""" __author__ = 王梁旭"""
import time
from threading import Thread, Lock

"""
多線程模擬銀行到賬操作:一百個賬戶同時轉(zhuǎn)賬到賬戶(操作存在延遲)
(由于系統(tǒng)存在延遲,在系統(tǒng)睡眠時,其它線程會調(diào)用數(shù)據(jù),使結(jié)果被未知次覆蓋,
最后不能得到正確的數(shù)據(jù))
(給數(shù)據(jù)加線程鎖,保證一個數(shù)據(jù)一把鎖,會使數(shù)據(jù)調(diào)用變得像排隊一樣,
一個數(shù)據(jù)調(diào)用結(jié)束后開鎖后才能被下一個線程調(diào)用)
"""


class Account:
    """
    賬戶類
    """
    def __init__(self):
        self.balance = 0.0
        self.lock = Lock()

    def deposit(self, money):
        # 給線程加鎖
        with self.lock:
            new_balance = self.balance + money
            time.sleep(0.001)  # 模擬延遲
            self.balance = new_balance
        # with 之后自動解鎖

def main():
    """
    多線程創(chuàng)建一百個賬戶轉(zhuǎn)賬進入賬戶
    :return: 0
    """
    account = Account()
    threads = []
    for _ in range(100):
        # 起一個線程對象
        t = Thread(target=account.deposit, args=(1,))
        # 將線程對象存入列表
        threads.append(t)
        # 開啟線程
        t.start()
    for t in threads:
        # 線程對象加 join() ,執(zhí)行該對象完之后在執(zhí)行后面的方法
        t.join()
    print(account.balance)


if __name__ == '__main__':
    main()