docs: public static URL getURLForFile(String fileName) {
          URL url = null;
          if ( fileName != null ) {
              File file = new File( fileName );
              if ( file != null && file.exists() ) {
                  try {
                      url = file.toURL();
                  } catch ( MalformedURLException e ) {
                      throw new IllegalArgumentException( "file.toURL() failed for '" + file + "'" );
                  }
              }
          }
          return url;
      }