1 /*
2 * Copyright (c) 2000, 2016, 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 package java.awt;
26
27 import java.awt.event.FocusEvent;
28 import java.awt.event.KeyEvent;
29 import java.awt.event.WindowEvent;
30 import java.awt.peer.ComponentPeer;
31 import java.awt.peer.LightweightPeer;
32 import java.lang.ref.WeakReference;
33 import java.util.LinkedList;
34 import java.util.Iterator;
35 import java.util.ListIterator;
36 import java.util.Set;
37
38 import sun.util.logging.PlatformLogger;
39
40 import sun.awt.AppContext;
41 import sun.awt.SunToolkit;
42 import sun.awt.AWTAccessor;
43 import sun.awt.TimedWindowEvent;
44
45 /**
46 * The default KeyboardFocusManager for AWT applications. Focus traversal is
47 * done in response to a Component's focus traversal keys, and using a
48 * Container's FocusTraversalPolicy.
49 * <p>
50 * Please see
51 * <a href="http://docs.oracle.com/javase/tutorial/uiswing/misc/focus.html">
52 * How to Use the Focus Subsystem</a>,
53 * a section in <em>The Java Tutorial</em>, and the
54 * <a href="../../java/awt/doc-files/FocusSpec.html">Focus Specification</a>
55 * for more information.
56 *
57 * @author David Mendenhall
58 *
59 * @see FocusTraversalPolicy
60 * @see Component#setFocusTraversalKeys
61 * @see Component#getFocusTraversalKeys
62 * @since 1.4
63 */
64 public class DefaultKeyboardFocusManager extends KeyboardFocusManager {
65 private static final PlatformLogger focusLog = PlatformLogger.getLogger("java.awt.focus.DefaultKeyboardFocusManager");
66
67 // null weak references to not create too many objects
68 private static final WeakReference<Window> NULL_WINDOW_WR =
69 new WeakReference<Window>(null);
70 private static final WeakReference<Component> NULL_COMPONENT_WR =
71 new WeakReference<Component>(null);
72 private WeakReference<Window> realOppositeWindowWR = NULL_WINDOW_WR;
73 private WeakReference<Component> realOppositeComponentWR = NULL_COMPONENT_WR;
74 private int inSendMessage;
75 private LinkedList<KeyEvent> enqueuedKeyEvents = new LinkedList<KeyEvent>();
76 private LinkedList<TypeAheadMarker> typeAheadMarkers = new LinkedList<TypeAheadMarker>();
77 private boolean consumeNextKeyTyped;
78 private Component restoreFocusTo;
79
80 static {
81 AWTAccessor.setDefaultKeyboardFocusManagerAccessor(
82 new AWTAccessor.DefaultKeyboardFocusManagerAccessor() {
83 public void consumeNextKeyTyped(DefaultKeyboardFocusManager dkfm, KeyEvent e) {
84 dkfm.consumeNextKeyTyped(e);
85 }
86 });
87 }
88
89 private static class TypeAheadMarker {
90 long after;
91 Component untilFocused;
92
93 TypeAheadMarker(long after, Component untilFocused) {
94 this.after = after;
95 this.untilFocused = untilFocused;
96 }
97 /**
98 * Returns string representation of the marker
99 */
100 public String toString() {
101 return ">>> Marker after " + after + " on " + untilFocused;
102 }
103 }
104
105 private Window getOwningFrameDialog(Window window) {
106 while (window != null && !(window instanceof Frame ||
107 window instanceof Dialog)) {
108 window = (Window)window.getParent();
109 }
110 return window;
111 }
112
113 /*
114 * This series of restoreFocus methods is used for recovering from a
115 * rejected focus or activation change. Rejections typically occur when
116 * the user attempts to focus a non-focusable Component or Window.
