title: Swing JOptionPane background color is different
body: <p>I have been trying to display a messagebox in Swing with <code>JOptionPane</code> by using: </p>
  
  <pre><code>JOptionPane.showMessageDialog(Component parentComponent,
                                       Object message,
                                       String title,
                                       int messageType)
                                throws HeadlessException
  </code></pre>
  
  <p>The message box looks as shown <a href="https://i.stack.imgur.com/ssbZn.png" rel="nofollow noreferrer">here</a>:</p>
  
  <p><img src="https://i.stack.imgur.com/ssbZn.png"></p>
  
  <p>When I add this line</p>
  
  <pre><code>UIManager.put("OptionPane.background", Color.white);
  </code></pre>
  
  <p>Option pane looks as shown <a href="https://i.stack.imgur.com/odwJU.png" rel="nofollow noreferrer">here</a>:</p>
  
  <p><img src="https://i.stack.imgur.com/odwJU.png"></p>
  
  <p>What should I do in order to get a pure white background in the message box?</p>