code: public static Properties parseJSON(String json) {
      try {
        return utilsImpl.parseJSON(json);
      } catch (Exception e) {
        if (!GWT.isProdMode()) {
          System.err.println("Error while parsing json: " + e.getMessage() + ".\n" + json);
        }
        return Properties.create();
      }
    }
docs: Parses a json string returning a Object with useful method to get the
  content.