How do I add multiple JInternalFrames to 1 main JFrame

Question

It may seem like a silly question but I'd really appreciate any help offered. Sample code might be of assistance.
Thanks people :-)

Answer 1

It's very simple. Create a JFrame,
then create separate classes for each JInternalFrame (here: TFrame, SFrame, GFrame)
Here's some code:
public class GWorkBench extends JFrame {
public GWorkBench() {
//Set up the GUI.
desktop = new JDesktopPane(); //a specialized layered pane
setContentPane(desktop);
setJMenuBar(createMenuBar());
protected JMenuBar createMenuBar() {
JMenuBar menuBar = new JMenuBar();
JMenu menu = new JMenu("Modules");
menu.setMnemonic(KeyEvent.VK_D);
JMenuItem menuItem1 = new JMenuItem("Data Entry");
JMenuItem menuItem2 = new JMenuItem("Search Module");
JMenuItem menuItem3 = new JMenuItem("Generation Module");
menuItem1.setMnemonic(KeyEvent.VK_E);
menuItem2.setMnemonic(KeyEvent.VK_S);
menuItem3.setMnemonic(KeyEvent.VK_G);
menuItem1.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
createTFrame();
menuItem2.addActionListener(new ActionListener() {
     public void actionPerformed(ActionEvent e) {
          createSFrame();
menuItem2.addActionListener(new ActionListener() {
     public void actionPerformed(ActionEvent e) {
          createGFrame();
menu.add(menuItem1);
menu.add(menuItem2);
menu.add(menuItem3);
menuBar.add(menu);
return menuBar;