import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class Liikumine2 extends JPanel implements ActionListener{
   double x=100, y=50, r=5, dy=1, ddy=0.1;
   Timer t=new Timer(100, this);
   public Liikumine2(){
     t.start();
   }
   public void paintComponent(Graphics g){
     super.paintComponent(g);
     g.drawOval((int)(x-r), (int)(y-r), (int)(2*r), (int)(2*r));
   }
   public void actionPerformed(ActionEvent e){
     y+=dy;
	 dy+=ddy;
	 repaint();
   }
   public static void main(String[] arg){
     JFrame f=new JFrame();
	 f.getContentPane().add(new Liikumine2());
	 f.setSize(400, 300);
	 f.setVisible(true);
	 f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   }
}