设计模式之命令模式（Command）

     命令模式（Command）把请求封装成一个对象，使请求能够存储更多的信息拥有更多的能力。命令模式同样能够把请求的发送者和接收者解耦，但它不关心请求将以何种方式被处理。命令模式经常与职责链模式（Chain of Responsibility）和组合模式（Composite）一起使用：职责链模式处理命令模式封装的对象，组合模式可以把简单的命令对象组合成复杂的命令对象。

      本文举了一个在饭店点菜的例子。（1）烤肉师傅负责在后台（厨房）做饭。（2）Command负责提供提供各种命令，相当于菜单。（3）服务员与客服打交道，负责记录客户点了哪些菜（把客户的命令记下来），然后交给厨师去做。（4）客户就负责点菜。

代码：

#include <iostream>   
#include <vector>   
#include <string>   
using namespace std;  
  
  
class Command;  
class MakeChikenCmd;  
class MakeMuttonCmd;  
//烤肉师傅   
class RoastCook{   
    friend class MakeChikenCmd;  
    friend class MakeMuttonCmd;  
private:  
    void MakeMutton()   
    { cout << "烤羊肉"; }  
    void MakeChickenWing()   
    { cout << "烤鸡翅膀"; }  
};  
  
//命令的接口，抽象类   
class Command{  
public:  
    Command(RoastCook* cook)  
    {  
        cooker = cook;  
    }  
    virtual ~Command(){}  
    virtual void Execute()=0;  
protected:  
    RoastCook *cooker;//包含了烤肉师傅的对象   
};  
  
//烤羊肉命令   
class MakeMuttonCmd : public Command{  
public:  
    MakeMuttonCmd(RoastCook *cook):Command(cook){}  
    void Execute()  
    {  
        cooker->MakeMutton();  
    }  
};  
//烤鸡肉命令   
class MakeChikenCmd : public Command{  
public:  
    MakeChikenCmd(RoastCook *cook):Command(cook){}  
    void Execute()  
    {  
        cooker->MakeChickenWing();  
    }  
};  
  
//服务员类，负责与客服交互   
class Waiter{  
public:  
    Waiter(string _name)  
    {this->name = _name;}  
    void AddOder(Command* subOder)//加入客户点的菜   
    {  
        oder.push_back(subOder);  
    }  
  
    void Notify()  
    {  
        vector<Command*>::iterator iter;  
        cout<<name<<" 通知烤肉师傅请做:"<<endl;  
        for(iter = oder.begin();iter!=oder.end();++iter){  
            cout<<"                   ";  
            (*iter)->Execute();  
            cout<<endl;  
        }  
    }  
  
    string getName()const  
    {return name;}  
private:  
    vector<Command*> oder;//点菜单   
    string name;//服务员名字   
};  
  
class Custmer{  
public:  
    Custmer(string myname)  
    {  
        this->name = myname;  
        this->w = NULL;  
    }  
  
    void CustmerOder(Command *cmd)  
    {  
        cout<<"顾客"<<name<<"点菜"<<endl;  
        w->AddOder(cmd);  
    }  
  
    void CallWaiter(Waiter *_w)  
    {  
        cout<<"顾客"<<name<<"呼叫服务员"<<endl;  
        this->w = _w;  
        cout<<"服务员"<<w->getName()<<"为您服务"<<endl;  
    }  
private:  
    string name;  
    Waiter *w;  
};  
  
int main()  
{  
    RoastCook *cooker = new RoastCook();  
    Command *cmd = new MakeChikenCmd(cooker);  
    Command *cmd1 = new MakeMuttonCmd(cooker);  
  
    Waiter waiter("sps");  
    Custmer cust("lsj");  
    cust.CallWaiter(&waiter);//呼叫服务员   
  
    cust.CustmerOder(cmd);//点菜   
    cust.CustmerOder(cmd1);//点菜   
  
    waiter.Notify();//服务员通知后台   
  
    system("pause");  
    return 0;  
}  

#include <iostream>
#include <vector>
#include <string>
using namespace std;


class Command;
class MakeChikenCmd;
class MakeMuttonCmd;
//烤肉师傅
class RoastCook{ 
	friend class MakeChikenCmd;
	friend class MakeMuttonCmd;
private:
	void MakeMutton() 
	{ cout << "烤羊肉"; }
	void MakeChickenWing() 
	{ cout << "烤鸡翅膀"; }
};

//命令的接口，抽象类
class Command{
public:
	Command(RoastCook* cook)
	{
		cooker = cook;
	}
    virtual ~Command(){}
	virtual void Execute()=0;
protected:
	RoastCook *cooker;//包含了烤肉师傅的对象
};

//烤羊肉命令
class MakeMuttonCmd : public Command{
public:
	MakeMuttonCmd(RoastCook *cook):Command(cook){}
	void Execute()
	{
		cooker->MakeMutton();
	}
};
//烤鸡肉命令
class MakeChikenCmd : public Command{
public:
	MakeChikenCmd(RoastCook *cook):Command(cook){}
	void Execute()
	{
		cooker->MakeChickenWing();
	}
};

//服务员类，负责与客服交互
class Waiter{
public:
	Waiter(string _name)
	{this->name = _name;}
	void AddOder(Command* subOder)//加入客户点的菜
	{
		oder.push_back(subOder);
	}

	void Notify()
	{
		vector<Command*>::iterator iter;
		cout<<name<<" 通知烤肉师傅请做:"<<endl;
		for(iter = oder.begin();iter!=oder.end();++iter){
			cout<<"                   ";
			(*iter)->Execute();
			cout<<endl;
		}
	}

	string getName()const
	{return name;}
private:
	vector<Command*> oder;//点菜单
	string name;//服务员名字
};

class Custmer{
public:
	Custmer(string myname)
	{
		this->name = myname;
		this->w = NULL;
	}

	void CustmerOder(Command *cmd)
	{
		cout<<"顾客"<<name<<"点菜"<<endl;
		w->AddOder(cmd);
	}

	void CallWaiter(Waiter *_w)
	{
	    cout<<"顾客"<<name<<"呼叫服务员"<<endl;
		this->w = _w;
		cout<<"服务员"<<w->getName()<<"为您服务"<<endl;
	}
private:
	string name;
	Waiter *w;
};

int main()
{
	RoastCook *cooker = new RoastCook();
	Command *cmd = new MakeChikenCmd(cooker);
	Command *cmd1 = new MakeMuttonCmd(cooker);

    Waiter waiter("sps");
	Custmer cust("lsj");
    cust.CallWaiter(&waiter);//呼叫服务员

	cust.CustmerOder(cmd);//点菜
	cust.CustmerOder(cmd1);//点菜

	waiter.Notify();//服务员通知后台

	system("pause");
	return 0;
}

补充：软件开发 , C++ ,

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