public BasicInternalFrameTitlePane(JInternalFrame f) 
{
       
        frame = f;
        installTitlePane();
}

 protected  void addSubComponents() 
{
        add(menuBar);
        add(iconButton);
        add(maxButton);
        add(closeButton);
}

 protected  void addSystemMenuItems(JMenu systemMenu) 
{
        JMenuItem mi = (JMenuItem)systemMenu.add(restoreAction);
        mi.setMnemonic('R");
        mi = (JMenuItem)systemMenu.add(moveAction);
        mi.setMnemonic('M");
        mi = (JMenuItem)systemMenu.add(sizeAction);
        mi.setMnemonic('S");
        mi = (JMenuItem)systemMenu.add(iconifyAction);
        mi.setMnemonic('n");
        mi = (JMenuItem)systemMenu.add(maximizeAction);
        mi.setMnemonic('x");
        systemMenu.add(new JSeparator());
        mi = (JMenuItem)systemMenu.add(closeAction);
        mi.setMnemonic('C");
}

 protected  void assembleSystemMenu() 
{
        menuBar = createSystemMenuBar();
        windowMenu = createSystemMenu();
        menuBar.add(windowMenu);
        addSystemMenuItems(windowMenu);
        enableActions();
}

 ActionMap createActionMap() 
{
        ActionMap map = new ActionMapUIResource();
        map.put("showSystemMenu", new ShowSystemMenuAction(true));
        map.put("hideSystemMenu", new ShowSystemMenuAction(false));
        return map;
}

 protected  void createActions() 
{
        maximizeAction = new MaximizeAction();
        iconifyAction = new IconifyAction();
        closeAction = new CloseAction();
        restoreAction = new RestoreAction();
        moveAction = new MoveAction();
        sizeAction = new SizeAction();
}

 protected  void createButtons() 
{
        iconButton = new NoFocusButton(
                     "InternalFrameTitlePane.iconifyButtonAccessibleName",
                     "InternalFrameTitlePane.iconifyButtonOpacity");
        iconButton.addActionListener(iconifyAction);
        if (iconButtonToolTip != null && iconButtonToolTip.length() != 0) {
            iconButton.setToolTipText(iconButtonToolTip);
        }
        maxButton = new NoFocusButton(
                        "InternalFrameTitlePane.maximizeButtonAccessibleName",
                        "InternalFrameTitlePane.maximizeButtonOpacity");
        maxButton.addActionListener(maximizeAction);
        closeButton = new NoFocusButton(
                      "InternalFrameTitlePane.closeButtonAccessibleName",
                      "InternalFrameTitlePane.closeButtonOpacity");
        closeButton.addActionListener(closeAction);
        if (closeButtonToolTip != null && closeButtonToolTip.length() != 0) {
            closeButton.setToolTipText(closeButtonToolTip);
        }
        setButtonIcons();
}

 protected LayoutManager createLayout() 
{
        return getHandler();
}

 protected PropertyChangeListener createPropertyChangeListener() 
{
        return getHandler();
}

 protected JMenu createSystemMenu() 
{
        return new JMenu("    ");
}

 protected JMenuBar createSystemMenuBar() 
{
        menuBar = new SystemMenuBar();
        menuBar.setBorderPainted(false);
        return menuBar;
}

 protected  void enableActions() 
{
        restoreAction.setEnabled(frame.isMaximum() || frame.isIcon());
        maximizeAction.setEnabled(
            (frame.isMaximizable() && !frame.isMaximum() && !frame.isIcon()) ||
            (frame.isMaximizable() && frame.isIcon()));
        iconifyAction.setEnabled(frame.isIconifiable() && !frame.isIcon());
        closeAction.setEnabled(frame.isClosable());
        sizeAction.setEnabled(false);
        moveAction.setEnabled(false);
}

 protected String getTitle(String text,
    FontMetrics fm,
    int availTextWidth) 
{
        return SwingUtilities2.clipStringIfNecessary(
                           frame, fm, text, availTextWidth);
}

 protected  void installDefaults() 
{
        maxIcon = UIManager.getIcon("InternalFrame.maximizeIcon");
        minIcon = UIManager.getIcon("InternalFrame.minimizeIcon");
        iconIcon = UIManager.getIcon("InternalFrame.iconifyIcon");
        closeIcon = UIManager.getIcon("InternalFrame.closeIcon");
        selectedTitleColor = UIManager.getColor("InternalFrame.activeTitleBackground");
        selectedTextColor = UIManager.getColor("InternalFrame.activeTitleForeground");
        notSelectedTitleColor = UIManager.getColor("InternalFrame.inactiveTitleBackground");
        notSelectedTextColor = UIManager.getColor("InternalFrame.inactiveTitleForeground");
        setFont(UIManager.getFont("InternalFrame.titleFont"));
        closeButtonToolTip =
                UIManager.getString("InternalFrame.closeButtonToolTip");
        iconButtonToolTip =
                UIManager.getString("InternalFrame.iconButtonToolTip");
        restoreButtonToolTip =
                UIManager.getString("InternalFrame.restoreButtonToolTip");
        maxButtonToolTip =
                UIManager.getString("InternalFrame.maxButtonToolTip");
}

