import java.net.URL;

public class Main {
   public static void main(String[] args) 
   throws Exception {
      URL url = new URL("https://www.twle.cn/yufei/html/html-basic-index.html");
      System.out.println("URL 是 " + url.toString());
      System.out.println("协议是 " + url.getProtocol());
      System.out.println("文件名是 " + url.getFile());
      System.out.println("主机是 " + url.getHost());
      System.out.println("路径是 " + url.getPath());
      System.out.println("端口号是 " + url.getPort());
      System.out.println("默认端口号是 " 
      + url.getDefaultPort());
   }
}

URL 是 https://www.twle.cn/yufei/html/html-basic-index.html
协议是 https
文件名是 /yufei/html/html-basic-index.html
主机是 www.twle.cn
路径是 /yufei/html/html-basic-index.html
端口号是 -1
默认端口号是 443