117 */
118 private void restoreFocus(FocusEvent fe, Window newFocusedWindow) {
119 Component realOppositeComponent = this.realOppositeComponentWR.get();
120 Component vetoedComponent = fe.getComponent();
121
122 if (newFocusedWindow != null && restoreFocus(newFocusedWindow,
123 vetoedComponent, false))
124 {
125 } else if (realOppositeComponent != null &&
126 doRestoreFocus(realOppositeComponent, vetoedComponent, false)) {
127 } else if (fe.getOppositeComponent() != null &&
128 doRestoreFocus(fe.getOppositeComponent(), vetoedComponent, false)) {
129 } else {
130 clearGlobalFocusOwnerPriv();
131 }
132 }
133 private void restoreFocus(WindowEvent we) {
134 Window realOppositeWindow = this.realOppositeWindowWR.get();
135 if (realOppositeWindow != null
136 && restoreFocus(realOppositeWindow, null, false))
137 {
138 // do nothing, everything is done in restoreFocus()
139 } else if (we.getOppositeWindow() != null &&
140 restoreFocus(we.getOppositeWindow(), null, false))
141 {
142 // do nothing, everything is done in restoreFocus()
143 } else {
144 clearGlobalFocusOwnerPriv();
145 }
146 }
147 private boolean restoreFocus(Window aWindow, Component vetoedComponent,
148 boolean clearOnFailure) {
149 restoreFocusTo = null;
150 Component toFocus =
151 KeyboardFocusManager.getMostRecentFocusOwner(aWindow);
152
153 if (toFocus != null && toFocus != vetoedComponent) {
154 if (getHeavyweight(aWindow) != getNativeFocusOwner()) {
155 // cannot restore focus synchronously
156 if (!toFocus.isShowing() || !toFocus.canBeFocusOwner()) {
157 toFocus = toFocus.getNextFocusCandidate();
158 }
159 if (toFocus != null && toFocus != vetoedComponent) {
160 if (!toFocus.requestFocus(false,
161 FocusEvent.Cause.ROLLBACK)) {
162 restoreFocusTo = toFocus;
163 }
164 return true;
165 }
166 } else if (doRestoreFocus(toFocus, vetoedComponent, false)) {
167 return true;
168 }
169 }
170 if (clearOnFailure) {
171 clearGlobalFocusOwnerPriv();
172 return true;
173 } else {
174 return false;
175 }
176 }
177 private boolean restoreFocus(Component toFocus, boolean clearOnFailure) {
178 return doRestoreFocus(toFocus, null, clearOnFailure);
179 }
180 private boolean doRestoreFocus(Component toFocus, Component vetoedComponent,
181 boolean clearOnFailure)
182 {
183 if (toFocus != vetoedComponent && toFocus.isShowing() && toFocus.canBeFocusOwner() &&
184 toFocus.requestFocus(false, FocusEvent.Cause.ROLLBACK))
185 {
186 return true;
187 } else {
188 Component nextFocus = toFocus.getNextFocusCandidate();
189 if (nextFocus != null && nextFocus != vetoedComponent &&
190 nextFocus.requestFocusInWindow(FocusEvent.Cause.ROLLBACK))
191 {
192 return true;
193 } else if (clearOnFailure) {
194 clearGlobalFocusOwnerPriv();
195 return true;
196 } else {
197 return false;
198 }
199 }
200 }
201
202 /**
203 * A special type of SentEvent which updates a counter in the target
204 * KeyboardFocusManager if it is an instance of
205 * DefaultKeyboardFocusManager.
206 */
207 private static class DefaultKeyboardFocusManagerSentEvent
208 extends SentEvent
209 {
210 /*
211 * serialVersionUID
212 */
213 private static final long serialVersionUID = -2924743257508701758L;
214
215 public DefaultKeyboardFocusManagerSentEvent(AWTEvent nested,
216 AppContext toNotify) {
217 super(nested, toNotify);
218 }
219 public final void dispatch() {
220 KeyboardFocusManager manager =
221 KeyboardFocusManager.getCurrentKeyboardFocusManager();
222 DefaultKeyboardFocusManager defaultManager =
223 (manager instanceof DefaultKeyboardFocusManager)
224 ? (DefaultKeyboardFocusManager)manager
225 : null;
226
227 if (defaultManager != null) {
228 synchronized (defaultManager) {
229 defaultManager.inSendMessage++;
230 }
231 }
232
233 super.dispatch();
234
235 if (defaultManager != null) {
236 synchronized (defaultManager) {
237 defaultManager.inSendMessage--;
238 }
239 }
240 }
241 }
242
243 /**
244 * Sends a synthetic AWTEvent to a Component. If the Component is in
245 * the current AppContext, then the event is immediately dispatched.
