import java.awt.BorderLayout;
import java.awt.Dimension;

import javax.swing.JFrame;
import javax.swing.JProgressBar;
import javax.swing.JWindow;
import javax.swing.SwingUtilities;

public class InditerminateProgressBar {

    public InditerminateProgressBar() {
        initFrame();
        createProgressBarWindow();
    }
    
    private void initFrame() {
        JFrame frame = new JFrame("Progress Bar");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(300, 300);
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    private void createProgressBarWindow() {
        JProgressBar pb = new JProgressBar();
        pb.setPreferredSize(new Dimension(200, pb.getPreferredSize().height - 4));
        pb.setIndeterminate(true);
        JWindow win = new JWindow();
        win.add(pb, BorderLayout.CENTER);
        win.setSize(pb.getPreferredSize());
        win.setAlwaysOnTop(true);
        win.setLocationRelativeTo(null);
        win.setVisible(true);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(() -> new InditerminateProgressBar());
    }
}