1 #include <iostream>
  2 using namespace std;
  3 
  4 #define SAFE_DELETE(p) if (p) { delete p; p = NULL; }
  5 
  6 class Mediator;
  7 
  8 class Colleague
  9 {
 10 public:
 11      Colleague(Mediator *pMediator) : m_pMediator(pMediator){}
 12 
 13      virtual void Send(wchar_t *message) = 0;
 14 
 15 protected:
 16      Mediator *m_pMediator;
 17 };
 18 
 19 class ConcreteColleague1 : public Colleague
 20 {
 21 public:
 22      ConcreteColleague1(Mediator *pMediator) : Colleague(pMediator){}
 23 
 24      void Send(wchar_t *message);
 25 
 26      void Notify(wchar_t *message)
 27      {
 28           wcout<<message<<endl;
 29      }
 30 };
 31 
 32 class ConcreteColleague2 : public Colleague
 33 {
 34 public:
 35      ConcreteColleague2(Mediator *pMediator) : Colleague(pMediator){}
 36 
 37      void Send(wchar_t *message);
 38 
 39      void Notify(wchar_t *message)
 40      {
 41           cout<<"ConcreteColleague2 is handling the message."<<endl;
 42           wcout<<message<<endl;
 43      }
 44 };
 45 
 46 class Mediator
 47 {
 48 public:
 49      virtual void Sent(wchar_t *message, Colleague *pColleague) = 0;
 50 };
 51 
 52 class ConcreteMediator : public Mediator
 53 {
 54 public:
 55      // The mediator forward the message
 56      void Sent(wchar_t *message, Colleague *pColleague)
 57      {
 58           ConcreteColleague1 *pConcreteColleague1 = 
                     dynamic_cast<ConcreteColleague1 *>(pColleague);
 59           if (pConcreteColleague1)
 60           {
 61                cout<<"The message is from ConcreteColleague1. "
                      <<"Now mediator forward it to ConcreteColleague2"<<endl;
 62                if (m_pColleague2)
 63                {
 64                     m_pColleague2->Notify(message);
 65                }
 66           }
 67           else
 68           {
 69                if (m_pColleague1)
 70                {
 71                     m_pColleague1->Notify(message);
 72                }
 73           }
 74      }
 75 
 76      void SetColleague1(Colleague *pColleague)
 77      {
 78           m_pColleague1 = dynamic_cast<ConcreteColleague1 *>(pColleague);
 79      }
 80 
 81      void SetColleague2(Colleague *pColleague)
 82      {
 83           m_pColleague2 = dynamic_cast<ConcreteColleague2 *>(pColleague);
 84      }
 85 
 86 private:
 87      // The Mediator knows all the Colleague
 88      ConcreteColleague1 *m_pColleague1;
 89      ConcreteColleague2 *m_pColleague2;
 90 };
 91 
 92 void ConcreteColleague1::Send(wchar_t *message)
 93 {
 94      // The second parameter mark where the message comes from
 95      m_pMediator->Sent(message, this);
 96 }
 97 
 98 void ConcreteColleague2::Send(wchar_t *message)
 99 {
100      m_pMediator->Sent(message, this);
101 }
102 
103 int main()
104 {
105      // Create the mediator
106      Mediator *pMediator = new ConcreteMediator();
107 
108      Colleague *pColleague1 = new ConcreteColleague1(pMediator);
109      Colleague *pColleague2 = new ConcreteColleague2(pMediator);
110 
111      ConcreteMediator *pConcreteMediator = dynamic_cast<ConcreteMediator *>(pMediator);
112      pConcreteMediator->SetColleague1(pColleague1);
113      pConcreteMediator->SetColleague2(pColleague2);
114 
115      wchar_t message[260] = L"Where are you from?";
116      pColleague1->Send(message);
117 
118      return 0;
119 }