MultipleFrames.java

import javax.swing.*;

public class MultipleFrames {
	JDesktopPane desk;
	JInternalFrame frame1, frame2, frame3, frame4;
	JFrame frame;

	public static void main(String[] args) {
		MultipleFrames d = new MultipleFrames();
	}

	public MultipleFrames() {
		frame = new JFrame("Multiple Frames");
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		desk = new JDesktopPane();
		frame1 = new JInternalFrame("Frame1", true, true, true, true);
		frame1.setBounds(20, 200, 150, 100);
		frame1.setVisible(true);
		frame2 = new JInternalFrame("Frame2", true, true, true, true);
		frame2.setBounds(20, 140, 150, 100);
		frame2.setVisible(true);
		frame3 = new JInternalFrame("Frame3", true, true, true, true);
		frame3.setBounds(20, 80, 150, 100);
		frame3.setVisible(true);
		frame4 = new JInternalFrame("Frame4", true, true, true, true);
		frame4.setBounds(20, 20, 150, 100);
		frame4.setVisible(true);
		desk.add(frame1);
		desk.add(frame2);
		desk.add(frame3);
		desk.add(frame4);
		frame.add(desk);
		frame.setSize(400, 400);
		frame.setVisible(true);
	}
}