private void leerProperties() {
        FileReader fr = null;
        Properties p;
        try {
            p = new Properties();
            fr = new FileReader(Constantes.properties);
            p.load(fr);
            rutaBD = p.getProperty(Constantes.rutaFicheros);
        } catch (FileNotFoundException ex) {
           Logger.getLogger(Ventana.class.getName()).log(Level.SEVERE, null, ex);
            
        } catch (IOException ex) {
            Logger.getLogger(Ventana.class.getName()).log(Level.SEVERE, null, ex);
        } finally {
            if (fr != null) {
                try {
                    fr.close();
                } catch (IOException ex) {
                    Logger.getLogger(Ventana.class.getName()).log(Level.SEVERE, null, ex);
                }
            }
        }
    }