title: JPanel not painting, JFrame remains blank
body: <p>I'm working on a digital Pokemon card-like game. When I try to paint any of my images, the JFrame remains empty. It may be a simple error, but I have not been able to find a solution. On Stack Overflow, I have seen many issues like mine though their solutions don't work on my code. Here's the code:
  The class for the JFrame:</p>
  
  <pre><code>import javax.swing.JFrame;
  
  
  public class Rocks extends JFrame{
  
  public Rocks(){
      setVisible(true);
      setTitle("Rocks Card Game");
      setSize(1200,297);
      add(new Display());
      setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  }
  public static void main(String[] args) {
      new Rocks();
  }
  
  }
  </code></pre>
  
  <p>The JPanel Class:</p>
  
  <pre><code>    import java.awt.Color;
  import java.awt.Graphics;
  import java.awt.Graphics2D;
  import java.awt.Image;
  
  import javax.swing.ImageIcon;
  import javax.swing.JPanel;
  
  
  public class Display extends JPanel{
      Image granite;
      public Display(){
          granite = new ImageIcon("C:\\Users\\Raj\\Pictures\\Granite.png").getImage();
          setBackground(Color.black);
      }
      public void paint(Graphics g){
          Graphics2D g2d = (Graphics2D) g;
          g2d.drawImage(granite,0,0,null);
      }
  }
  </code></pre>