import java.util.*;
import java.io.*;
import java.applet.Applet;
import java.awt.*;
import java.awt.event.*;

public class pendel extends Applet implements Runnable, ActionListener{

    Button valja=new Button("  Lõpp  ");

    public pendel(){
      setLayout(new BorderLayout());
   	add(valja, BorderLayout.SOUTH);      
      valja.addActionListener(this);
      new Thread(this).start();
    }

    int nr=2;
    double nurk=0;
    double raadius=100;
    double samm=0.05;
    boolean veel=true;

  public void run(){
    while(veel){
      joonista();
    }
  }

  public void update(Graphics g){paint(g);}

  public void joonista(){
    Graphics g=this.getGraphics();
    if(g!=null){
      int keskx=getSize().width/2;
      int kesky=getSize().height/2;
      g.setColor(Color.blue);
      g.drawLine(keskx, kesky-100, (keskx+10)+(int)(raadius*Math.sin(nurk))-5, (kesky+10)+(int)(raadius*Math.cos(nurk))-5);
      g.fillOval(keskx+(int)(raadius*Math.sin(nurk))-5, kesky+(int)(raadius*Math.cos(nurk))-5, 20, 20);
      try{Thread.sleep(30);}catch(Exception e){}
      g.setColor(Color.white);
      g.drawLine(keskx, kesky-100, (keskx+10)+(int)(raadius*Math.sin(nurk))-5, (kesky+10)+(int)(raadius*Math.cos(nurk))-5);
      g.fillOval(keskx+(int)(raadius*Math.sin(nurk))-5, kesky+(int)(raadius*Math.cos(nurk))-5, 20, 20);
      if((nurk>Math.PI/nr) && (samm>0)){samm=-samm;nr=nr+1;}
      if((nurk<-Math.PI/nr) && (samm<0)){samm=-samm;nr=nr+1;}
      nurk=nurk+samm;
    }
  }
  
   public void actionPerformed(ActionEvent e){
     if(e.getSource()==valja){
       System.exit(0);
     }
   }

   public static void main(String agumendid[]){
     Frame f=new Frame();
     f.add(new pendel());
     f.setBackground(Color.white);
     f.setSize(300, 300);
     f.setVisible(true);
     f.addWindowListener(
       new WindowAdapter(){
         public void windowClosing(WindowEvent e){
           System.exit(0);
         }
       }
     );       
  }
}