Swing - last JMenuItem occupy the rest of space on JMenuBar

Question

I find that if I have a JMenuBar, and the last element of it (the rightmost one) is a JMenuItem, it will occupy all the rest blank space on the JMenuBar, which is definitely not what we want.

Imagine an "About" JMenuItem as the rightmost item on a JMenuBar. It should only occupy the same space as the other menus.

See my SSCCE: (click the menu and hover over the menuitem on the right to see the effect)

import java.awt.Dimension;

import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.SwingUtilities;

public class JMenuItemLastOnMenuBar {

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                createGUI();
            }
        });
    }

    private static void createGUI() {
        JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        frame.setBounds(0, 0, 300, 300);

        JMenuBar bar = new JMenuBar();
        JMenu menu = new JMenu("Menu 1");
        JMenuItem item1 = new JMenuItem("Item 1");
        menu.add(item1);
        bar.add(menu);

        JMenuItem item2 = new JMenuItem("Item 2") {
            @Override
            public Dimension getPreferredSize() {
                return new Dimension(120, 25);
            }
        };
        bar.add(item2);

        frame.setJMenuBar(bar);

        frame.pack();
        frame.setVisible(true);
    }

}

Answer 1

You should override the method getMaximumSize

import java.awt.Dimension;

import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.SwingUtilities;

public class JMenuItemLastOnMenuBar {

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                createGUI();
            }
        });
    }

    private static void createGUI() {
        JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        frame.setBounds(0, 0, 300, 300);

        JMenuBar bar = new JMenuBar();
        JMenu menu = new JMenu("Menu 1");
        JMenuItem item1 = new JMenuItem("Item 1");
        menu.add(item1);
        bar.add(menu);

        JMenuItem item2 = new JMenuItem("Item 2") {
            @Override
            public Dimension getMaximumSize() {
                Dimension d1 = super.getPreferredSize();
                Dimension d2 = super.getMaximumSize();
                d2.width = d1.width;
                return d2;
            }
        };
        bar.add(item2);

        frame.setJMenuBar(bar);

        frame.pack();
        frame.setVisible(true);
    }

}