如果多个线程共同对某个数据修改访问，为了保证数据的正确性，需要对多个线程进行同步。
使用Thread对象的Lock和Rlock可以实现简单的线程同步，
acquire:请求锁,成功则返回true.
release:释放锁.
对于需要每次只允许一个线程操作的数据，可以使用上述锁来实现互斥访问。
代码示例如下:
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| #!/usr/bin/python
import threading
import time
class QThread (threading.Thread):
""" QThread class"""
def __init__(self, threadID, name, counter):
threading.Thread.__init__(self)
self.threadID = threadID
self.name = name
self.counter = counter
def run(self):#线程的run函数
print "%s running" % self.name
# 获得锁，成功获得锁定后返回True
# 可选的timeout参数不填时将一直阻塞直到获得锁定
# 否则超时后将返回False
threadLock.acquire()
showThreadMessage(self.name, self.counter, 3)
# 释放锁
threadLock.release()
def showThreadMessage(threadName, delay, counter):
while counter > 0:
time.sleep(delay)
print "%s showThreadMessage" % (threadName)
counter -= 1
threadLock = threading.Lock()
threads = []
# 创建新线程
thread1 = QThread(1, "KSnow", 1)
thread2 = QThread(2, "KAir", 2)
# 线程开始执行
thread1.start()
thread2.start()
# 添加线程到线程列表
threads.append(thread1)
threads.append(thread2)
# 等待所有线程完成
for t in threads:
t.join()
print "Exiting From Main Thread"
|
运行情况如下:
ksnowlv@ksnowlvdeMacBook-Pro~/Documents/lvwei projects/python$python thread_synchronization.py
KSnow running
KAir running
KSnow showThreadMessage
KSnow showThreadMessage
KSnow showThreadMessage
KAir showThreadMessage
KAir showThreadMessage
KAir showThreadMessage
Exiting From Main Thread