多线程实现单例模式
http://www.cnblogs.com/huchong/p/8244279.html
代码:
import threading def synchronized(func): func.__lock__ = threading.Lock() def lock_func(*args, **kwargs): with func.__lock__: return func(*args, **kwargs) return lock_func class Singleton(object): instance = None @synchronized def __new__(cls, *args, **kwargs): """ :type kwargs: object """ if cls.instance is None: cls.instance = super().__new__(cls) return cls.instance def __init__(self, num): self.a = num + 5 def printf(self): print(self.a) a = Singleton(3) print(id(a)) b = Singleton(4) print(id(b))