Animation in java....using java swings and images

This is not about animation.

You need to repaint the Field the snake is running on. repainting it every time you change something. Repainting it every time you add an apple or stone(? - where those in there?).

You can pass arguments to your Component that specify the snake and the obsticales:

public class PanelPlayGround extends JPanel{

 private Snake oSnake;
 private Obesticales oObsticales;

 public PanelPlayGround(final Snake oSnake, final Obsticales oObsticales){
   super():
   setSnake(oSnake);
   setObsticales(oObsticales);
   ignition();
 }

 private void ignition(){
   // let the fun begin
 }

 public void renewPanel(final Snake oNewSnake, final Obsticales oNewObsticales){
   setSnake(oNewSnake);
   setObsticales(oNewObsticales);
   this.dolayout(); // to repaint the Jpanel
 }

}

The Object Snake contains basically a list of x/y-values to specify which fields of the grid are occupied by the snake.
The Object Obsticales contains a List of Obstical.
Obstical contains one x/y value and one Enum ObsticalType.