code: public List<IIsotope> readIsotopes() {
          List<IIsotope> isotopes = new ArrayList<IIsotope>();
          try {
              parser.setFeature("http://xml.org/sax/features/validation", false);
              logger.info("Deactivated validation");
          } catch (SAXException exception) {
              logger.warn("Cannot deactivate validation: ", exception.getMessage());
              logger.debug(exception);
          }
          IsotopeHandler handler = new IsotopeHandler(builder);
          parser.setContentHandler(handler);
          try {
              parser.parse(new InputSource(input));
              isotopes = handler.getIsotopes();
          } catch (IOException exception) {
              logger.error("IOException: ", exception.getMessage());
              logger.debug(exception);
          } catch (SAXException saxe) {
              logger.error("SAXException: ", saxe.getClass().getName());
              logger.error(saxe.getMessage());
              logger.debug(saxe);
          }
          return isotopes;
      }
docs: Triggers the XML parsing of the data file and returns the read Isotopes.
  It turns of XML validation before parsing.
  
  @return a List of Isotope's. Returns an empty list is some reading error
  occurred.