设计模式（二）观察者监听者模式

基于MAP线程安全的观察者监听者模式

#include<map>  
#include<string>  
#include<vector>  
#include<iostream>  
#include<memory>  
using namespace std;  
  
class Listener  
{  
public:  
    Listener(string name):_name(name){}  
    virtual void handleMessage(int msgid) = 0;  
    string _name;  
};  
  
class Listener1 : public Listener  
{  
public:  
    Listener1(string name):Listener(name){}  
    void handleMessage(int msgid)  
    {  
        cout<<_name<<" ";  
        switch(msgid)  
        {  
        case 0:  
            cout<<"handle 0 msg!"<<endl;  
            break;  
        case 1:  
            cout<<"handle 1 msg!"<<endl;  
            break;  
        default:  
            cout<<"recv invalid msg!"<<endl;  
            break;  
        }  
    }  
};  
  
class Listener2 : public Listener  
{  
public:  
    Listener2(string name):Listener(name){}  
    void handleMessage(int msgid)  
    {  
        cout<<_name<<" ";  
        switch(msgid)  
        {  
        case 0:  
            cout<<"handle 0 msg!"<<endl;  
            break;  
        case 2:  
            cout<<"handle 2 msg!"<<endl;  
            break;  
        default:  
            cout<<"recv invalid msg!"<<endl;  
            break;  
        }  
    }  
};  
  
class Listener3 : public Listener  
{  
public:  
    Listener3(string name):Listener(name){}  
    void handleMessage(int msgid)  
    {  
        cout<<_name<<" ";  
        switch(msgid)  
        {  
        case 1:  
            cout<<"handle 1 msg!"<<endl;  
            break;  
        case 3:  
            cout<<"handle 3 msg!"<<endl;  
            break;  
        default:  
            cout<<"recv invalid msg!"<<endl;  
            break;  
        }  
    }  
};  
  
class Observer  
{  
public:  
    void registerMsg(weak_ptr<Listener> plistener,int msgid)  
    {  
        map<int,vector<weak_ptr<Listener>>>::iterator it = _obserMap.find(msgid);  
        if(it == _obserMap.end())  
        {  
            vector<weak_ptr<Listener>> vec;  
            vec.push_back(plistener);  
            _obserMap.insert (make_pair(msgid,vec));  
        }  
        else  
        {  
            it->second.push_back(plistener);   
        }  
    }  
  
   void dispatchMsg(int msgid)  
    {  
        map<int,vector<weak_ptr<Listener>>>::iterator it = _obserMap.find(msgid);  
        if(it!=_obserMap.end())  
        {  
            vector<weak_ptr<Listener>>::iterator vit = it->second.begin();  
            for(;vit!=it->second.end();++vit)  
            {  
                //(*vit)->handleMessage(msgid);  
                shared_ptr<Listener> p = (*vit).lock();//提升  
                if(p != NULL)  
                {  
                    p->handleMessage(msgid);  
                }  
            }  
        }  
    }  
private:  
    map<int,vector<weak_ptr<Listener>>> _obserMap;  
};  
  
Observer obser;  
int main()  
{  
    //监听者线程  
    shared_ptr<Listener> p1(new Listener1("Listener1"));  
    shared_ptr<Listener> p2(new Listener2("Listener2"));  
    shared_ptr<Listener> p3(new Listener3("Listener3"));  
  
    //Observer obser;   
  
    obser.registerMsg(p1,0);  
    obser.registerMsg(p1,1);  
    obser.registerMsg(p2,0);  
    obser.registerMsg(p2,2);  
    obser.registerMsg(p3,1);  
    obser.registerMsg(p3,3);  
  
    //观察者线程  
    int msgid = 0;  
    while(true)  
    {  
        cout<<"msgid :";  
        cin>>msgid;  
  
        obser.dispatchMsg(msgid);  
    }  
    return 0;  
}