/*
 *
 */

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

/**
 *
 */

public class CorrectAnimation {
    
  /**
   * entry point, create an instance and pass on to createAndShowGUI()
   */
  public static void main (String[] args) {
    final CorrectAnimation p = new CorrectAnimation();
    javax.swing.SwingUtilities.invokeLater(new Runnable() {
	  public void run() {
	    p.createAndShowGUI();
	  }
	});
    p.go();
  }


  
  public void go() {
    for(int i = 0; i < 400; i++) {
      synchronized(this) {
	try {
	  wait(10);
	} catch (InterruptedException e) {
	  System.err.println("waiting interrupted ???\n\n" + e);
	}
      }
      _y++;
      if (_frame != null) _frame.repaint();
    }
  }
  
  
  private JFrame _frame;

  /**
   * sets up everything, and then makes Frame visible
   */
  public void createAndShowGUI() {
      //Create and set up the window.
    _frame = new JFrame("CorrectAnimation") {
	  public void paint(Graphics g) {
	    g.setColor(Color.BLUE);
	    g.clearRect(0,0,400,400);
	    g.fillOval(_x-_radius,_y-_radius,2*_radius,2*_radius);
	    System.err.println("x " + _x + " y " + _y + " r " + _radius);
	  }
	};
    _frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    _frame.setPreferredSize(new Dimension(400,400));
    _frame.pack();
    _frame.setVisible(true);
  }
  
  private int _x = 200;
  private int _y = 0;
  private int _radius = 20;

}