1、懒汉式
2、饿汉式
3、加锁
4、双重加锁
5、智能指针
6、模板
template <typename T>
class Singleton
{
public:
static T& getInstance()
{
init();
return instance;
}
~Singleton(){}
private :
static void init()
{
if(0 == instance)
{
instance = new T;
atexit(destroy);//注册destroy函数，当程序结束时，自动调用destroy函数
}
}
static void destroy()
{
delete instance;
}
Singleton(){}
Singleton(const T& other){}
Singleton& operator=(cosnt T& other){}
static T* instance;
}
template<typename T>
T* Singleton<T>::instance = 0;