DesignPattern/06.Singleton/2.Code/Singleton/Singleton.h

50 lines
932 B
C++

#ifndef __SINGLETON_H__
#define __SINGLETON_H__
#include <iostream>
#include <string.h>
#include <mutex>
using namespace std;
class Singleton_Lazy
{
public:
static Singleton_Lazy* getInstance(){
printf("This is Singleton Lazy mode...\n");
if (instance == NULL){
m_mutex.lock();
if (instance == NULL){
printf("创建新的实例\n");
instance = new Singleton_Lazy();
}
m_mutex.unlock();
}
return instance;
}
private:
Singleton_Lazy(){}
static Singleton_Lazy* instance;
static std::mutex m_mutex;
};
Singleton_Lazy* Singleton_Lazy::instance = NULL;
std::mutex Singleton_Lazy::m_mutex;
class Singleton_Hungry
{
public:
static Singleton_Hungry* getInstance()
{
printf("This Singleton Hungry mode...\n");
return instance;
}
private:
Singleton_Hungry() {}
static Singleton_Hungry* instance;
};
Singleton_Hungry* Singleton_Hungry::instance = new Singleton_Hungry;
#endif //__SINGLETON_H__