DEADcat_12: https://word-to-markdown.herokuapp.com/没了（大哭）

nacrt: 从ConcurrentHashMap他自己的作者（Doug Lea）： http://cs.oswego.edu/pipermail/concurrency-interest/2006-May/002485.html The main reason that nulls aren't allowed in ConcurrentMaps (ConcurrentHashMaps, ConcurrentSkipListMaps) is that ambiguities that may be just barely tolerable in non-concurrent maps can't be accommodated. The main one is that if map.get(key) returns null, you can't detect whether the key explicitly maps to null vs the key isn't mapped. In a non-concurrent map, you can check this via map.contains(key), but in a concurrent one, the map might have changed between calls. ConcurrentMaps（ConcurrentHashMaps，ConcurrentSkipListMaps）不允许使用null的主要原因是，无法容纳在非并行映射中几乎无法容忍的歧义。最主要的是，如果map.get(key)return null，则无法检测到该键是否显式映射到null该键。在非并行映射中，您可以通过进行检查 map.contains(key)，但在并行映射中，两次调用之间的映射可能已更改

zhang__8626 回复 一只快乐的野指针吼: 如果在本地运行只能局域网访问，如果放在服务器上运行，浏览器输入服务器公网IP所有人都可见

weixin_38525647: 您好，我在最后一步的代码出了问题，显示： 存放数据地址有误 该用户原创微博中不存在图片 Traceback (most recent call last): File "E:/weibo Project/weibo.py", line 128, in print(u'原创微博爬取完毕，共%d条，保存路径%s'%(word_count - 3,word_path)) NameError: name 'word_path' is not defined 请问是怎么回事？

一只快乐的野指针吼: 这个是当前局域网可以访问，还是所有人都能访问？