AWT(Mouse Paint Using Frame)

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

public class MousePaint extends Frame implements MouseMotionListener
{
private int x1, y1, x2, y2;
public MousePaint()
{
addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent we)
{
dispose();
System.exit(0);
}
});
addMouseMotionListener(this);
setBounds(50,50,400,250);
setVisible(true);
}
public static void main(String[] argv)
{
new MousePaint();
}
public void update(Graphics g)
{
paint(g);
}
public void paint(Graphics g)
{
g.setColor(Color.black);
g.drawLine(x1, y1, x2, y2);
}
public void mouseDragged(MouseEvent me)
{
me.consume();
int x = me.getX();
int y = me.getY();
if ( x1 == 0 )
{
x1 = x;
}
if ( y1 == 0 )
{
y1 = y;
}
x2 = x;
y2 = y;
repaint();
x1 = x2;
y1 = y2;
}
public void mouseMoved(MouseEvent me)
{ }
}