import java.awt.BorderLayout;
import javax.swing.JDesktopPane;
import javax.swing.JFrame;
import javax.swing.JInternalFrame;
import javax.swing.JTextArea;
public class Main {
public static void main(String[] argv) throws Exception {
boolean resizable = true;
boolean closeable = true;
boolean maximizable = true;
boolean iconifiable = true;
String title = "Frame Title";
JInternalFrame iframe = new JInternalFrame(title, resizable, closeable, maximizable,
iconifiable);
iframe.setSize(300, 300);
iframe.setVisible(true);
iframe.getContentPane().add(new JTextArea());
JDesktopPane desktop = new JDesktopPane();
desktop.add(iframe);
JFrame frame = new JFrame();
frame.getContentPane().add(desktop, BorderLayout.CENTER);
frame.setSize(300, 300);
frame.setVisible(true);
}
}