code: public static Resource newResource(URL url)
          throws IOException
      {
          if (url==null)
              return null;
  
          String urls=url.toExternalForm();
          if( urls.startsWith( "file:"))
          {
              try
              {
                  FileResource fileResource= new FileResource(url);
                  return fileResource;
              }
              catch(Exception e)
              {
                  log.debug(LogSupport.EXCEPTION,e);
                  return new BadResource(url,e.toString());
              }
          }
          else if( urls.startsWith( "jar:file:"))
          {
              return new JarFileResource(url);
          }
          else if( urls.startsWith( "jar:"))
          {
              return new JarResource(url);
          }
  
          return new URLResource(url,null);
      }
docs: Construct a resource from a url.
  @param url A URL.
  @return A Resource object.