public void endElement(String uri, String localName, String qName) throws SAXException {
          switch (qName) {
               case "config": {
            	   configList.add(getConfig());
                   break;
               }
               case "population": {
            	   getConfig().setPopulation(Integer.parseInt(text));
            	   break;
               }
               case "mutationRate": {
            	   getConfig().setMutationRate(Integer.parseInt(text));
            	   break;
               }
               case "vueltas": {
            	   getConfig().setVueltas(Integer.parseInt(text));
            	   break;
               }
          }
     }