//Create the edit menu.
    protected JMenu createEditMenu() {
        JMenu menu = new JMenu("Edit");

        //Undo and redo are actions of our own creation.
        undoAction = new UndoAction();
        menu.add(undoAction);

        redoAction = new RedoAction();
        menu.add(redoAction);

        menu.addSeparator();

        //These actions come from the default editor kit.
        //Get the ones we want and stick them in the menu.
        menu.add(getActionByName(DefaultEditorKit.cutAction));
        menu.add(getActionByName(DefaultEditorKit.copyAction));
        menu.add(getActionByName(DefaultEditorKit.pasteAction));

        menu.addSeparator();

        menu.add(getActionByName(DefaultEditorKit.selectAllAction));
        return menu;
    }

    //Create the style menu.
    protected JMenu createStyleMenu() {
        JMenu menu = new JMenu("Style");

        Action action = new StyledEditorKit.BoldAction();
        action.putValue(Action.NAME, "Bold");
        menu.add(action);

        action = new StyledEditorKit.ItalicAction();
        action.putValue(Action.NAME, "Italic");
        menu.add(action);

        action = new StyledEditorKit.UnderlineAction();
        action.putValue(Action.NAME, "Underline");
        menu.add(action);

        menu.addSeparator();

        menu.add(new StyledEditorKit.FontSizeAction("12", 12));
        menu.add(new StyledEditorKit.FontSizeAction("14", 14));
        menu.add(new StyledEditorKit.FontSizeAction("18", 18));

        menu.addSeparator();

        menu.add(new StyledEditorKit.FontFamilyAction("Serif",
                                                      "Serif"));
        menu.add(new StyledEditorKit.FontFamilyAction("SansSerif",
                                                      "SansSerif"));

        menu.addSeparator();

        menu.add(new StyledEditorKit.ForegroundAction("Red",
                                                      Color.red));
        menu.add(new StyledEditorKit.ForegroundAction("Green",
                                                      Color.green));
        menu.add(new StyledEditorKit.ForegroundAction("Blue",
                                                      Color.blue));
        menu.add(new StyledEditorKit.ForegroundAction("Black",
                                                      Color.black));

        return menu;
    }

    protected void initDocument() {
        String initString[] =
                { "Use the mouse to place the caret.",
                  "Use the edit menu to cut, copy, paste, and select text.",
                  "Also to undo and redo changes.",
                  "Use the style menu to change the style of the text.",
                  "Use the arrow keys on the keyboard or these emacs key bindings to move the caret:",
                  "Ctrl-f, Ctrl-b, Ctrl-n, Ctrl-p." };

        SimpleAttributeSet[] attrs = initAttributes(initString.length);

        try {
            for (int i = 0; i < initString.length; i ++) {
                doc.insertString(doc.getLength(), initString[i] + newline,
                        attrs[i]);
            }
        } catch (BadLocationException ble) {
            System.err.println("Couldn't insert initial text.");
        }
    }

    protected SimpleAttributeSet[] initAttributes(int length) {
        //Hard-code some attributes.
        SimpleAttributeSet[] attrs = new SimpleAttributeSet[length];

        attrs[0] = new SimpleAttributeSet();
        StyleConstants.setFontFamily(attrs[0], "SansSerif");
        StyleConstants.setFontSize(attrs[0], 16);

        attrs[1] = new SimpleAttributeSet(attrs[0]);
        StyleConstants.setBold(attrs[1], true);

        attrs[2] = new SimpleAttributeSet(attrs[0]);
        StyleConstants.setItalic(attrs[2], true);

        attrs[3] = new SimpleAttributeSet(attrs[0]);
        StyleConstants.setFontSize(attrs[3], 20);

        attrs[4] = new SimpleAttributeSet(attrs[0]);
        StyleConstants.setFontSize(attrs[4], 12);

        attrs[5] = new SimpleAttributeSet(attrs[0]);
        StyleConstants.setForeground(attrs[5], Color.red);

        return attrs;
    }

    //The following two methods allow us to find an
    //action provided by the editor kit by its name.
    private HashMap<Object, Action> createActionTable(JTextComponent textComponent) {
        HashMap<Object, Action> actions = new HashMap<Object, Action>();
        Action[] actionsArray = textComponent.getActions();
        for (int i = 0; i < actionsArray.length; i++) {
            Action a = actionsArray[i];
            actions.put(a.getValue(Action.NAME), a);
        }
	return actions;
    }

    private Action getActionByName(String name) {
        return actions.get(name);
    }

    class UndoAction extends AbstractAction {
        public UndoAction() {
            super("Undo");
            setEnabled(false);
        }

        public void actionPerformed(ActionEvent e) {
            try {
                undo.undo();
            } catch (CannotUndoException ex) {
                System.out.println("Unable to undo: " + ex);
                ex.printStackTrace();
            }
            updateUndoState();
            redoAction.updateRedoState();
        }

        protected void updateUndoState() {
            if (undo.canUndo()) {
                setEnabled(true);
                putValue(Action.NAME, undo.getUndoPresentationName());
            } else {
                setEnabled(false);
                putValue(Action.NAME, "Undo");
            }
        }
    }

    class RedoAction extends AbstractAction {
        public RedoAction() {
            super("Redo");
            setEnabled(false);
        }

        public void actionPerformed(ActionEvent e) {
            try {
                undo.redo();
            } catch (CannotRedoException ex) {
                System.out.println("Unable to redo: " + ex);
                ex.printStackTrace();
            }
            updateRedoState();
            undoAction.updateUndoState();
        }

        protected void updateRedoState() {
            if (undo.canRedo()) {
                setEnabled(true);
                putValue(Action.NAME, undo.getRedoPresentationName());
            } else {
                setEnabled(false);
                putValue(Action.NAME, "Redo");
            }
        }
    }

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

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

    //The standard main method.
    public static void main(String[] args) {
        //Schedule a job for the event dispatch thread:
        //creating and showing this application's GUI.
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                //Turn off metal's use of bold fonts
	        UIManager.put("swing.boldMetal", Boolean.FALSE);
		createAndShowGUI();
            }
        });
    }
}