1 /*
   2  * Copyright (c) 2003, 2005, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package sun.awt;
  27 
  28 import java.awt.event.FocusEvent;
  29 import java.awt.Component;
  30 
  31 /**
  32  * This class represents FocusEvents with a known "cause" - reason why this event happened. It can
  33  * be mouse press, traversal, activation, and so on - all causes are described as Cause enum. The
  34  * event with the cause can be constructed in two ways - explicitly through constructor of
  35  * CausedFocusEvent class or implicitly, by calling appropriate requestFocusXXX method with "cause"
  36  * parameter. The default cause is UNKNOWN.
  37  */
  38 public class CausedFocusEvent extends FocusEvent {
  39     public enum Cause {
  40         UNKNOWN,
  41         MOUSE_EVENT,
  42         TRAVERSAL,
  43         TRAVERSAL_UP,
  44         TRAVERSAL_DOWN,
  45         TRAVERSAL_FORWARD,
  46         TRAVERSAL_BACKWARD,
  47         MANUAL_REQUEST,
  48         AUTOMATIC_TRAVERSE,
  49         ROLLBACK,
  50         NATIVE_SYSTEM,
  51         ACTIVATION,
  52         CLEAR_GLOBAL_FOCUS_OWNER,
  53         RETARGETED
  54     };
  55 
  56     private final Cause cause;
  57 
  58     public Cause getCause() {
  59         return cause;
  60     }
  61 
  62     public String toString() {
  63         return "java.awt.FocusEvent[" + super.paramString() + ",cause=" + cause + "] on " + getSource();
  64     }
  65 
  66     public CausedFocusEvent(Component source, int id, boolean temporary,
  67                             Component opposite, Cause cause) {
  68         super(source, id, temporary, opposite);
  69         if (cause == null) {
  70             cause = Cause.UNKNOWN;
  71         }
  72         this.cause = cause;
  73     }
  74 
  75     /**
  76      * Retargets the original focus event to the new target.  If the
  77      * original focus event is CausedFocusEvent, it remains such and
  78      * cause is copied.  Otherwise, new CausedFocusEvent is created,
  79      * with cause as RETARGETED.
  80      * @return retargeted event, or null if e is null
  81      */
  82     public static FocusEvent retarget(FocusEvent e, Component newSource) {
  83         if (e == null) return null;
  84 
  85         return new CausedFocusEvent(newSource, e.getID(), e.isTemporary(), e.getOppositeComponent(),
  86                                     (e instanceof CausedFocusEvent) ? ((CausedFocusEvent)e).getCause() : Cause.RETARGETED);
  87     }
  88 }