42

package test_21;

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

class MyCanvas extends Canvas {
private Image img;
private Graphics og;

public void init(){
Dimension d = getSize();
img = createImage(d.width,d.height);
og = img.getGraphics();
og.setColor(Color.blue);
og.fillRect(30,30,60,60);
og.setColor(Color.yellow);
og.fillOval(15,15,30,30);
og.setXORMode(Color.red);
og.fillOval(75,75,30,30);
og.setPaintMode();
og.setColor(Color.green);
og.fillArc(150,40,60,60,30,160);
}
public void paint(Graphics g){
if (img != null)
{ g.drawImage(img,20,20,this);}
}
}
public class DoubleBufferDemo
{
public static void main(String arg[])
{
Frame f = new Frame("DoubleBufferDemo");
f.setBounds(100,100,250,200);
MyCanvas mc = new MyCanvas();
f.add(mc);
f.setVisible(true);
mc.init();
mc.repaint();
f.addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e)
{System.exit(0);}
});
}
};