C++设计模式浅识中介者模式

[code]//前向声明
class Abstract;

//中介者抽象类
class Mediator{
public:
    virtual void Send(std::string message, Abstract *abstract){}
};

//抽象类
class Abstract{
protected:
    Mediator *mediator;
public:
    //构造中介者
    Abstract(Mediator *mediator){
        this->mediator = mediator;
    }
};

//具体抽象类1
class ConcreteAbstract1: public Abstract{
public:
    ConcreteAbstract1(Mediator *me):Abstract(me){}
    void Send(std::string message){
        //中介者送出去
        mediator->Send(message, this);
    }
    void Notify(std::string message){
        std::cout << "ConcreteAbstract1 receive message: " << message << "   ---(From ConcreteAbstract2)" << std::endl;
    }
};

//具体抽象类2
class ConcreteAbstract2: public Abstract{
public:
    ConcreteAbstract2(Mediator *me):Abstract(me){}
    void Send(std::string message){
        //中介者送出去
        mediator->Send(message, this);
    }
    void Notify(std::string message){
        std::cout << "ConcreteAbstract2 receive message: "  << message << "   ---(From ConcreteAbstract1)" << std::endl;
    }
};

//具体中介者
class ConcreteMediator: public Mediator{
private:
    //需了解所存的具体抽象类对象
    ConcreteAbstract1 *CA1;
    ConcreteAbstract2 *CA2;
public:
    ConcreteMediator(){}
    void setConcreteMediator(ConcreteAbstract1 *CA1, ConcreteAbstract2 *CA2){
        this->CA1 = CA1;
        this->CA2 = CA2;
    }
    virtual void Send(std::string message, Abstract *abstract){
        if(abstract == CA1)
            CA2->Notify(message);
        else
            CA1->Notify(message);
    }
};

[code]//Client
int main(){
    ConcreteMediator *m = new ConcreteMediator;

    //具体的抽象这认识具体的中介者
    ConcreteAbstract1 *ca1 = new ConcreteAbstract1(m);
    ConcreteAbstract2 *ca2 = new ConcreteAbstract2(m);
    //让中介者认识两个具体的抽象类
    m->setConcreteMediator(ca1, ca2);

    ca1->Send("Hello");  //Output: ConcreteAbstract2 receive message: Hello   ---(From ConcreteAbstract1)
    ca2->Send("Hi");    //Output: ConcreteAbstract1 receive message: Hi   ---(From ConcreteAbstract2) 

    if(m != NULL){
        delete m;
        m = NULL;
    }
    if(ca1 != NULL){
        delete ca1;
        ca1 = NULL;
    }
    if(ca2 != NULL){
        delete ca2;
        ca2 = NULL;
    }

    return 0;
}