JMenu and JTabbedPane conflict

Okay I know this should be very simple but my compiler, jGRASP, is not
making it so. The problem I have is that the compiler says the
following:

TabbedPaneDemo.java:131: cannot resolve symbol
symbol : method createMenuBar ()
location: class javax.swing.JComponent
          frame.setJMenuBar(newContentPane.createMenuBar());

Now to be honest I really don't see what its not getting so I thought I
would get a second opinion.

Below is the code for my program so far (Yes I'm moding a demo for my
own use):

import java.awt.*;
import java.awt.event.*;
import javax.swing.JTabbedPane;
import javax.swing.ImageIcon;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JFrame;
import javax.swing.JComponent;
import javax.swing.JMenu;
import javax.swing.JMenuItem;
import javax.swing.JMenuBar;
//Specific AWTs that your calling
//import java.awt.BorderLayout;
//import java.awt.Dimension;
//import java.awt.GridLayout;
//import java.awt.event.KeyEvent;

public class TabbedPaneDemo extends JPanel {

 public JMenuBar createMenuBar()
     {
        JMenuBar menuBar;
        JMenu menu, submenu;
        JMenuItem menuItem;

        //Create the menu bar.
        menuBar = new JMenuBar();

        //Build the first menu.
        menu = new JMenu("File");
        menuBar.add(menu);

        //a group of JMenuItems
        menuItem = new JMenuItem("Open");
        menu.add(menuItem);

        //a submenu
        menu.addSeparator();
        submenu = new JMenu("A submenu");

        menuItem = new JMenuItem("An item in the submenu");
        submenu.add(menuItem);

        menuItem = new JMenuItem("Another item");
        submenu.add(menuItem);
        menu.add(submenu);

        return menuBar;
    }

    public TabbedPaneDemo() {
        super(new GridLayout(1, 1));

        JTabbedPane tabbedPane = new JTabbedPane();
        ImageIcon icon = createImageIcon("middle.gif");

        JComponent panel1 = makeTextPanel("Panel #1");
        tabbedPane.addTab("Tab 1", icon, panel1,
                          "Does nothing");
        tabbedPane.setMnemonicAt(0, KeyEvent.VK_1);

        JComponent panel2 = makeTextPanel("Panel #2");
        tabbedPane.addTab("Tab 2", icon, panel2,
                          "Does twice as much nothing");
        tabbedPane.setMnemonicAt(1, KeyEvent.VK_2);

        JComponent panel3 = makeTextPanel("Panel #3");
        tabbedPane.addTab("Tab 3", icon, panel3,
                          "Still does nothing");
        tabbedPane.setMnemonicAt(2, KeyEvent.VK_3);

        JComponent panel4 = makeTextPanel(
                "Panel #4 (has a preferred size of 410 x 50).");
    panel4.setPreferredSize(new Dimension(410, 50));
        tabbedPane.addTab("Tab 4", icon, panel4,
                          "Does nothing at all");
        tabbedPane.setMnemonicAt(3, KeyEvent.VK_4);

        //Add the tabbed pane to this panel.
        add(tabbedPane);

        //Uncomment the following line to use scrolling tabs.
        //tabbedPane.setTabLayoutPolicy(JTabbedPane.SCROLL_TAB_LAYOUT);
    }

    protected JComponent makeTextPanel(String text)
     {
        JPanel panel = new JPanel(false);
        JLabel filler = new JLabel(text);
        filler.setHorizontalAlignment(JLabel.CENTER);
        panel.setLayout(new GridLayout(1, 1));
        panel.add(filler);
        return panel;
    }

    /** Returns an ImageIcon, or null if the path was invalid. */
    protected static ImageIcon createImageIcon(String path)
     {
        java.net.URL imgURL = TabbedPaneDemo.class.getResource(path);
        if (imgURL != null) {
            return new ImageIcon(imgURL);
        } else {
            System.err.println("Couldn't find file: " + path);
            return null;
        }
    }

    /**
     * Create the GUI and show it. For thread safety,
     * this method should be invoked from the
     * event-dispatching thread.
     */
    private static void createAndShowGUI() {
        //Create and set up the window.
        JFrame frame = new JFrame("TabbedPaneDemo");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        //Create and set up the content pane.
        JComponent newContentPane = new TabbedPaneDemo();
          frame.setJMenuBar(newContentPane.createMenuBar());
        newContentPane.setOpaque(true); //content panes must be opaque
        frame.getContentPane().add(new TabbedPaneDemo(),
                                 BorderLayout.CENTER);

        //Display the window.
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        //Schedule a job for the event-dispatching thread:
        //creating and showing this application's GUI.
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }
}