1. /*

  2.  * @(#)HeadlessException.java	1.8 04/03/29

  3.  *

  4.  * Copyright 2004 Sun Microsystems, Inc. All rights reserved.

  5.  * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.

  6.  */

  7. 

  8. package java.awt;

  9. 

  10. /**

  11.  * Thrown when code that is dependent on a keyboard, display, or mouse

  12.  * is called in an environment that does not support a keyboard, display,

  13.  * or mouse.

  14.  *

  15.  * @since 1.4

  16.  * @author  Michael Martak

  17.  */

  18. public class HeadlessException extends UnsupportedOperationException {

  19.     /*

  20.      * JDK 1.4 serialVersionUID

  21.      */

  22.     private static final long serialVersionUID = 167183644944358563L;

  23.     public HeadlessException() {}

  24.     public HeadlessException(String msg) {

  25.         super(msg);

  26.     }

  27.     public String getMessage() {

  28.         String superMessage = super.getMessage();

  29.         String headlessMessage = GraphicsEnvironment.getHeadlessMessage();

  30.         

  31.         if (superMessage == null) {

  32.             return headlessMessage;

  33.         } else if (headlessMessage == null) {

  34.             return superMessage;

  35.         } else {

  36.             return superMessage + headlessMessage;

  37.         }

  38.     }

  39. }