JTabbedPane中添加了JPanel，然后在Jpanel中如何添加JInternalFrame

代码如下
public class TestInternalFrame {
private JFrame frame = new JFrame("JInternalFrame");
// private JTabbedPane tab = new JTabbedPane();
private JPanel mainPanel = (JPanel) frame.getContentPane();
private JDesktopPane desk = new JDesktopPane();
private JInternalFrame internalFrame = new JInternalFrame();
private JPanel internalPanel = new JPanel();
public TestInternalFrame()
{

    internalPanel.add(new JLabel(new ImageIcon("D:/java/mylove.jpg")));
    internalFrame.add(internalPanel);
    desk.add(internalFrame);
    mainPanel.add(desk,BorderLayout.CENTER);

    internalFrame.pack();
    internalFrame.setVisible(true);

// frame.add(tab);
// tab.addTab("图片", mainPanel);

    frame.setVisible(true);
    frame.setSize(500,500);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public static void main(String[] args)
{
    new TestInternalFrame();
}

}
运行效果如下：图片并没有显示出来：

看看你的“D:/java/mylove.jpg”引用的图片路径是否有问题，代码是对的。