// Entity Resolver
  public InputSource resolveEntity(String publicId, String systemId) throws SAXException {

    if (er != null) {
      try {
        return er.resolveEntity(publicId, systemId);
      } catch (IOException e) {
        System.out.println("resolveEntity threw IOException!");
        return null;
      }
    } else {
      return null;
    }
  }