Python单例模式

#
#   py_singleton.py
#   py_learn
#
#   Created by Z. Steve on 2023/8/8 09:45.
#


# # 查看对象地址 demo
# class Utility:
#     pass
#
#
# u1 = Utility()
# u2 = Utility()
#
# # 输出发现 u1 、 u2 两个对象的地址不一样
# print(u1)
# print(id(u1))
# print(u2)
# print(id(u2))


# 单例模式
class Utility:
    def say_hello(self):
        print("hello world.")


# 其他地方需要使用 Utility 类的对象时，通过调用 tool 属性就永远获取的是同样的对象
tool = Utility()









#
#   py_singleton_test.py
#   py_learn
#
#   Created by Z. Steve on 2023/8/8 10:01.
#

import py_singleton


utility = py_singleton.tool
utility2 = py_singleton.tool

utility.say_hello()
utility2.say_hello()

print(utility)
print(id(utility))
print(utility2)
print(id(utility2))