
chatvoice &operator=(const chatvoice &tmpobj);
~chatvoice(){};
public:
static chatvoice &getInstance()
{
static chatvoice instance;
return instance;
}
public:
void micvolume(int level) // 麦克风音量大小设置(0-100)
{
cout << "microphone volume->" << level << endl;
}
void micsens(int level) // 麦克灵敏度设置(0-100)
{
cout << "microphone sensitivity->" << level << endl;
}
void chatvolume(int level) // 聊天音量设置(0-100)
{
cout << "chat volume->" << level << endl;
}
};
class conffacade // 扮演外观模式角色的类
{
conffacade(){};
conffacade(const conffacade &tmpobj);
conffacade &operator=(const conffacade &tmpobj);
~conffacade(){};
public:
static conffacade &getInstance()
{
static conffacade instance;
return instance;
}
public:
void LowConfComputer() // 对于低配置电脑，只开启一些低配置选项
{
graphic &g_gp = graphic::getInstance();
g_gp.display(true); // 全屏耗费资源更低
g_gp.effect(false);
g_gp.resolution(2);
g_gp.antialiasing(false);
sound &g_snd = sound::getInstance();
g_snd.bgsound(false);
g_snd.envirsound(false);
g_snd.expsound(false);
g_snd.setvolume(15);
chatvoice &g_cv = chatvoice::getInstance();
g_cv.micvolume(20);
g_cv.micsens(50);
g_cv.chatvolume(60);
}
void HighConfComputer() // 对于高配置电脑，能达到最好效果的项全部开启
{
graphic &g_gp = graphic::getInstance();
g_gp.display(false);
g_gp.effect(true);
g_gp.resolution(0);
g_gp.antialiasing(true);
sound &g_snd = sound::getInstance();
g_snd.bgsound(true);
g_snd.envirsound(true);
g_snd.expsound(true);
g_snd.setvolume(50);
chatvoice &g_cv = chatvoice::getInstance();
g_cv.micvolume(100);
g_cv.micsens(100);
g_cv.chatvolume(100);
}
};
}
namespace ns2
{
class Screen // 屏幕
{
public:
void On() { cout << "screen on!" << endl; }
void Off() { cout << "screen off!" << endl; }
};
class Light // 灯光
{
public:
void On() { cout << "light open!" << endl; }
void Off() { cout << "light close!" << endl; }
};
class Speaker // 音箱
{
public:
void On() { cout << "speaker on!" << endl; }
void Off() { cout << "speaker off!" << endl; }
};
class DvdPlayer // DVD播放器
{
public:
void On() { cout << "dvd open!" << endl; }
void Off() { cout << "dvd close!" << endl; }
};
class PlayerStation // 游戏机
{
public:
void On() { cout << "playerstation on!" << endl; }
void Off() { cout << "playerstation off!" << endl; }
};
class HomeTheaterFacade // 家庭影院外观模式类
{
Screen scnobj;
Light lgobj;
Speaker spkobj;
DvdPlayer dpobj;
PlayerStation psobj;
public:
void WatchMovie() // 看电影
{
// 屏幕打开，灯光熄灭，音箱打开，DVD播放器打开，游戏机关闭。
scnobj.On();
lgobj.Off();
spkobj.On();
dpobj.On();
psobj.Off();
}
void PlayGame() // 玩游戏
{
// 屏幕打开，灯光打开，音箱打开，DVD播放器关闭，游戏机打开。
scnobj.On();
lgobj.On();
spkobj.On();
dpobj.Off();
psobj.On();
}
};
}
namespace ns3
{
class Shape
{
public:
virtual ~Shape() = default;
virtual void draw() const = 0;
};
class Rectangle : public Shape
{
public:
void draw() const override { cout << "Rectangle::draw()" << endl; }
};
class Square : public Shape
{
public:
void draw() const override { cout << "Square::draw()" << endl; }
};
class Circle : public Shape
{
public:
void draw() const override { cout << "Circle::draw()" << endl; }
};
class ShapeMaker
{
shared_ptr<Shape> circle;
shared_ptr<Shape> rectangle;
shared_ptr<Shape> square;
public:
ShapeMaker()
{
circle = make_shared<Circle>();
rectangle = make_shared<Rectangle>();
square = make_shared<Square>();
}
void drawCircle() const { circle->draw(); }
void drawRectangle() const { rectangle->draw(); }
void drawSquare() const { square->draw(); }
};
}
int main()
{
#if 0
using namespace ns1;
graphic &g_gp = graphic::getInstance();
g_gp.display(false);
g_gp.effect(true);
g_gp.resolution(2);
g_gp.antialiasing(false);
cout << "---------------" << endl;
sound &g_snd = sound::getInstance();
g_snd.setvolume(80);
g_snd.envirsound(true);
g_snd.bgsound(false);
cout << "---------------" << endl;
chatvoice &g_cv = chatvoice::getInstance();
g_cv.chatvolume(70);
g_cv.micsens(65);
#endif
#if 0
using namespace ns1;
conffacade &g_cffde = conffacade::getInstance();
cout << "Low-configuration computer" << endl;
g_cffde.LowConfComputer();
cout << "------------------" << endl;
cout << "high-configuration computer" << endl;
g_cffde.HighConfComputer();
#endif
#if 0
ns2::HomeTheaterFacade htfacobj;
cout << "movie---------------" << endl;
htfacobj.WatchMovie();
cout << "game---------------" << endl;
htfacobj.PlayGame();
#endif
#if 1
using namespace ns3;
shared_ptr<ShapeMaker> shapeMaker(new ShapeMaker());
shapeMaker->drawCircle();
shapeMaker->drawRectangle();
shapeMaker->drawSquare();
#endif
cout << "Over!\n";
return 0;
}