Swing UI Halts with Thread.sleep()

Your query suggests that utilizing Thread.sleep() in conjunction with JFileChooser leads to a UI suspension, inhibiting the display of Swing elements. The reason behind this behavior lies in the fact that Thread.sleep() is invoked on the Event Dispatch Thread (EDT), which is responsible for managing the GUI. Consequently, the UI enters a sleep state, rendering it unresponsive.

To address this issue, it is recommended to employ a javax.swing.Timer instead. Here's how it works:

Timer t = new Timer(1000 * 5, new ActionListener() {
    public void actionPerformed(ActionEvent e) {
        // Perform your recurring task
    }
});

By utilizing Timer, your periodic task is executed outside the EDT, ensuring that the UI remains responsive while your task runs in parallel.