请问Canvas作为方法参数怎么画图呢?

public void doCanvas(Canvas _Canvas){
 
  这边怎样用 paint(Graphics g)
 
  }

public void paintComponent(Graphics g) 
{
  Graphics2D g2 = (Graphics2D)g;
  super.paintComponent(g);
  Image img = Toolkit.getDefaultToolkit().getImage("d:\\a.jpg");
  g2.drawImage(img, 0, 0, this.getWidth(), this.getHeight(), this);
}