Python学习笔记--多进程和多线程

"""多进程和多线程"""
#  顺序执行
# from random import randint
# from time import time, sleep
#
#
# def download_task(filename):
#     print('开始下载%s...' % filename)
#     time_to_download = randint(5, 10)
#     sleep(time_to_download)
#     print('%s下载完成! 耗费了%d秒' % (filename, time_to_download))
#
#
# def main():
#     start = time()
#     download_task('Python从入门到住院.pdf')
#     download_task('Peking Hot.avi')
#     end = time()
#     print('总共耗费了%.2f秒.' % (end - start))
#
# # 开始下载Python从入门到住院.pdf...
# # Python从入门到住院.pdf下载完成! 耗费了10秒
# # 开始下载Peking Hot.avi...
# # Peking Hot.avi下载完成! 耗费了9秒
# # 总共耗费了19.02秒.
# if __name__ == '__main__':
#     main()


# 并行执行
# from multiprocessing import Process
# from os import getpid
# from random import randint
# from time import time, sleep
#
#
# def download_task(filename):
#     print('启动下载进程，进程号[%d].' % getpid())
#     print('开始下载%s...' % filename)
#     time_to_download = randint(5, 10)
#     sleep(time_to_download)
#     print('%s下载完成! 耗费了%d秒' % (filename, time_to_download))
#
# # #启动下载进程，进程号[9080].
# # 开始下载Peking Hot.avi...
# # 启动下载进程，进程号[12668].
# # 开始下载Python从入门到住院.pdf...
# # Python从入门到住院.pdf下载完成! 耗费了6秒
# # Peking Hot.avi下载完成! 耗费了8秒
# # 总共耗费了8.40秒.
# def main():
#     start = time()
#     p1 = Process(target=download_task, args=('Python从入门到住院.pdf', ))
#     p1.start()
#     p2 = Process(target=download_task, args=('Peking Hot.avi', ))
#     p2.start()
#     p1.join()
#     p2.join()
#     end = time()
#     print('总共耗费了%.2f秒.' % (end - start))
#
#
# if __name__ == '__main__':
#     main()

# 用多线程
# from random import randint
# from threading import Thread
# from time import time, sleep
#
#
# def download(filename):
#     print('开始下载%s...' % filename)
#     time_to_download = randint(5, 10)
#     sleep(time_to_download)
#     print('%s下载完成! 耗费了%d秒' % (filename, time_to_download))
#
#
# def main():
#     start = time()
#     t1 = Thread(target=download, args=('Python从入门到住院.pdf',))
#     t1.start()
#     t2 = Thread(target=download, args=('Peking Hot.avi',))
#     t2.start()
#     t1.join()
#     t2.join()
#     end = time()
#     print('总共耗费了%.3f秒' % (end - start))
# # 开始下载Python从入门到住院.pdf...
# # 开始下载Peking Hot.avi...
# # Peking Hot.avi下载完成! 耗费了5秒
# # Python从入门到住院.pdf下载完成! 耗费了9秒
# # 总共耗费了9.008秒
#
# if __name__ == '__main__':
#     main()

# 自定义多线程
from random import randint
from threading import Thread
from time import time, sleep


# class DownloadTask(Thread):
#
#     def __init__(self, filename):
#         super().__init__()
#         self._filename = filename
#
#     def run(self):
#         print('开始下载%s...' % self._filename)
#         time_to_download = randint(5, 10)
#         sleep(time_to_download)
#         print('%s下载完成! 耗费了%d秒' % (self._filename, time_to_download))
#
#
# def main():
#     start = time()
#     t1 = DownloadTask('Python从入门到住院.pdf')
#     t1.start()
#     t2 = DownloadTask('Peking Hot.avi')
#     t2.start()
#     t1.join()
#     t2.join()
#     end = time()
#     print('总共耗费了%.2f秒.' % (end - start))
#
# # 开始下载Python从入门到住院.pdf...
# # 开始下载Peking Hot.avi...
# # Peking Hot.avi下载完成! 耗费了5秒
# # Python从入门到住院.pdf下载完成! 耗费了10秒
# # 总共耗费了10.01秒.
# if __name__ == '__main__':
#     main()

from time import sleep
from threading import Thread,Lock


class Account(object):

    def __init__(self):
        self.lock = Lock()
        self._balance = 0

    def deposit(self, money):
        self.lock.acquire()
        try:
            # 计算存款后的余额
            new_balance = self._balance + money
            # 模拟受理存款业务需要0.01秒的时间
            sleep(0.01)
            # 修改账户余额
            self._balance = new_balance
            # self.lock.release()
        finally:
            self.lock.release()
    @property
    def balance(self):
        return self._balance


class AddMoneyThread(Thread):

    def __init__(self, account, money):
        super().__init__()
        self._account = account
        self._money = money


    def run(self):

        self._account.deposit(self._money)



def main():
    account = Account()
    threads = []
    # 创建100个存款的线程向同一个账户中存钱
    for _ in range(100):
        t = AddMoneyThread(account, 1)
        threads.append(t)
        t.start()
    # 等所有存款的线程都执行完毕
    for t in threads:
        t.join()
    print('账户余额为: ￥%d元' % account.balance)


if __name__ == '__main__':
    main()