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// Display some bouncing hoops.  Also added code to close the
// application when the user clicks the mouse in the close box.

// Written by Wayne Pollock, Tampa, FL USA, 1999

import java.awt.*;
import java.awt.event.*;

public class Hoops extends Frame
{
   int dir = 1;  // "1" for forward, "-1" for backward.
   int hoop1_pos = 10;
   int hoop2_pos = 290 - 40;  // inner frame width - hoop diameter

   public Hoops ()
   {
      setTitle( "Bouncing Hoops" );
      setSize( 300, 200 );
      setBackground( Color.cyan );
      setVisible( true );
   }

   public static void main ( String [] args )
   {
      Frame hoopsFrame = new Hoops();

      // Window closing code:
      hoopsFrame.addWindowListener(
         new WindowAdapter()
         {  public void windowClosing( WindowEvent e )
            {  System.exit( 0 );
            }
         }
      );

      for ( int i=0; i<5000; ++i )
      {
         hoopsFrame.repaint();
         try
         {  Thread.sleep( 30 );
         } catch ( InterruptedException ie ) {}
      }
      System.exit( 0 );
   }

   public void paint ( Graphics g )
   {
      if ( hoop1_pos >= (150-40-1) || hoop1_pos < 10 )
         dir = -dir;

      hoop1_pos += dir * 3;
      hoop2_pos -= dir * 3;

      g.setColor( Color.red );
      g.drawOval( hoop1_pos, 60, 40, 40 );
      g.setColor( Color.blue );
      g.drawOval( hoop2_pos, 60, 40, 40 );

      g.setColor( Color.black );
      g.setFont( new Font("SansSerif", Font.BOLD, 24) );
      g.drawString( "Bouncing Hoops!", 50, 170);
   }
}