/*
 * Gary Cornell and Cay S. Horstmann, Core Java (Book/CD-ROM)
 * Published By SunSoft Press/Prentice-Hall
 * Copyright (C) 1996 Sun Microsystems Inc.
 * All Rights Reserved. ISBN 0-13-565755-5
 *
 * Permission to use, copy, modify, and distribute this 
 * software and its documentation for NON-COMMERCIAL purposes
 * and without fee is hereby granted provided that this 
 * copyright notice appears in all copies. 
 * 
 * THE AUTHORS AND PUBLISHER MAKE NO REPRESENTATIONS OR 
 * WARRANTIES ABOUT THE SUITABILITY OF THE SOFTWARE, EITHER 
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE 
 * IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A 
 * PARTICULAR PURPOSE, OR NON-INFRINGEMENT. THE AUTHORS
 * AND PUBLISHER SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED 
 * BY LICENSEE AS A RESULT OF USING, MODIFYING OR DISTRIBUTING 
 * THIS SOFTWARE OR ITS DERIVATIVES.
 */
 
/**
 * @version 1.00 07 Feb 1996 
 * @author Cay Horstmann
 */

import java.awt.*;

public class Sketch extends Frame
{  public Sketch()
   {  setTitle("Sketch");
   }
   
   public boolean handleEvent(Event evt)
   {  if (evt.id == Event.WINDOW_DESTROY) System.exit(0);
      return super.handleEvent(evt);
   }
   
   public boolean keyDown(Event evt, int key)
   {  int d = ((evt.modifiers & Event.SHIFT_MASK) == 0) ?
      1 : 5;
      if (key == Event.LEFT) add(-d, 0);
      else if (key == Event.RIGHT) add(d, 0);
      else if (key == Event.UP) add(0, -d);
      else if (key == Event.DOWN) add(0, d);
      else return false;
      return true;
   }

   public void update(Graphics g) 
   {  paint(g); 
      requestFocus();
   } 

   public void paint(Graphics g) 
   {  g.drawLine(start.x, start.y, end.x, end.y);
      start.x = end.x;
      start.y = end.y;
   }

   public void add(int dx, int dy)
   {  end.x += dx;
      end.y += dy;
      repaint(); 
   }  
           
   public static void main(String[] args)
   {  Frame f = new Sketch();
      f.resize(300, 200);
      f.show();  
   }
   
   private Point start = new Point(0, 0);
   private Point end = new Point(0, 0); 

}