Message does not appear in the taskbar java

My question is how can I get a msg from the taskbar by calling my method MessageTrayIcon () from another class? I mean, I call it but I do not do any action, msj does not appear in my taskbar, I have a Timer that fires every X seconds, msj should check if there is something to show that appears in the notification bar but that do not do anything.

I have my MessageTrayIcon method that is in my class notification.

    public class Notificacion {

    private JFrame parent;
    private PopupMenu popup = new PopupMenu();
    private final Image image = new ImageIcon(getClass().getResource("notificaciones.png")).getImage();
    private final TrayIcon trayIcon = new TrayIcon(image, "Notificacion.png", popup);
    //para el Timer
    private Timer timer;
    ///////////////////////////
    SystemTray systemTray;

    public Notificacion() {
    }

    public void instanciarTray() {
        trayIcon.setImageAutoSize(true);
        systemTray = SystemTray.getSystemTray();
    }

    public void segundoPlano() {
        try {
            if (SystemTray.isSupported()) {
                systemTray.add(trayIcon);

                //Se inicia una tarea cuando se minimiza           
                if (timer != null) {
                    timer.cancel();
                }
                timer = new Timer();
                timer.schedule(new miTimerTask(), 2000, 5000);//Se ejecuta cada 5 segundos
            }
        } catch (Exception e) {
            JOptionPane.showMessageDialog(null, e.getMessage(), "Error", JOptionPane.ERROR);
        }
    }

//    Muestra una burbuja con la accion que se realiza
    public void MensajeTrayIcon(String texto, MessageType tipo) {
        trayIcon.displayMessage("Advertencia.", texto, tipo);
        System.out.println("pasa por aqui");
    }
}

This method is called from another class which does a series of things which compares if it finds matches between the contents of a Map and a arraylist should show a msg in the notification bar in the case that it has something to show but he does not.

    public class LeerArchivos {

    Notificacion notificacion = new Notificacion();
    ArrayList<String> keyArray = new ArrayList<>();

    public void leer(ArrayList<String> arrayList) {
        Map<String, String> mapaCodigosArchivo = new HashMap();

        try {
            // Abrimos el archivo con la ruta especificada.
            FileInputStream fstream = new FileInputStream(new File("Sucursales.txt"));
            // Creamos el objeto de entrada
            DataInputStream entrada = new DataInputStream(fstream);
            // Creamos el Buffer de Lectura
            BufferedReader buffer = new BufferedReader(new InputStreamReader(entrada));
            String contenido;
            // Leer el archivo linea por linea
            while ((contenido = buffer.readLine()) != null) {
                String[] separador = contenido.split(",");
                mapaCodigosArchivo.put(separador[0], separador[1]);
            }
            keyArray.clear();
            //Recorremos el arrayList
            for (String nombreArchivo : arrayList) {
                String[] separador = nombreArchivo.split("_");
                String codSucursal = separador[0].replace("PDA", "").trim();
                keyArray.add(codSucursal);
            }
            for (String key : mapaCodigosArchivo.keySet()) {
                int encontrados = this.contarTicketPorSucursal(keyArray, key);
                if (encontrados > 0) {
                    notificacion.MensajeTrayIcon("Tienes " + encontrados + " ticket pendiente de la sucursal: " + mapaCodigosArchivo.get(key), MessageType.INFO);
//                    System.out.println("Tienes " + encontrados + " ticket pendiente de la sucursal: " + mapaCodigosArchivo.get(key));
                }
            }
            // Cerramos el archivo
            entrada.close();
        } catch (Exception e) { //Catch de excepciones
            System.err.println("Ocurrio un error: " + e.getMessage());
        }
    }

    private int contarTicketPorSucursal(ArrayList<String> keyArray, String key) {
        int contador = 0;
        for (int i = 0; i < keyArray.size(); i++) {
            if (keyArray.get(i).equals(key)) {
                contador++;
            }
        }
        return contador;
    }
}

If I debug the MessageTrayIcon method by printing it on the screen, it calls it, it goes through the cod but it does not appear in the taskbar, I mean? How could I make it so that I said msj ..

Thank you very much for your help.