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

public class colorBox extends JFrame {

   public colorBox()
      {
      setSize( 500, 500 );
      setDefaultCloseOperation( EXIT_ON_CLOSE );
      setVisible(true);
      }

   public void paint(Graphics g)
      {
      g.setColor( Color.white ); // what does this do?
      g.fillRect( 0, 0, 500, 500 );

      g.setColor( Color.red );
      g.fillRect( 50, 50, 100, 75 );
      } 

   public static void main(String args [] )
      {
      colorBox app = new colorBox();
      }
  } // end class