验证URL地址 @param url 格式：http://blog.csdn.net:80/xyang81/article/details/7705960? 或 http://www.csdn.net:80 @return 验证成功返回true，验证失败返回false
(String url)
source not stored for this graph (policy: none)
nothing calls this directly
no outgoing calls
no test coverage detected