Lecture 13 - slide 26 : 30

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

public class CanvasDraw {

  public static void main(String[] args){
     Frame myFrame = new Frame("Canvas Drawing");
     myFrame.setSize(100,200);
     Drawing myDrawing = new Drawing();
     myFrame.addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent e) {
             System.exit(0);
           }
       });
     myFrame.add("Center", myDrawing);
     myFrame.pack();
     myFrame.setVisible(true);
  }
}

class Drawing extends Canvas {
  private Dimension size = new Dimension(100,150);

  public void paint(Graphics g){
   g.drawLine(0,0,100,50);
   g.fillOval(50,50,25,30);
  }

  public Dimension getMinimumSize() {
       return size;
  }

  public Dimension getPreferredSize() {
      return getMinimumSize();
  }
}