How to have a menu accelerator with plus or minus signs in Swing?

I have tried setting the accelerator of a JMenuItem using the following :

item.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_PLUS, Toolkit.getDefaultToolkit().getMenuShortcutKeyMask()));

The menu item shows the shortcut ⌘+ (on a mac) but hitting these two keys won't trigger it. I have the same problem with the minus sign -.

I开发者_StackOverflows there any way to have a menu item with any of these signs as a shortcut ?

EDIT - Here is a SSCCE :

public class MenuWithPlus {
    public static void main(String[] args) {
        JFrame frame = new JFrame();

        JMenuBar bar = new JMenuBar();
        JMenu menu = new JMenu("View");
        JMenuItem item = new JMenuItem("Zoom in");
        item.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_PLUS, Toolkit.getDefaultToolkit().getMenuShortcutKeyMask()));
        item.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                System.out.println("ZOOM IN TRIGGERED");
            }
        });
        menu.add(item);
        bar.add(menu);
        frame.setJMenuBar(bar);

        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }
}

At accelerator code you have to modify to:

item.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_ADD, Event.CTRL_MASK));

A test that I made was add a key event listener on frame and catch de key value for plus (in this case ADD).

frame.addKeyListener(new KeyAdapter() {
    @Override
    public void keyPressed(KeyEvent e) {
        System.out.println(e.getKeyCode());
    }
    });

Are you using the +/- keys on the main keyboard vs. the numpad? They're seen as separate keys, so make sure you're using them consistently.

I think VK_PLUS is not used for the usual plus key (Shift-= on a US keyboard), but rather either the numpad +, or the + key on some German keyboards. Assuming you have a US keyboard, you might want Shift together with VK_EQUALS.

See this old bug and this discussion.