java – 如何在jpanel中添加可视化内容？

public class Stone {

    private int x,y;
    private Color color;

    private static final int radius = 18;

    Stone(Color color) {
        this.color = color;
    }

    public Stone(int x,int y,Color color) {
        this(color);
        this.x = x;
        this.y = y;
    }

    void draw(Graphics g) {
        g.setColor(color);

        g.fillOval(x - radius,y - radius,2 * radius,2 * radius);
    }

    void setX(int x) {
        this.x = x;
    }

    void setY(int y) {
        this.y = y;
    }
}

我想在JPanel上绘制它们.我是否必须在JPanel的paint方法中执行此操作,或者是否可以使用JPanel的add方法？