將對象封裝在類似中介的類中，對象之間的通信他們本身不用關心

mediator.h

#ifndef _MEDIATOR_H

#define _MEDIATOR_H

#include <iostream>

#include <string>

using namespace std;

class Mediator

{

public:

Mediator() {

}

~Mediator() {

}

virtual void DoActionFromAtoB()=0;

virtual void DoActionFromBtoA()=0;

};

class Colleage

{

public:

virtual ~Colleage() {

}

virtual void Action()=0;

Colleage() {

}

Colleage(Mediator* mdt) : _mdt(mdt) {

}

public:

Mediator* _mdt;

string _sdt;

};

class ConcreteColleageA : public Colleage

{

public:

ConcreteColleageA() {

}

ConcreteColleageA(Mediator* mdt) : Colleage(mdt) {

}

~ConcreteColleageA() {

}

void Action() {

_mdt->DoActionFromAtoB();

cout << "state of concreteColleageA:" << _sdt << endl;

}

public:

string _sdt;

};

class ConcreteColleageB : public Colleage

{

public:

ConcreteColleageB() {

}

ConcreteColleageB(Mediator* mdt) : Colleage(mdt) {

}

~ConcreteColleageB() {

}

void Action() {

_mdt->DoActionFromBtoA();

cout << "state of concreteColleageB:" << _sdt << endl;

}

public:

string _sdt;

};

class ConcreteMediator : public Mediator

{

public:

ConcreteMediator() {

}

~ConcreteMediator() {

}

ConcreteMediator(Colleage* clgA, Colleage* clgB) : _clgA(clgA), _clgB(clgB) {

}

void DoActionFromAtoB() {

_clgB->_sdt = _clgA->_sdt;

}

void DoActionFromBtoA() {

_clgA->_sdt = _clgB->_sdt;

}

void IntroColleage(Colleage* clgA, Colleage* clgB) {

_clgA = clgA;

_clgB = clgB;

}

public:

Colleage* _clgA;

Colleage* _clgB;

};

#endif // _MEDIATOR_H

mediator.cpp

#include "mediator.h"

int main()

{

ConcreteMediator* m = new ConcreteMediator;

ConcreteColleageA* c1 = new ConcreteColleageA(m);

ConcreteColleageB* c2 = new ConcreteColleageB(m);

m->IntroColleage(c1, c2);

c1->_sdt = "old";

c2->_sdt = "old";

c1->Action();

c2->Action();

c1->_sdt = "new";

c1->Action();

c2->Action();

c2->_sdt = "old";

c2->Action();

c1->Action();

return 0;

}

編譯: make?mediator