I realise there have been several posting on this subject already.
However, despite these, I still can't quite work out how to do this.

I need to take the image from a file (.gif .jpg etc), ensure that the
entire image fits on a JPanel of some size, then put this JPanel onto
another Jpanel.

From what I could gather, it looked like I had to extend JPanel and
override paint().  The problem comes when I try to use drawImage().
Here's the code.

//relevent imports

public class Picture extends JPanel
{
  private String fileName;
 
  /** Creates a new instance of Picture */
 
public Picture(String file)
  {
     fileName=file;
  }
 
  public void paint(Graphics g)
  {
     super.paintComponent(g);
     
  }
}