public int numEsta(String estacion) {
        File file = null;
        FileReader reader = null;
        BufferedReader bf = null;
        int num_esta = 999;
        try {
            file = new File(getEsta_ref());
            reader = new FileReader(file);
            bf = new BufferedReader(reader);
            String line = "";
            String[] aux_line;
            boolean encontrado = false;
            while ((line = bf.readLine()) != null && !encontrado) {
                aux_line = line.trim().split(" ");
                if (aux_line[1].trim().equals(estacion)) {
                    encontrado = true;
                    num_esta = Integer.parseInt(aux_line[0].trim());
                }
            }
        } catch (FileNotFoundException ex) {
            Logger.getLogger(Estaciones.class.getName()).log(Level.SEVERE, null, ex);
        } catch (IOException ex) {
            Logger.getLogger(Estaciones.class.getName()).log(Level.SEVERE, null, ex);
        }
        return num_esta;
    }