Add checkbox for runtime object

i want to add checkbox for runtime object(c: drive files and folder). Here i attached my code.

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import java.io.*;
import java.util.zip.CheckedInputStream;

public class MyTree extends JFrame implements ActionListener{

File[] rt;
File drive;
private DefaultComboBoxModel comboModel;

MyTreeModel model;
File root = null;
JTree tree;

public MyTree() {

initComponents();

}

public void initComponents() {

setLayout(new BorderLayout());
setDefaultCloseOperation(javax.swing.WindowConstants.DISPOSE_ON_CLOSE);

panelB = new javax.swing.JPanel();
panelB.setLayout(new BorderLayout());

comboModel = new DefaultComboBoxModel();
selectDrive = new JComboBox(comboModel);

rt=File.listRoots();

for (int i=0; i