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

public class CGTemplate extends JFrame
{

   public static final int CANVAS_WIDTH  = 640;
   public static final int CANVAS_HEIGHT = 480;


   private DrawCanvas canvas;

   public CGTemplate() {
      canvas = new DrawCanvas();
      canvas.setPreferredSize(new Dimension(CANVAS_WIDTH, CANVAS_HEIGHT));

      Container cp = getContentPane();
      cp.add(canvas);

      setDefaultCloseOperation(EXIT_ON_CLOSE);
      pack();
      setTitle("......");
      setVisible(true);
   }

   private class DrawCanvas extends JPanel {

      public void paintComponent(Graphics g) {
         super.paintComponent(g);
         setBackground(Color.BLACK);

         g.setColor(Color.YELLOW);
         g.drawLine(30, 40, 100, 200);
         g.drawOval(150, 180, 10, 10);
         g.drawRect(200, 210, 20, 30);
         g.setColor(Color.RED);
         g.fillOval(300, 310, 30, 50);
         g.fillRect(400, 350, 60, 50);

         g.setColor(Color.WHITE);
         g.setFont(new Font("Monospaced", Font.PLAIN, 12));
         g.drawString("Testing custom drawing ...", 10, 20);
      }
   }


   public static void main(String[] args) {

      SwingUtilities.invokeLater(new Runnable() {

         public void run() {
            new CGTemplate();
         }
      });
   }
}