singleton 的实例分析

#include <iostream>

using namespace std;

class Singleton

{

private:

Singleton();

public:

static Singleton *GetInstance();

virtual ~Singleton();

public:

static Singleton *instance;

};

Singleton *Singleton::instance = NULL;

Singleton ::Singleton()

{

}

Singleton *Singleton::GetInstance()

{

if(instance == NULL)

{

instance = new Singleton();

}

return instance;

}

Singleton::~Singleton()

{

}

int main(int argc, char* argv[])

{

Singleton *test = Singleton::GetInstance();

Singleton *test1 = Singleton::GetInstance();

if(test == test1)

{

cout<< "the same instance!" << endl;

}

        delete test;

        test = NULL;

return 0;

}