CodeIQ 用問題

clock.py

# -*- coding: utf-8 -*-

import sys
import time
import datetime
 
class Observable():

    def __init__(self):
        self.__observers = []
        self.__state     = False

    def is_changed (self):
        return self.__state

    def changed (self):
        self.__state = True

    def notify_observers (self, args):

        if not self.is_changed():
            return

        self.__state = False

        for observer in self.__observers:
            try:
                observer.update(args)
            except Exception, inst:
                print type(inst)
                print inst.args
                print inst

    def add_observer(self, obj):
        self.__observers.append(obj)

 
class Tick(Observable):
    def start (self):
        while True:
            now = datetime.datetime.now()
 
            self.changed()
            self.notify_observers([now.hour, now.minute, now.second])
 
            time.sleep( 1.0 - (datetime.datetime.now().microsecond / 1000000.0) )


class TextClock():
    def update(self, time):
        sys.stdout.write( "\r%02d:%02d:%02d" % tuple(time) )
        sys.stdout.flush()


if __name__ == '__main__':
    tick = Tick()
    tick.add_observer( TextClock() )
    tick.start()