How to disconnect jsmpp connection while using auto reconnect

Question

I have developed an application using jsmpp library. I used the auto-reconnect class to make the application auto-connect but when I try to use unbindAndClose() it sends null to #private SMPPSession session = null; ......so the system still do auto-reconnect how to forcefully unbind the system

 JButton btnDisconnecct = new JButton("Disconnecct");
    btnDisconnecct.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent e) {
            session.unbindAndClose();
            execService.shutdown();
        }
    });
    btnDisconnecct.setBounds(170, 26, 129, 25);
    panel.add(btnDisconnecct);