C++设计模式之单例模式(2)

/*
** FileName     : SingletonPatternDemo3
** Author       : Jelly Young
** Date         : 2013/11/20
** Description  : More information, please go to http://www.jb51.net
*/
 
#include <iostream>
using namespace std;
 
class Singleton
{
public:
    static Singleton *GetInstance()
    {
        return const_cast <Singleton *>(m_Instance);
    }
 
    static void DestoryInstance()
    {
        if (m_Instance != NULL )
        {
            delete m_Instance;
            m_Instance = NULL ;
        }
    }
 
    int GetTest()
    {
        return m_Test;
    }
 
private:
    Singleton(){ m_Test = 10; }
    static const Singleton *m_Instance;
    int m_Test;
};
 
const Singleton *Singleton ::m_Instance = new Singleton();
 
int main(int argc , char *argv [])
{
    Singleton *singletonObj = Singleton ::GetInstance();
    cout<<singletonObj->GetTest()<<endl;
    Singleton ::DestoryInstance();
}