学步园

#include <iostream>
using namespace std;

class reciver //执行者
{
public:
    void action()
    {
        cout<< "reciver::action()"<<endl;
    }
};

class command //命令
{
public:
    command(reciver *rec):_rec(rec){}
    virtual ~command(){}

    virtual void execute() =0;
protected:
    reciver *_rec;
};

class concrete_command: public command
{
public:
    concrete_command(reciver *rec):command(rec){}
    void execute()
    {
        _rec->action();
    }
};

class invoker //派发命令者
{
public:
    invoker(command *com):_com(com){}
    void execute_command()
    {
        _com->execute();
    }

    void set_command(command *com)
    {
        _com = com;
    }
private:
    command *_com;
};

int main()
{
    reciver *r = new reciver;
    command *c = new concrete_command(r);
    invoker *i = new invoker(c);

    i->execute_command();
    delete i;delete c;delete r;
    return 0;
}

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

class barbecuer
{
public:
    void bake_mutton()
    {
        cout<< "bake mutton..."<<endl;
    }
    void bake_chicken_wing()
    {
        cout<< "bake chicken wing..."<<endl;
    }
};

class command
{
public:
    command(barbecuer *rec):_rec(rec){}
    virtual ~command(){}
    virtual void execute() =0;
protected:
    barbecuer *_rec;
};

class bake_mutton_command : public command
{
public:
    bake_mutton_command(barbecuer *rec):command(rec){}
    void execute()
    {
        _rec->bake_mutton();
    }
};

class bake_chicken_wing_command : public command
{
public:
    bake_chicken_wing_command(barbecuer *rec):command(rec){}
    void execute()
    {
        _rec->bake_chicken_wing();
    }
};

class waiter
{
public:
    void add_order(command *com)
    {
        coms.push_back(com);
    }
    void cancel_order(command *com)
    {
    }
    void notify()
    {
        for (vector<command*>::iterator it = coms.begin();
            it != coms.end(); ++it)
            (*it)->execute();
    }

private:
    vector<command *> coms;
};

int main()
{
    barbecuer *boy = new barbecuer();
    command *bakeMutton1 = new bake_mutton_command(boy);
    command *bakeMutton2 = new bake_mutton_command(boy);
    command *bakeChickenWing = new bake_chicken_wing_command(boy);
    waiter girl;
    girl.add_order(bakeMutton1);
    girl.add_order(bakeMutton2);
    girl.add_order(bakeChickenWing);
    girl.notify();
    delete boy;
    delete bakeChickenWing;
    delete bakeMutton1;
    delete bakeMutton2;
    return 0;
}