public class T extends JPanel {
private List drawItemList = new ArrayList();
protected void paintComponent(Graphics g) {
super.paintComponent(g);
for (int i = 0; i < drawItemList.size(); i++) {
DrawItem item = (DrawItem) drawItemList.get(i);
item.draw(g);
}
}
public static void main(String[] args) {
final T t = new T();
t.drawItemList.add(new Rect(100, 100, 100, 100, Color.RED));
t.drawItemList.add(new Circle(180, 180, 50, Color.BLUE));