Python多線程的幾種實現方式

Python threading模塊中Thread類經常使用的三種建立線程方法

• 建立Thread的實例，傳遞給它一個函數
• 建立Thread的實例，傳遞給它一個可調用的類實例
• 派生Thread的子類，並建立子類的實例

建立Thread的實例，傳遞給它一個函數

import threading
from time import ctime, sleep

loops = [4, 6]


def loop(nloop, nsec):
    print('start loop', nloop, 'at:', ctime())
    sleep(nsec)
    print('loop', nloop, 'done at:', ctime())

    
def main():
    print('starting at:', ctime())
    threads = []
    nloops = range(len(loops))

    for i in nloops:
        t = threading.Thread(target=loop, args=(i, loops[i]))
        threads.append(t)

    for i in nloops:
        threads[i].start()

    for i in nloops:
        threads[i].join()

    print('all done at:', ctime())

    
if __name__ == '__main__':
    main()

建立Thread的實例，傳遞給它一個可調用的類實例

import threading
from time import ctime, sleep

loops = [4, 2]


class ThreadFunc(object):
    def __init__(self, func, args, name=''):
        self.name = name
        self.func = func
        self.args = args

    def __call__(self, *args, **kwargs):
        self.func(*self.args)


def loop(nloop, nsec):
    print('start loop', nloop, 'at:', ctime())
    sleep(nsec)
    print('loop', nloop, 'done at:', ctime())


def main():
    print('starting at:', ctime())
    threads = []
    nloops = range(len(loops))

    for i in nloops:
        t = threading.Thread(target=ThreadFunc(loop, (i, loops[i]), loop.__name__))
        threads.append(t)

    for i in nloops:
        threads[i].start()

    for i in nloops:
        threads[i].join()

    print('all done at:', ctime())


if __name__ == '__main__':
    main()

派生Thread的子類，並建立子類的實例

import threading
from time import ctime,sleep

loops = [4, 2]


class MyThread(threading.Thread):
    def __init__(self, func, args, name=''):
        super().__init__()
        self.name = name
        self.func = func
        self.args = args

    def run(self):
        self.func(*self.args)


def loop(nloop, nsec):
    print('start loop', nloop, 'at:', ctime())
    sleep(nsec)
    print('loop', nloop, 'done at:', ctime())


def main():
    print('starting at:', ctime())
    threads = []
    nloops = range(len(loops))

    for i in nloops:
        t = MyThread(loop, (i, loops[i]), loop.__name__)
        threads.append(t)

    for i in nloops:
        threads[i].start()

    for i in nloops:
        threads[i].join()

    print('all done at:', ctime())


if __name__ == '__main__':
    main()