246 * If the Component is in a different AppContext, then the event is
247 * posted to the other AppContext's EventQueue, and this method blocks
248 * until the event is handled or target AppContext is disposed.
249 * Returns true if successfully dispatched event, false if failed
250 * to dispatch.
251 */
252 static boolean sendMessage(Component target, AWTEvent e) {
253 e.isPosted = true;
254 AppContext myAppContext = AppContext.getAppContext();
255 final AppContext targetAppContext = target.appContext;
256 final SentEvent se =
257 new DefaultKeyboardFocusManagerSentEvent(e, myAppContext);
258
259 if (myAppContext == targetAppContext) {
260 se.dispatch();
261 } else {
262 if (targetAppContext.isDisposed()) {
263 return false;
264 }
265 SunToolkit.postEvent(targetAppContext, se);
266 if (EventQueue.isDispatchThread()) {
267 EventDispatchThread edt = (EventDispatchThread)
268 Thread.currentThread();
269 edt.pumpEvents(SentEvent.ID, new Conditional() {
270 public boolean evaluate() {
271 return !se.dispatched && !targetAppContext.isDisposed();
272 }
273 });
274 } else {
275 synchronized (se) {
276 while (!se.dispatched && !targetAppContext.isDisposed()) {
277 try {
278 se.wait(1000);
279 } catch (InterruptedException ie) {
280 break;
281 }
282 }
283 }
284 }
285 }
286 return se.dispatched;
287 }
288
289 /*
290 * Checks if the focus window event follows key events waiting in the type-ahead
291 * queue (if any). This may happen when a user types ahead in the window, the client
292 * listeners hang EDT for a while, and the user switches b/w toplevels. In that
293 * case the focus window events may be dispatched before the type-ahead events
294 * get handled. This may lead to wrong focus behavior and in order to avoid it,
295 * the focus window events are reposted to the end of the event queue. See 6981400.
296 */
297 private boolean repostIfFollowsKeyEvents(WindowEvent e) {
298 if (!(e instanceof TimedWindowEvent)) {
299 return false;
300 }
301 TimedWindowEvent we = (TimedWindowEvent)e;
302 long time = we.getWhen();
303 synchronized (this) {
304 KeyEvent ke = enqueuedKeyEvents.isEmpty() ? null : enqueuedKeyEvents.getFirst();
305 if (ke != null && time >= ke.getWhen()) {
306 TypeAheadMarker marker = typeAheadMarkers.isEmpty() ? null : typeAheadMarkers.getFirst();
307 if (marker != null) {
308 Window toplevel = marker.untilFocused.getContainingWindow();
309 // Check that the component awaiting focus belongs to
310 // the current focused window. See 8015454.
311 if (toplevel != null && toplevel.isFocused()) {
312 SunToolkit.postEvent(AppContext.getAppContext(), new SequencedEvent(e));
313 return true;
314 }
315 }
316 }
317 }
318 return false;
319 }
320
321 /**
322 * This method is called by the AWT event dispatcher requesting that the
323 * current KeyboardFocusManager dispatch the specified event on its behalf.
324 * DefaultKeyboardFocusManagers dispatch all FocusEvents, all WindowEvents
325 * related to focus, and all KeyEvents. These events are dispatched based
326 * on the KeyboardFocusManager's notion of the focus owner and the focused
327 * and active Windows, sometimes overriding the source of the specified
328 * AWTEvent. If this method returns {@code false}, then the AWT event
329 * dispatcher will attempt to dispatch the event itself.
330 *
331 * @param e the AWTEvent to be dispatched
332 * @return {@code true} if this method dispatched the event;
333 * {@code false} otherwise
334 */
335 public boolean dispatchEvent(AWTEvent e) {
336 if (focusLog.isLoggable(PlatformLogger.Level.FINE) && (e instanceof WindowEvent || e instanceof FocusEvent)) {
337 focusLog.fine("" + e);
338 }
339 switch (e.getID()) {
340 case WindowEvent.WINDOW_GAINED_FOCUS: {
341 if (repostIfFollowsKeyEvents((WindowEvent)e)) {
342 break;
343 }
344
345 WindowEvent we = (WindowEvent)e;
346 Window oldFocusedWindow = getGlobalFocusedWindow();
347 Window newFocusedWindow = we.getWindow();
348 if (newFocusedWindow == oldFocusedWindow) {
349 break;
350 }
351
352 if (!(newFocusedWindow.isFocusableWindow()
353 && newFocusedWindow.isVisible()
354 && newFocusedWindow.isDisplayable()))
355 {
356 // we can not accept focus on such window, so reject it.
357 restoreFocus(we);
358 break;
359 }
360 // If there exists a current focused window, then notify it
361 // that it has lost focus.
362 if (oldFocusedWindow != null) {
363 boolean isEventDispatched =
364 sendMessage(oldFocusedWindow,
365 new WindowEvent(oldFocusedWindow,
366 WindowEvent.WINDOW_LOST_FOCUS,
367 newFocusedWindow));
368 // Failed to dispatch, clear by ourselves
369 if (!isEventDispatched) {
370 setGlobalFocusOwner(null);
371 setGlobalFocusedWindow(null);
372 }
373 }
374
375 // Because the native libraries do not post WINDOW_ACTIVATED
376 // events, we need to synthesize one if the active Window
377 // changed.
378 Window newActiveWindow =
379 getOwningFrameDialog(newFocusedWindow);
380 Window currentActiveWindow = getGlobalActiveWindow();
381 if (newActiveWindow != currentActiveWindow) {
382 sendMessage(newActiveWindow,
383 new WindowEvent(newActiveWindow,
384 WindowEvent.WINDOW_ACTIVATED,
385 currentActiveWindow));
386 if (newActiveWindow != getGlobalActiveWindow()) {
387 // Activation change was rejected. Unlikely, but
388 // possible.
389 restoreFocus(we);
390 break;
391 }
392 }
393
394 setGlobalFocusedWindow(newFocusedWindow);
395
396 if (newFocusedWindow != getGlobalFocusedWindow()) {
397 // Focus change was rejected. Will happen if
398 // newFocusedWindow is not a focusable Window.
399 restoreFocus(we);
400 break;
401 }
402
403 // Restore focus to the Component which last held it. We do
404 // this here so that client code can override our choice in
405 // a WINDOW_GAINED_FOCUS handler.
406 //
407 // Make sure that the focus change request doesn't change the
408 // focused Window in case we are no longer the focused Window
409 // when the request is handled.
410 if (inSendMessage == 0) {
411 // Identify which Component should initially gain focus
412 // in the Window.
413 //
414 // * If we're in SendMessage, then this is a synthetic
415 // WINDOW_GAINED_FOCUS message which was generated by a
416 // the FOCUS_GAINED handler. Allow the Component to
417 // which the FOCUS_GAINED message was targeted to
418 // receive the focus.
419 // * Otherwise, look up the correct Component here.
420 // We don't use Window.getMostRecentFocusOwner because
421 // window is focused now and 'null' will be returned
422
423
424 // Calculating of most recent focus owner and focus
425 // request should be synchronized on KeyboardFocusManager.class
426 // to prevent from thread race when user will request
427 // focus between calculation and our request.
428 // But if focus transfer is synchronous, this synchronization
429 // may cause deadlock, thus we don't synchronize this block.
430 Component toFocus = KeyboardFocusManager.
431 getMostRecentFocusOwner(newFocusedWindow);
432 boolean isFocusRestore = restoreFocusTo != null &&
433 toFocus == restoreFocusTo;
434 if ((toFocus == null) &&
435 newFocusedWindow.isFocusableWindow())
436 {
437 toFocus = newFocusedWindow.getFocusTraversalPolicy().
438 getInitialComponent(newFocusedWindow);
439 }
440 Component tempLost = null;
441 synchronized(KeyboardFocusManager.class) {
442 tempLost = newFocusedWindow.setTemporaryLostComponent(null);
443 }
444
445 // The component which last has the focus when this window was focused
446 // should receive focus first
447 if (focusLog.isLoggable(PlatformLogger.Level.FINER)) {
448 focusLog.finer("tempLost {0}, toFocus {1}",
449 tempLost, toFocus);
450 }
451 if (tempLost != null) {
452 tempLost.requestFocusInWindow(isFocusRestore ?
453 FocusEvent.Cause.ROLLBACK :
454 FocusEvent.Cause.ACTIVATION);
455 }
456
457 if (toFocus != null && toFocus != tempLost) {
458 // If there is a component which requested focus when this window
459 // was inactive it expects to receive focus after activation.
460 toFocus.requestFocusInWindow(FocusEvent.Cause.ACTIVATION);
461 }
462 }
463 restoreFocusTo = null;
464
465 Window realOppositeWindow = this.realOppositeWindowWR.get();
466 if (realOppositeWindow != we.getOppositeWindow()) {
467 we = new WindowEvent(newFocusedWindow,
468 WindowEvent.WINDOW_GAINED_FOCUS,
469 realOppositeWindow);
470 }
471 return typeAheadAssertions(newFocusedWindow, we);
472 }
473
474 case WindowEvent.WINDOW_ACTIVATED: {
475 WindowEvent we = (WindowEvent)e;
476 Window oldActiveWindow = getGlobalActiveWindow();
477 Window newActiveWindow = we.getWindow();
478 if (oldActiveWindow == newActiveWindow) {
479 break;
480 }
481
482 // If there exists a current active window, then notify it that
483 // it has lost activation.
484 if (oldActiveWindow != null) {
485 boolean isEventDispatched =
486 sendMessage(oldActiveWindow,
487 new WindowEvent(oldActiveWindow,
488 WindowEvent.WINDOW_DEACTIVATED,
489 newActiveWindow));
490 // Failed to dispatch, clear by ourselves
491 if (!isEventDispatched) {
492 setGlobalActiveWindow(null);
493 }
494 if (getGlobalActiveWindow() != null) {
495 // Activation change was rejected. Unlikely, but
496 // possible.
497 break;
498 }
499 }
500
501 setGlobalActiveWindow(newActiveWindow);
502
503 if (newActiveWindow != getGlobalActiveWindow()) {
504 // Activation change was rejected. Unlikely, but
505 // possible.
506 break;
507 }
508
509 return typeAheadAssertions(newActiveWindow, we);
510 }
511
512 case FocusEvent.FOCUS_GAINED: {
513 restoreFocusTo = null;
514 FocusEvent fe = (FocusEvent)e;
515 Component oldFocusOwner = getGlobalFocusOwner();
516 Component newFocusOwner = fe.getComponent();
517 if (oldFocusOwner == newFocusOwner) {
518 if (focusLog.isLoggable(PlatformLogger.Level.FINE)) {
519 focusLog.fine("Skipping {0} because focus owner is the same", e);
520 }
521 // We can't just drop the event - there could be
522 // type-ahead markers associated with it.
523 dequeueKeyEvents(-1, newFocusOwner);
524 break;
525 }
526
527 // If there exists a current focus owner, then notify it that
528 // it has lost focus.
