python 抽象类、抽象方法的实现

由于python 没有抽象类、接口的概念，所以要实现这种功能得abc.py 这个类库,具体方式如下

 1 from abc import ABCMeta, abstractmethod
 2 
 3 #抽象类
 4 class Headers(object):
 5     __metaclass__ = ABCMeta
 6 
 7     def __init__(self):
 8         self.headers = ''
 9 
10     @abstractmethod
11     def _getBaiduHeaders(self):pass
12 
13     def __str__(self):
14         return str(self.headers)
15 
16     def __repr__(self):
17         return repr(self.headers)
18 
19 #实现类
20 class BaiduHeaders(Headers):
21     def __init__(self, url, username, password):
22         self.url = url
23         self.headers = self._getBaiduHeaders(username, password)
24 
25     def _getBaiduHeaders(self, username, password):
26         client = GLOBAL_SUDS_CLIENT.Client(self.url)
27         headers = client.factory.create('ns0:AuthHeader')
28         headers.username = username
29         headers.password = password
30         headers.token = _baidu_headers['token']
31         return headers

如果子类不实现父类的_getBaiduHeaders方法,则抛出TypeError: Can't instantiate abstract class BaiduHeaders with abstract methods  异常

posted @ 2012-11-15 19:25  践道者  阅读(34148)  评论(0)  编辑  收藏  举报