CanvasFiguresTest AWT Example

import java.awt.*;
import java.awt.event.*;
class CanvasFiguresTest extends Frame
implements ActionListener
{
Button b1=new Button("Line");
Button b2=new Button("Rect");
Button b3=new Button("Circle");
Button b4=new Button("Elpse");
Panel p=new Panel();
MyCanvas mc=new MyCanvas();

CanvasFiguresTest()
{
setSize(300,300);
setTitle("Different figures on canvas");
p.add(b1);
p.add(b2);
p.add(b3);
p.add(b4);
add(mc);
mc.setBackground(Color.red);
b1.addActionListener(this);
b2.addActionListener(this);
b3.addActionListener(this);
b4.addActionListener(this);
add(p,"South");
setVisible(true);
}
public void actionPerformed(ActionEvent e)
{
String s=e.getActionCommand();
if(s.equals("Line"))
mc.call(1);
if(s.equals("Rect"))
mc.call(2);
if(s.equals("Circle"))
mc.call(3);
if(s.equals("Elpse"))
mc.call(4);
}
public static void main(String[] args)
{
new CanvasFiguresTest();
}
}// end of frame class
class MyCanvas extends Canvas
{
int shape;
public void paint(Graphics g)
{
g.setColor(new Color(0,0,255));
if(shape==1)
g.drawLine(40,40,160,160);
if(shape==2)
g.drawRect(40,40,100,160);
if(shape==3)
g.drawOval(40,40,160,160);
if(shape==4)
g.drawOval(40,40,100,160);
}
public void call(int i)
{
shape=i;
repaint();
}

}