多项选择题
A.URL url=new URL("http","www.sina.com.cn/index.html",80);
B.URL url=new URL("http://www.sina.com.cn/index.html");
C.URL url=new URL("http","www.sina.com.cn",80,"index.html");
D.Url url=new URL("http","www.sina.com.cn/index.html");