FULL PRODUCT VERSION :
Java(TM) SE Runtime Environment (build 1.8.0_60-b27)
Java HotSpot(TM) 64-Bit Server VM (build 25.60-b23, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Windows 7

A DESCRIPTION OF THE PROBLEM :
When using a glue component to right align a toolbar component, the component does not appear. The issue occurs only with Synth based look and feels (i.e. Nimbus) and when a preferred size is set.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Execute the posted test case - the third toolbar button does not appear.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The button with the label B:3 should appear at the right edge of the toolbar.
ACTUAL -
Button B:3 does not appear

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
public class RightButtonTest extends JFrame
{
    public static void main(String[] args) throws Exception
    {
        UIManager.setLookAndFeel("com.sun.java.swing.plaf.nimbus.NimbusLookAndFeel");
        SwingUtilities.invokeLater(new Runnable()
        {
            public void run()
            {
                new RightButtonTest();
            }
        });
    }
    
    public RightButtonTest()
    {
        JToolBar bar = new JToolBar();
        bar.add(createButton(1));
        bar.add(createButton(2));
        bar.add(Box.createHorizontalGlue());
        bar.add(createButton(3));
        add(bar, BorderLayout.NORTH);

        setDefaultCloseOperation(EXIT_ON_CLOSE);
        setSize(600, 400);
        setVisible(true);
    }
    
    private static JButton createButton(int id)
    {
        JButton b = new JButton("B: " + id);
        b.setPreferredSize(new Dimension(60, b.getPreferredSize().height));
        return b;
    }
}
---------- END SOURCE ----------