Almost done with program, just a little help please

Question

I am almost done with a program but I just need to have the planet which is _ball be painted on the screen.  I am making a planet that orbits a sun, it all works but the planet is not painted on the screen, but I used a fill method.  Can you guys help?
public class MovingBall extends SmartEllipse
    int X0 = 100, Y0 = 100;
    double X2, Y2;
    double r = 10;
    double a = 0;
    double da = .04;
    double ecc = 1;
    double TWOPI = 2 * Math.PI;
    private javax.swing.JPanel _panel;
    public MovingBall (java.awt.Color aColor, javax.swing.JPanel aPanel)
     super(aColor);
     _panel = aPanel;
     X2 = X0 + r * Math.cos(a);
     Y2 = Y0 + r * Math.sin(a);
     this.setLocation(X2, Y2);
    public void move()
     a = a + da;
     a = a % TWOPI;
     X2 = X0 + r * ecc * Math.sin(a);
     Y2 = Y0 + r * ecc * Math.sin(a);
     this.setLocation (X2, Y2);
    public boolean inFront()
     return (a <= Math.PI);
    public void SetCircle(int x, int y)
     X0 = x;
     Y0 = y;
     //ecc = 1.0 - (double)pct/100;
    public void setAngleIncrement(double inc)
        da = inc;
    public void setCenter(double g, double s)
public class MovingBallPanel extends javax.swing.JPanel implements Mover, Controller
    private final int INIT_X = 250;
    private final int INIT_Y = 200;
    private SmartEllipse _sun;
    private Sky _sky;
    private final int SUN_DIAMETER = 60;
    private MovingBall _ball;
    private final int PLANET_DIAMETER = 35;
    private final int ORBIT_DIAMETER = 185;
    int _da = 1;
    int _ecc = 1;
    private final int INTERVAL = 100;
    private MoveTimer _timer;
    public MovingBallPanel()
     super();
     this.setBackground(java.awt.Color.BLACK);
     _sun = new SmartEllipse(java.awt.Color.YELLOW);
     _sun.setSize(SUN_DIAMETER, SUN_DIAMETER);
     _sun.setLocation(INIT_X - SUN_DIAMETER/2, INIT_Y - SUN_DIAMETER/2);
     _sky = new Sky();
     _ball = new MovingBall(java.awt.Color.RED, this);
     _ball.setCenter((INIT_X - PLANET_DIAMETER)/2, (INIT_Y - PLANET_DIAMETER)/2);
     _ball.setAngleIncrement(_da);     
     _timer = new MoveTimer(INTERVAL, this);
     _timer.start();
    public void move()
        _ball.move();
        this.repaint();
    public void go (boolean g)
     if (g) _ball.setAngleIncrement(_da);
        else _ball.setAngleIncrement(0);
    public void setSpeed(int degrees)
     _da = 2 * degrees;
     _ball.setAngleIncrement(_da);
    public void setEccentricity(int pct)
     _ecc = pct;
     //_ball.setEccentricity(_ecc);
    public void paintComponent(java.awt.Graphics aBrush)
     super.paintComponent (aBrush);
     java.awt.Graphics2D betterBrush = (java.awt.Graphics2D) aBrush;
     _sky.paintSky(betterBrush);
     _sun.draw(betterBrush);
     _sun.fill(betterBrush);
     _ball.draw(betterBrush);
     _ball.fill(betterBrush);
public class PlanetApp extends javax.swing.JFrame
    ControlPanel _controlPanel;
    MovingBallPanel _movingBallPanel;
    public PlanetApp (String title)
     super(title);
     this.setSize(600,500);
     this.setBackground(java.awt.Color.BLACK);
     this.setDefaultCloseOperation(javax.swing.JFrame.EXIT_ON_CLOSE);
     _movingBallPanel = new MovingBallPanel();
     _controlPanel = new ControlPanel(_movingBallPanel);
     this.add(_movingBallPanel, java.awt.BorderLayout.CENTER);
     this.add(_controlPanel, java.awt.BorderLayout.SOUTH);
     this.setVisible(true);
    public static void main (String [] args)
     PlanetApp app =  new PlanetApp("Lab 5");
public class SmartEllipse extends java.awt.geom.Ellipse2D.Double {
    private java.awt.Color _borderColor, _fillColor;  // attributes
    private int _rotation;
    private final int STROKE_WIDTH = 2;
    public SmartEllipse(java.awt.Color aColor){
     _borderColor = aColor;
     _fillColor = aColor;    // solid color to start
     _rotation = 0;         // no rotation for now
    // methods not provided by Java
    public void setBorderColor (java.awt.Color aColor) {
     _borderColor = aColor;
    public void setFillColor (java.awt.Color aColor) {
     _fillColor = aColor;
    public void setRotation (int aRotation) {
     _rotation = aRotation;
    // more readable versions of methods provided by Java
    public void setLocation (double x, double y) {
     this.setFrame (x, y, this.getWidth(),
                 this.getHeight());
    public void setSize (int aWidth, int aHeight) {
     this.setFrame(this.getX(), this.getY(),
                aWidth, aHeight);
    public void move (int aChangeInX, int aChangeInY) {
     this.setFrame((int)this.getX()+aChangeInX,
                (int)this.getY()+aChangeInY,
                this.getWidth(),
                this.getHeight());
    public void fill (java.awt.Graphics2D aBetterBrush){
     java.awt.Color savedColor = aBetterBrush.getColor();
     aBetterBrush.setColor(_fillColor);
     aBetterBrush.fill(this); // paint a solid ellipse
     aBetterBrush.setColor(savedColor);
    public void draw (java.awt.Graphics2D aBrush) {
     java.awt.Color savedColor = aBrush.getColor();
     aBrush.setColor(_borderColor);
     java.awt.Stroke savedStroke = aBrush.getStroke();
     aBrush.setStroke(new java.awt.BasicStroke(STROKE_WIDTH));
     aBrush.draw(this);
     aBrush.setStroke(savedStroke);
     aBrush.setColor(savedColor);
}

Answer 1

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