How to change background color of JOptionPane?

For anyone having the same problem like above image, I found/adapted a solution. On my system, I got that result, whether I used the UIManager solution as others have posted, or made a JDialog and used jd.getContentPane().setBackground(Color.white). So here is the work-around I came up with, where you loop recursively through each component in the JOptionPane, and set each JPanel's background color:

private void getComponents(Container c){

    Component[] m = c.getComponents();

    for(int i = 0; i < m.length; i++){

        if(m[i].getClass().getName() == "javax.swing.JPanel")
            m[i].setBackground(Color.white);

        if(c.getClass().isInstance(m[i]))
            getComponents((Container)m[i]);
    }
}

In your code where you want to have the message pop-up, something along the lines of:

pane = new JOptionPane("Your message here", 
                JOptionPane.PLAIN_MESSAGE ,JOptionPane.DEFAULT_OPTION);
        getComponents(pane);
        pane.setBackground(Color.white);
        jd = pane.createDialog(this, "Message");
        jd.setVisible(true);

Where JOptionPane pane and JDialog jd have previously been created. Hope this helps anyone who had that issue.

Use this code if you have the same problem as erik k atwood. This solves the problem:

UIManager.put("OptionPane.background", Color.WHITE);
UIManager.getLookAndFeelDefaults().put("Panel.background", Color.WHITE);

By using the UIManager class

 import javax.swing.UIManager;

 UIManager UI=new UIManager();
 UI.put("OptionPane.background",new ColorUIResource(255,0,0));
 UI.put("Panel.background",new ColorUIResource(255,0,0));

or

 UIManager UI=new UIManager();
 UI.put("OptionPane.background", Color.white);
 UI.put("Panel.background", Color.white);

 JOptionPane.showMessageDialog(null,"Text","SetColor",JOptionPane.INFORMATION_MESSAGE);

Use something like this to change the background color just for this one message display and not the whole system...

    Object paneBG = UIManager.get("OptionPane.background");
    Object panelBG = UIManager.get("Panel.background");
    UIManager.put("OptionPane.background", new Color(...));
    UIManager.put("Panel.background", new Color(...));

    int ret = messageBox(msg, null, (short)type);

    UIManager.put("OptionPane.background", paneBG);
    UIManager.put("Panel.background", panelBG);