 protected  void installListeners() 
{
        if( propertyChangeListener == null ) {
            propertyChangeListener = createPropertyChangeListener();
        }
        frame.addPropertyChangeListener(propertyChangeListener);
}

 protected  void installTitlePane() 
{
        installDefaults();
        installListeners();
        createActions();
        enableActions();
        createActionMap();
        setLayout(createLayout());
        assembleSystemMenu();
        createButtons();
        addSubComponents();
}

 public  void paintComponent(Graphics g) 
{
        paintTitleBackground(g);
        if(frame.getTitle() != null) {
            boolean isSelected = frame.isSelected();
            Font f = g.getFont();
            g.setFont(getFont());
            if(isSelected)
                g.setColor(selectedTextColor);
            else
                g.setColor(notSelectedTextColor);
            // Center text vertically.
            FontMetrics fm = SwingUtilities2.getFontMetrics(frame, g);
            int baseline = (getHeight() + fm.getAscent() - fm.getLeading() -
                    fm.getDescent()) / 2;
            int titleX;
            Rectangle r = new Rectangle(0, 0, 0, 0);
            if (frame.isIconifiable())  r = iconButton.getBounds();
            else if (frame.isMaximizable())  r = maxButton.getBounds();
            else if (frame.isClosable())  r = closeButton.getBounds();
            int titleW;
            String title = frame.getTitle();
            if( BasicGraphicsUtils.isLeftToRight(frame) ) {
              if (r.x == 0)  r.x = frame.getWidth()-frame.getInsets().right;
              titleX = menuBar.getX() + menuBar.getWidth() + 2;
              titleW = r.x - titleX - 3;
              title = getTitle(frame.getTitle(), fm, titleW);
            } else {
                titleX = menuBar.getX() - 2
                         - SwingUtilities2.stringWidth(frame,fm,title);
            }
            SwingUtilities2.drawString(frame, g, title, titleX, baseline);
            g.setFont(f);
        }
}

 protected  void paintTitleBackground(Graphics g) 
{
        boolean isSelected = frame.isSelected();
        if(isSelected)
            g.setColor(selectedTitleColor);
        else
            g.setColor(notSelectedTitleColor);
        g.fillRect(0, 0, getWidth(), getHeight());
}

Invoked from paintComponent. Paints the background of the titlepane. All text and icons will then be rendered on top of this background.

 protected  void postClosingEvent(JInternalFrame frame) 
{
        InternalFrameEvent e = new InternalFrameEvent(
            frame, InternalFrameEvent.INTERNAL_FRAME_CLOSING);
        // Try posting event, unless there's a SecurityManager.
        if (JInternalFrame.class.getClassLoader() == null) {
            try {
                Toolkit.getDefaultToolkit().getSystemEventQueue().postEvent(e);
                return;
            } catch (SecurityException se) {
                // Use dispatchEvent instead.
            }
        }
        frame.dispatchEvent(e);
}

Post a WINDOW_CLOSING-like event to the frame, so that it can be treated like a regular Frame.

 protected  void setButtonIcons() 
{
        if(frame.isIcon()) {
            if (minIcon != null) {
                iconButton.setIcon(minIcon);
            }
            if (restoreButtonToolTip != null &&
                    restoreButtonToolTip.length() != 0) {
                iconButton.setToolTipText(restoreButtonToolTip);
            }
            if (maxIcon != null) {
                maxButton.setIcon(maxIcon);
            }
            if (maxButtonToolTip != null && maxButtonToolTip.length() != 0) {
                maxButton.setToolTipText(maxButtonToolTip);
            }
        } else if (frame.isMaximum()) {
            if (iconIcon != null) {
                iconButton.setIcon(iconIcon);
            }
            if (iconButtonToolTip != null && iconButtonToolTip.length() != 0) {
                iconButton.setToolTipText(iconButtonToolTip);
            }
            if (minIcon != null) {
                maxButton.setIcon(minIcon);
            }
            if (restoreButtonToolTip != null &&
                    restoreButtonToolTip.length() != 0) {
                maxButton.setToolTipText(restoreButtonToolTip);
            }
        } else {
            if (iconIcon != null) {
                iconButton.setIcon(iconIcon);
            }
            if (iconButtonToolTip != null && iconButtonToolTip.length() != 0) {
                iconButton.setToolTipText(iconButtonToolTip);
            }
            if (maxIcon != null) {
                maxButton.setIcon(maxIcon);
            }
            if (maxButtonToolTip != null && maxButtonToolTip.length() != 0) {
                maxButton.setToolTipText(maxButtonToolTip);
            }
        }
        if (closeIcon != null) {
            closeButton.setIcon(closeIcon);
        }
}

 protected  void showSystemMenu() 
{
        //      windowMenu.setPopupMenuVisible(true);
      //      windowMenu.setVisible(true);
      windowMenu.doClick();
}

 protected  void uninstallDefaults() 
{

}

 protected  void uninstallListeners() 
{
        frame.removePropertyChangeListener(propertyChangeListener);
        handler = null;
}