tuoheng_algN/test/设计模式/单例/demo5.py

22 lines
595 B
Python

from threading import RLock
class Singleton(object):
single_lock = RLock()
def __init__(self, name):
if hasattr(self, 'name'):
return
self.name = name
def __new__(cls, *args, **kwargs):
with Singleton.single_lock:
if not hasattr(Singleton, "_instance"):
Singleton._instance = object.__new__(cls)
return Singleton._instance
single_1 = Singleton('第1次创建')
single_2 = Singleton('第2次创建')
print(single_1.name, single_2.name) # 第2次创建 第2次创建
print(single_1 is single_2) # True