Question

我有一个线程列表。以下代码使用'with'语句释放块末尾的互斥锁。这非常有用，因为它允许用户循环遍历每个线程并选择停止它或使其保持运行。

import threading

#subclass with state
class Mythread(threading.Thread):
    def __init__(self,myId, astr, mutex):
        self.myId = myId
        self.astr = astr
        self.mutex = mutex
        threading.Thread.__init__(self)
    def run(self):
        while True:
            with self.mutex:
                print('[%s] => %s' % (self.myId, self.astr))
                ans=raw_input("Enter s to stop thread...")
                if ans == 's':
                    break

stdoutmutex = threading.Lock()
threads = []

for i,j in zip(range(7),['A', 'B', 'C','D','E','F','G']):
    thread = Mythread(i,j,stdoutmutex)
    thread.start()
    threads.append(thread)

for thread in threads:
    thread.join()

为了确保线程按照'threads'列表中的顺序循环，我使用了Queue模块来控制线程锁的顺序：

thread = q.get()
with thread.mutex:

修改过的脚本：

import threading, Queue

#subclass with state
class Mythread(threading.Thread):
    def __init__(self,myId, astr, mutex):
        self.myId = myId
        self.astr = astr
        self.mutex = mutex
        threading.Thread.__init__(self)
    def run(self):
        while True:
            thread = q.get()
            with thread.mutex:
                print('[%s] => %s' % (self.myId, self.astr))
                ans=raw_input("Enter s to stop thread...")
                if ans == 's':
                    q.task_done()
                    break
                else:
                    q.put(thread)


stdoutmutex = threading.Lock()
threads = []

q = Queue.Queue()

for i,j in zip(range(7),['A', 'B', 'C','D','E','F','G']):
    thread = Mythread(i,j,stdoutmutex)
    threads.append(thread)

for thread in threads:
    q.put(thread)
    thread.start()

for thread in threads:
    thread.join()

这似乎与正确的线程顺序A，B，C ...一起发送到标准输出。但是，是否可以验证队列是否有效并且这不仅仅是巧合？

具有队列有序线程的互斥锁

0 个答案: