001/* WindowEvent.java -- window change event
002   Copyright (C) 1999, 2002, 2005  Free Software Foundation, Inc.
003
004This file is part of GNU Classpath.
005
006GNU Classpath is free software; you can redistribute it and/or modify
007it under the terms of the GNU General Public License as published by
008the Free Software Foundation; either version 2, or (at your option)
009any later version.
010
011GNU Classpath is distributed in the hope that it will be useful, but
012WITHOUT ANY WARRANTY; without even the implied warranty of
013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014General Public License for more details.
015
016You should have received a copy of the GNU General Public License
017along with GNU Classpath; see the file COPYING.  If not, write to the
018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
01902110-1301 USA.
020
021Linking this library statically or dynamically with other modules is
022making a combined work based on this library.  Thus, the terms and
023conditions of the GNU General Public License cover the whole
024combination.
025
026As a special exception, the copyright holders of this library give you
027permission to link this library with independent modules to produce an
028executable, regardless of the license terms of these independent
029modules, and to copy and distribute the resulting executable under
030terms of your choice, provided that you also meet, for each linked
031independent module, the terms and conditions of the license of that
032module.  An independent module is a module which is not derived from
033or based on this library.  If you modify this library, you may extend
034this exception to your version of the library, but you are not
035obligated to do so.  If you do not wish to do so, delete this
036exception statement from your version. */
037
038
039package java.awt.event;
040
041import gnu.java.lang.CPStringBuilder;
042
043import java.awt.Frame;
044import java.awt.Window;
045
046/**
047 * This event is generated when there is a change in a window. This includes
048 * creation, closing, iconification, activation, and focus changes. There
049 * are three listeners, for three types of events: WindowListeners deal with
050 * the lifecycle of a window, WindowStateListeners deal with window state
051 * like maximization, and WindowFocusListeners deal with focus switching to
052 * or from a window.
053 *
054 * @author Aaron M. Renn (arenn@urbanophile.com)
055 * @see WindowAdapter
056 * @see WindowListener
057 * @see WindowFocusListener
058 * @see WindowStateListener
059 * @since 1.1
060 * @status updated to 1.4
061 */
062public class WindowEvent extends ComponentEvent
063{
064  /**
065   * Compatible with JDK 1.1+.
066   */
067  private static final long serialVersionUID = -1567959133147912127L;
068
069  /** This is the first id in the range of event ids used by this class. */
070  public static final int WINDOW_FIRST = 200;
071
072  /** This is the id for a window that is opened. */
073  public static final int WINDOW_OPENED = 200;
074
075  /** This is the id for a window that is about to close. */
076  public static final int WINDOW_CLOSING = 201;
077
078  /** This is the id for a window that finished closing. */
079  public static final int WINDOW_CLOSED = 202;
080
081  /** This is the id for a window that is iconified. */
082  public static final int WINDOW_ICONIFIED = 203;
083
084  /** This is the id for a window that is de-iconified. */
085  public static final int WINDOW_DEICONIFIED = 204;
086
087  /** This is the id for a window that is activated. */
088  public static final int WINDOW_ACTIVATED = 205;
089
090  /** This is the id for a window that is de-activated. */
091  public static final int WINDOW_DEACTIVATED = 206;
092
093  /**
094   * This is the id for a window becoming the focused window.
095   *
096   * @since 1.4
097   */
098  public static final int WINDOW_GAINED_FOCUS = 207;
099
100  /**
101   * This is the id for a window losing all focus.
102   *
103   * @since 1.4
104   */
105  public static final int WINDOW_LOST_FOCUS = 208;
106
107  /**
108   * This is the id for a window state change, such as maximization.
109   *
110   * @since 1.4
111   */
112  public static final int WINDOW_STATE_CHANGED = 209;
113
114  /** This is the last id in the range of event ids used by this class. */
115  public static final int WINDOW_LAST = 209;
116
117  /**
118   * The other Window involved in a focus or activation change. For
119   * WINDOW_ACTIVATED and WINDOW_GAINED_FOCUS events, this is the window that
120   * lost focus; for WINDOW_DEACTIVATED and WINDOW_LOST_FOCUS, this is the
121   * window that stole focus; and for other events (or when native
122   * implementation does not have the data available), this is null.
123   *
124   * @see #getOppositeWindow()
125   * @serial the opposite window, or null
126   * @since 1.4
127   */
128  private final Window opposite;
129
130  /**
131   * The former state of the window.
132   *
133   * @serial bitmask of the old window state
134   * @since 1.4
135   */
136  private final int oldState;
137
138  /**
139   * The present state of the window.
140   *
141   * @serial bitmask of the new window state
142   * @since 1.4
143   */
144  private final int newState;
145
146  /**
147   * Initializes a new instance of <code>WindowEvent</code> with the specified
148   * parameters. Note that an invalid id leads to unspecified results.
149   *
150   * @param source the window that generated this event
151   * @param id the event id
152   * @param opposite the window that received the opposite event, or null
153   * @param oldState the previous state of this window
154   * @param newState the new state of this window
155   * @throws IllegalArgumentException if source is null
156   * @since 1.4
157   */
158  public WindowEvent(Window source, int id, Window opposite,
159                     int oldState, int newState)
160  {
161    super(source, id);
162    this.opposite = opposite;
163    this.oldState = oldState;
164    this.newState = newState;
165  }
166
167  /**
168   * Initializes a new instance of <code>WindowEvent</code> with the specified
169   * parameters. Note that an invalid id leads to unspecified results.
170   *
171   * @param source the window that generated this event
172   * @param id the event id
173   * @param opposite the window that received the opposite event, or null
174   * @throws IllegalArgumentException if source is null
175   * @since 1.4
176   */
177  public WindowEvent(Window source, int id, Window opposite)
178  {
179    this(source, id, opposite, 0, 0);
180  }
181
182  /**
183   * Initializes a new instance of <code>WindowEvent</code> with the specified
184   * parameters. Note that an invalid id leads to unspecified results.
185   *
186   * @param source the window that generated this event
187   * @param id the event id
188   * @param oldState the previous state of this window
189   * @param newState the new state of this window
190   * @throws IllegalArgumentException if source is null
191   * @since 1.4
192   */
193  public WindowEvent(Window source, int id, int oldState, int newState)
194  {
195    this(source, id, null, oldState, newState);
196  }
197
198  /**
199   * Initializes a new instance of <code>WindowEvent</code> with the specified
200   * parameters. Note that an invalid id leads to unspecified results.
201   *
202   * @param source the window that generated this event
203   * @param id the event id
204   * @throws IllegalArgumentException if source is null
205   */
206  public WindowEvent(Window source, int id)
207  {
208    this(source, id, null, 0, 0);
209  }
210
211  /**
212   * Returns the event source as a <code>Window</code>. If the source has
213   * subsequently been modified to a non-Window, this returns null.
214  *
215  * @return the event source as a <code>Window</code>
216  */
217  public Window getWindow()
218  {
219    return source instanceof Window ? (Window) source : null;
220  }
221
222  /**
223   * Returns the opposite window if this window was involved in an activation
224   * or focus change. For WINDOW_ACTIVATED and WINDOW_GAINED_FOCUS events,
225   * this is the window that lost focus; for WINDOW_DEACTIVATED and
226   * WINDOW_LOST_FOCUS, this is the window that stole focus; and for other
227   * events (or when native implementation does not have the data available),
228   * this is null.
229   *
230   * @return the opposite window, or null
231   * @since 1.4
232   */
233  public Window getOppositeWindow()
234  {
235    return opposite;
236  }
237
238  /**
239   * Returns the state of this window before the event. This is the bitwise
240   * or of fields in Frame: NORMAL, ICONIFIED, MAXIMIZED_HORIZ, MAXIMIZED_VERT,
241   * and MAXIMIZED_BOTH.
242   *
243   * @return the former state
244   * @see Frame#getExtendedState()
245   * @since 1.4
246   */
247  public int getOldState()
248  {
249    return oldState;
250  }
251
252  /**
253   * Returns the state of this window after the event. This is the bitwise
254   * or of fields in Frame: NORMAL, ICONIFIED, MAXIMIZED_HORIZ, MAXIMIZED_VERT,
255   * and MAXIMIZED_BOTH.
256   *
257   * @return the updated state
258   * @see Frame#getExtendedState()
259   * @since 1.4
260   */
261  public int getNewState()
262  {
263    return newState;
264  }
265
266  /**
267   * Returns a string that identifies this event. This is formatted as the
268   * field name of the id, followed by the opposite window, old state, and
269   * new state.
270   *
271   * @return a string that identifies this event
272   */
273  public String paramString()
274  {
275    CPStringBuilder s = new CPStringBuilder();
276    switch (id)
277      {
278      case WINDOW_OPENED:
279        s.append("WINDOW_OPENED,opposite=");
280        break;
281      case WINDOW_CLOSING:
282        s.append("WINDOW_CLOSING,opposite=");
283        break;
284      case WINDOW_CLOSED:
285        s.append("WINDOW_CLOSED,opposite=");
286        break;
287      case WINDOW_ICONIFIED:
288        s.append("WINDOW_ICONIFIED,opposite=");
289        break;
290      case WINDOW_DEICONIFIED:
291        s.append("WINDOW_DEICONIFIED,opposite=");
292        break;
293      case WINDOW_ACTIVATED:
294        s.append("WINDOW_ACTIVATED,opposite=");
295        break;
296      case WINDOW_DEACTIVATED:
297        s.append("WINDOW_DEACTIVATED,opposite=");
298        break;
299      case WINDOW_GAINED_FOCUS:
300        s.append("WINDOW_GAINED_FOCUS,opposite=");
301        break;
302      case WINDOW_LOST_FOCUS:
303        s.append("WINDOW_LOST_FOCUS,opposite=");
304        break;
305      case WINDOW_STATE_CHANGED:
306        s.append("WINDOW_STATE_CHANGED,opposite=");
307        break;
308      default:
309        s.append("unknown type,opposite=");
310      }
311    return s.append(opposite).append(",oldState=").append(oldState)
312      .append(",newState=").append(newState).toString();
313  }
314} // class WindowEvent