Java URL：获取 URL 对象的根（删除路径）

Question

有没有办法从给定的URL.所以我的意思是，我想删除路径 url 段。URL aURL = new URL("http://example.com:80/docs/books/tutorial"                       + "/index.html?name=networking#DOWNLOADING");我一直在玩这个：System.out.println("protocol = " + aURL.getProtocol());System.out.println("authority = " + aURL.getAuthority());System.out.println("host = " + aURL.getHost());System.out.println("port = " + aURL.getPort());System.out.println("path = " + aURL.getPath());System.out.println("query = " + aURL.getQuery());System.out.println("filename = " + aURL.getFile());System.out.println("ref = " + aURL.getRef());输出是：protocol = httpauthority = example.com:80host = example.comport = 80path = /docs/books/tutorial/index.htmlquery = name=networkingfilename = /docs/books/tutorial/index.html?name=networkingref = DOWNLOADING我想得到的是一个新URL对象http://example.com:8080有任何想法吗？

Answer 1

我找到了更短的方法来维护除路径部分以外的所有内容，使用URI.resolve().

URL url = new URL("http://example.com:8081/api/test");

System.out.println(url)// prints "http://example.com:8081/api/test"

URL urlNoPath = url.resolve("/");

System.out.println(url)// prints "http://example.com:8081/"

Answer 2

只需使用URL构造函数来构建一个新的 URL。

URL newUrl = new URL(aURL.getProtocol(), aURL.getHost(), 8080, "/");