public class Test extends JFrame{    
    MyPanel mp=null;
    public Test(){
        mp=new MyPanel();
        this.add(mp);
        this.setSize(550, 400);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setVisible(true);
    }     
    public static void main(String[] args){
        new Test();
    }
} 
class MyPanel extends JPanel{     
    Image image=null;     
    public void paint(Graphics g){
        try {
            image=ImageIO.read(new File("H:\\aa.jpg"));//插入图片
            g.drawImage(image, 0, 0, 550, 400, null);
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}