#!/usr/bin/python # -*- coding: UTF-8 -*- import Queue import threading import time exitFlag = 0 class myThread (threading.Thread): def __init__(self, threadID, name, q): threading.Thread.__init__(self) self.threadID = threadID self.name = name self.q = q def run(self): print "Starting " + self.name process_data(self.name, self.q) print "Exiting " + self.name def process_data(threadName, q): while not exitFlag: queueLock.acquire() if not workQueue.empty(): data = q.get() queueLock.release() print "%s processing %s" % (threadName, data) else: queueLock.release() time.sleep(1) threadList = ["Thread-1", "Thread-2", "Thread-3"] nameList = ["One", "Two", "Three", "Four", "Five"] queueLock = threading.Lock() workQueue = Queue.Queue(10) threads = [] threadID = 1 # 创建新线程 for tName in threadList: thread = myThread(threadID, tName, workQueue) thread.start() threads.append(thread) threadID += 1 # 填充队列 queueLock.acquire() for word in nameList: workQueue.put(word) queueLock.release() # 等待队列清空 while not workQueue.empty(): pass # 通知线程是时候退出 exitFlag = 1 # 等待所有线程完成 for t in threads: t.join() print "Exiting Main Thread"
这段代码中结尾为什么要用
for t in threads: t.join()
这样写呢?我试过把这两行代码注释,好像运行也很正常啊
join 主要用于进程/线程之间的协同,其功能在于等待目的进程/线程执行完毕。
在此,因为你的线程操作很简单,功能函数执行完成后线程就结束了。join与否就显得区别不大。
如果主线程需要获取子线程的状态就join;注释掉运行,那就是主线程不需要获取子线程状态了,当然也是可以正常运行的。
参考:https://docs.python.org/2/lib...