One of the Keyborad Event

import java.awt.*;
import javax.swing.*;
import java.util.*;
import java.awt.geom.*;
import java.awt.event.*;

public class Sketch{
public static void main(String args[]){

SketchFrame frame = new SketchFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.show();
}
}
/**
A frame with a panel for sketching a figure
*/

class SketchFrame extends JFrame{

public SketchFrame(){

setTitle("Sketch");
setSize(DEFAULT_WIDTH,DEFAULT_HEIGHT);
SketchPanel panel = new SketchPanel();
Container contentPane = getContentPane();
contentPane.add(panel);
}

public static int DEFAULT_WIDTH = 300;
public static int DEFAULT_HEIGHT =200;
}
/**
A panel for sketching with the keyboard.
*/

class SketchPanel extends JPanel{

public SketchPanel(){

last =new Point2D.Double(100,100);
lines = new ArrayList();
KeyHandler listener = new KeyHandler();
addKeyListener(listener);
setFocusable(true);
}
/**
Add a new line segment to the sketch.
@param dx the movement in x direction
@param dy the movement in x direction
*/
public void add(int dx,int dy){

//computer new end point
Point2D end = new Point2D.Double(last.getX()+dx,last.getY()+dy);

//add line segment
Line2D line = new Line2D.Double(last,end);
lines.add(line);
repaint();

//remember new end point
last = end;
}

public void paintComponent(Graphics g){

super.paintComponent(g);
Graphics2D g2 = (Graphics2D)g;

Rectangle2D rect = new Rectangle2D.Double(100,100,200,150);
//g2.setColor(Color.red);
g2.draw(rect);

// draw all lines
for(int i = 0; i < lines.size(); i++)
g2.draw((Line2D)lines.get(i));

}
private Point2D last;
private ArrayList lines;

private static final int SMALL_INCREMENT = 1;
private static final int LARGE_INCREMENT = 5;

private class KeyHandler implements KeyListener{

public void keyPressed(KeyEvent event){

int keyCode = event.getKeyCode();
// set distance
int d;
if(event.isShiftDown())
d = LARGE_INCREMENT;
else
d = SMALL_INCREMENT;

// add line segment
if(keyCode == KeyEvent.VK_LEFT) add(-d,0);
else if(keyCode == KeyEvent.VK_RIGHT) add(d,0);
else if(keyCode == KeyEvent.VK_UP) add(0,-d);
else if(keyCode == KeyEvent.VK_DOWN) add(0,d);

}

public void keyReleased(KeyEvent event){}

public void keyTyped(KeyEvent event){

char keyChar = event.getKeyChar();
// set distance
int d;
if(Character.isUpperCase(keyChar)){

d = LARGE_INCREMENT;
keyChar = Character.toLowerCase(keyChar);

}
else
d = SMALL_INCREMENT;

// add line segment
if(keyChar == 'h') add(-d,0);
else if(keyChar == 'l') add(d,0);
else if(keyChar == 'k') add(0,-d);
else if(keyChar == 'j') add(0,d);

}
}
}