并发编程--进程池与线程池-练习3

通过继承multipocessing类，实现一个进程池。

代码如下：

# coding = utf-8
'''
实现一个进程池
'''
import time
import multiprocessing
from multiprocessing import Manager, Queue

class MyProcess(object):
    def __init__(self, num):
        super().__init__()

        # self.queue = Manager().Queue()
        self.queue = multiprocessing.JoinableQueue()

        for i in range(1, num+1):
            multiprocessing.Process(target=self.work, daemon=True).start()

    def work(self):
        '''
        从队列获取任务并执行
        :return:
        '''
        while True:
            try:
                func, args, kwargs = self.queue.get()
                func(*args, **kwargs)
            except Exception as e:
                print(e)
            finally:
                self.queue.task_done()

    def apply_async(self, func, args=(), kwargs={}):
        '''
        接收任务，并将其存入到队列中
        :param func:
        :param args:
        :param kwargs:
        :return:
        '''
        self.queue.put((func, args, kwargs))

    def join(self):
        '''
        控制进程结束
        :return:
        '''
        self.queue.join()
def func1():
    print('111')
    time.sleep(2)
def func2():
    print('222')
    time.sleep(2)
def func3():
    print('333')
if __name__ == '__main__':
    process = MyProcess(2)
    process.apply_async(func1)
    process.apply_async(func2)
    process.apply_async(func3)
    process.join()
    print('任务结束！')