我正在尝试制作一个简单的程序，该程序将通过随机生成的点绘制一条曲线，但是出了点问题，编译器给出了一个错误，我才刚刚开始学习Java，这是第一个任务。我希望你能指出我的错误。这是代码

public class Framey {

private static int fact(int n) {
    int fact = 1;
    for(int i = 1; i <= n;i++) {
        fact *= i;
    }
    return fact;
}

private static double bernstein(float t,int n,int i) {
    return (fact(n)/(fact(i)*fact(n-i)))*Math.pow(1-t,n-i)*Math.pow(t,i);
}


private JFrame frame;



/**
 * Launch the application.
 */
public static void main(String[] args) {
    EventQueue.invokeLater(new Runnable() {
        public void run() {
            try {
                Framey window = new Framey();
                window.frame.setVisible(true);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    });
}

/**
 * Create the application.
 */
public Framey() {
    initialize();

}

/**
 * Initialize the contents of the frame.
 */
private void initialize() {
    frame = new JFrame();
    frame.setbounds(100,100,450,300);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.getcontentPane().setLayout(null);

    JPanel panel = new JPanel();
    panel.setBackground(Color.LIGHT_GRAY);
    panel.setbounds(23,35,250,200);
    frame.getcontentPane().add(panel);


    JSpinner spinner = new JSpinner();
    spinner.setbounds(291,113,30,20);
    frame.getcontentPane().add(spinner);

    JLabel warning = new JLabel("Value cannot be larger than 8!");
    warning.setfont(new Font("Tahoma",Font.BOLD,9));
    warning.setbounds(283,144,141,53);
    frame.getcontentPane().add(warning);
    warning.setVisible(false);

    JButton btnNewButton = new JButton("New button");
    btnNewButton.addactionListener(new actionListener() {
        public void actionPerformed(actionEvent e) {
            int pointCount;

            pointCount = (int) spinner.getvalue();
            if (pointCount>8) {
                warning.setVisible(true);
            }else {warning.setVisible(false);}




            Point[] points = getPoints(pointCount); 

             drawScene(points);
        }
        private  Point[] getPoints(int pointCount) {
            Random val = new Random();
            Point[] points = new Point[pointCount];
            for(int i=0;i<pointCount;i++) {
                points[i].x = val.nextInt(panel.getWidth());
                points[i].y =val.nextInt(panel.getHeight());
            }
            return points;
        }
        private void drawScene(Point[] points) {
            int pWidth = panel.getWidth();
            int pHeight = panel.getHeight();
            Graphics g = panel.getGraphics();
            int pointCount = points.length;
            g.setColor(Color.WHITE);
            g.fillRect(0,pWidth,pHeight);

            if(pointCount>1) {
                float t = 0;
                while( t<=1) {
                    g.setColor(Color.DARK_GRAY);
                    besierCurve(t,points);
                    t+=0.001;
                }
            }
        };


        private void besierCurve(float t,Point[] points) {

            Graphics g = panel.getGraphics();
            int pointCount = points.length; 
            double bPoly[] = new double[pointCount];
            for(int i =0;i<pointCount;i++) {
                bPoly[i] = bernstein(t,pointCount-1,i+1);
            }

            double sumX = 0;
            double sumY = 0;
            for(int i=0;i<pointCount;i++) {
                sumX += bPoly[i] * points[i].x;
                sumY += bPoly[i] * points[i].y;
            }

            int x,y;
            x=(int) Math.round(sumX);
            y=(int) Math.round(sumY);
            g.drawLine(x,y,x,y);

        }






    });

bezjeLiikne.Framey $ 2.getPoints（Framey.java:106）处bezjeLiikne.Framey $ 2.actionPerformed（Framey.java:98）处的线程“ AWT-EventQueue-0”中的java.lang.NullPointerException