code: public synchronized Document readPolicy(URL url)
              throws ParsingException {
          try {
              return readPolicy(url.openStream());
          } catch (IOException ioe) {
              throw new ParsingException("Failed to resolve the URL: "
                      + url.toString(), ioe);
          }
      }
docs: Tries to read an XACML policy or policy set based on the given URL. This
  may be any resolvable URL, like a file or http pointer.
  
  @param url
  a URL pointing to the policy to read
  @return a (potentially schema-validated) policy loaded from the given
  file
  @throws ParsingException
  if an error occurs while reading or parsing the policy, or if the
  URL can't be resolved