Question

How can I better write the following class? For example is there a nice way to slip having the two flags is_alive and is_finished?

Monitor(threading.Thread):
    def run(self):
        resource = Resource("com1")

        self.alive = True
        self.is_finished = False
        try:
            while self.alive:
                pass # use resource
        finally:
            resource.close()
            self.is_finished = True    

    def stop(self):
        self.alive = False
        while not self.is_finished:
            time.sleep(0.1)

Answer 1

That’s pretty much it. However, you don’t need the is_finished, because you can use the join() method:

Monitor(threading.Thread):
    def run(self):
        resource = Resource("com1")

        self.alive = True
        try:
            while self.alive:
                pass # use resource
        finally:
            resource.close()

    def stop(self):
        self.alive = False
        self.join()

If you do need to find if a thread is running, you can call mythread.is_alive() – you don’t need to set this yourself.