code: public static void main(String[] args) throws IOException, SAXException {
        if (args != null && args.length > 0) {
           validateXml(new URL(args[0]));
        } else {
           System.out.println(getXsd());
        }
     }
docs: prints xsd, or validate xml (no exceptions => ok)
  
  @param args
  @throws IOException