How do you dispose a thread-handled modal dialog not thru some actions?

Question

The code almost looks like this:
/* Thread that disposes the dialog when the time in seconds is "9" */
class AboutThread extends Thread {
private volatile Thread about;
AboutDialog ad;
AboutThread(AboutDialog ad) {
this.ad = ad;
public void stopped() {
about = null;
ad.dispose();
ad = null;
System.gc();
public synchronized void run() {
Thread thisThread = Thread.currentThread();
about = thisThread;
System.out.println("About thread is running!");
ad.start();
while (about == thisThread) {
try {
Thread.sleep(1000);
} catch (InterruptedException ex) {
     System.err.println("Thread.sleep error: " + ex);
String s = new String(getCurrentDateTime("s"));
if (s.equals("9")) {
ad.setVisible(false);
ad.setModal(false);
ad.setVisible(true);
System.out.println(9);
this.stop();
/* Shows a dialog describing the User Log application */
public class AboutDialog extends Dialog implements ActionListener {
public AboutDialog(Frame parent, String title) {
     super(parent, title, false);
     Panel labelPanel = new Panel();
     labelPanel.setLayout(new BorderLayout());
     labelPanel.setBackground(Color.gray);
JLabel jlab = new JLabel("User Log 1.0");
jlab.setHorizontalAlignment(SwingConstants.CENTER);
jlab.setFont(new Font("Monospaced", Font.BOLD, 28));
JLabel jlab1 = new JLabel("Copyright(c) 2001 Soft Wares. All Rights Reserved.");
jlab1.setHorizontalAlignment(SwingConstants.CENTER);
labelPanel.add(jlab, "Center");
     labelPanel.add(jlab1, "South");
     add(labelPanel, "Center");
     Panel buttonPanel = new Panel();
buttonPanel.setBackground(Color.gray);
     Button okButton = new Button("OK");
     okButton.addActionListener(this);
     buttonPanel.add(okButton);
     add(buttonPanel, "South");
     setSize(400, 130);
     setLocation(parent.getLocationOnScreen().x + 200,
          parent.getLocationOnScreen().y + 200);
public void start() {
show();
public void actionPerformed(ActionEvent e) {
     setVisible(false);
     dispose();
at.stopped();
}

Answer 1

ooops! i'm sorry. in the AboutDialog Class, it should be "super(parent, title, true)" for it to be modal.
anyway, it seemed that posting the partial code above of the whole app is not so understandable.
what i like to address here is that: how do i dispose or get rid of the thread-dispatched modal dialog by not making mouse clicks or any other user intervention? i wanted it to be disposed by the same thread, which dispatched it, when a certain variable value (global or local) is met. is this possible?