import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
 
class Lab_06 extends JFrame{
    public Lab_06(String name) {
        super(name);
        Container contentPane = getContentPane();
        contentPane.setLayout(new BorderLayout());
        getContentPane().add(new Circle(300, 300));
        
        RandomBall display = new RandomBall(300, 300);
        display.setBackground(Color.yellow);
        contentPane.add(display, BorderLayout.CENTER);
        
        JPanel control = new JPanel(new FlowLayout());
        control.setBackground(Color.orange);
        contentPane.add(control, BorderLayout.SOUTH);
 
        JButton button = new JButton("Move");
        control.add(button);
        button.addActionListener(display);
        
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        pack();
        setResizable(false);
        setVisible(true );
    }
 
    public static void main(String[] args) {
        JFrame f = new Lab_06("Random Ball Generator");
    }
}
 
class Circle extends JLabel{
    public Circle(int width, int height) {
        setPreferredSize(new Dimension(width, height));
    }
} 
 
class RandomBall extends JLabel implements ActionListener{
    private int x0, y0, wBall, hBall, distance, wLabel, hLabel;
 
    public RandomBall(int width, int height) {
        setPreferredSize(new Dimension(width, height));
        setOpaque(true);
    }
 
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        g.setColor(Color.blue);
        g.fillOval(x0, y0, wBall, hBall);
        int x = getWidth(), y = getHeight();
        g.setColor(Color.RED);
        g.drawOval(x/300, y/300, x, y);
    }
 
    public void actionPerformed(ActionEvent e) {
        /* diameter of large circle is 300, radius 150 */
        /* diameter of ball is 80, radius 40 */
        /* So the center of the ball can move any where in a circle of radius 110. */
        /* and the angle theta can be anywhere between 0 and 2 pi radians. */
        double randomRadius = (110*Math.random()); 
        double theta = Math.PI*2d*Math.random(); 
        x0 = 150 + (int)(randomRadius  * Math.cos(theta));
        y0 = 150 + (int)(randomRadius  * Math.sin(theta));
        wBall = 40;
        hBall = 40;
        repaint();
    }
} 
{/java]