529 if (oldFocusOwner != null) {
530 boolean isEventDispatched =
531 sendMessage(oldFocusOwner,
532 new FocusEvent(oldFocusOwner,
533 FocusEvent.FOCUS_LOST,
534 fe.isTemporary(),
535 newFocusOwner, fe.getCause()));
536 // Failed to dispatch, clear by ourselves
537 if (!isEventDispatched) {
538 setGlobalFocusOwner(null);
539 if (!fe.isTemporary()) {
540 setGlobalPermanentFocusOwner(null);
541 }
542 }
543 }
544
545 // Because the native windowing system has a different notion
546 // of the current focus and activation states, it is possible
547 // that a Component outside of the focused Window receives a
548 // FOCUS_GAINED event. We synthesize a WINDOW_GAINED_FOCUS
549 // event in that case.
550 final Window newFocusedWindow = SunToolkit.getContainingWindow(newFocusOwner);
551 final Window currentFocusedWindow = getGlobalFocusedWindow();
552 if (newFocusedWindow != null &&
553 newFocusedWindow != currentFocusedWindow)
554 {
555 sendMessage(newFocusedWindow,
556 new WindowEvent(newFocusedWindow,
557 WindowEvent.WINDOW_GAINED_FOCUS,
558 currentFocusedWindow));
559 if (newFocusedWindow != getGlobalFocusedWindow()) {
560 // Focus change was rejected. Will happen if
561 // newFocusedWindow is not a focusable Window.
562
563 // Need to recover type-ahead, but don't bother
564 // restoring focus. That was done by the
565 // WINDOW_GAINED_FOCUS handler
566 dequeueKeyEvents(-1, newFocusOwner);
567 break;
568 }
569 }
570
571 if (!(newFocusOwner.isFocusable() && newFocusOwner.isShowing() &&
572 // Refuse focus on a disabled component if the focus event
573 // isn't of UNKNOWN reason (i.e. not a result of a direct request
574 // but traversal, activation or system generated).
575 (newFocusOwner.isEnabled() || fe.getCause().equals(FocusEvent.Cause.UNKNOWN))))
576 {
577 // we should not accept focus on such component, so reject it.
578 dequeueKeyEvents(-1, newFocusOwner);
579 if (KeyboardFocusManager.isAutoFocusTransferEnabled()) {
580 // If FOCUS_GAINED is for a disposed component (however
581 // it shouldn't happen) its toplevel parent is null. In this
582 // case we have to try to restore focus in the current focused
583 // window (for the details: 6607170).
584 if (newFocusedWindow == null) {
585 restoreFocus(fe, currentFocusedWindow);
586 } else {
587 restoreFocus(fe, newFocusedWindow);
588 }
589 setMostRecentFocusOwner(newFocusedWindow, null); // see: 8013773
590 }
591 break;
592 }
593
594 setGlobalFocusOwner(newFocusOwner);
595
596 if (newFocusOwner != getGlobalFocusOwner()) {
597 // Focus change was rejected. Will happen if
598 // newFocusOwner is not focus traversable.
599 dequeueKeyEvents(-1, newFocusOwner);
600 if (KeyboardFocusManager.isAutoFocusTransferEnabled()) {
601 restoreFocus(fe, newFocusedWindow);
602 }
603 break;
604 }
605
606 if (!fe.isTemporary()) {
607 setGlobalPermanentFocusOwner(newFocusOwner);
608
609 if (newFocusOwner != getGlobalPermanentFocusOwner()) {
610 // Focus change was rejected. Unlikely, but possible.
611 dequeueKeyEvents(-1, newFocusOwner);
612 if (KeyboardFocusManager.isAutoFocusTransferEnabled()) {
613 restoreFocus(fe, newFocusedWindow);
614 }
615 break;
616 }
617 }
618
619 setNativeFocusOwner(getHeavyweight(newFocusOwner));
620
621 Component realOppositeComponent = this.realOppositeComponentWR.get();
622 if (realOppositeComponent != null &&
623 realOppositeComponent != fe.getOppositeComponent()) {
624 fe = new FocusEvent(newFocusOwner,
625 FocusEvent.FOCUS_GAINED,
626 fe.isTemporary(),
627 realOppositeComponent, fe.getCause());
628 ((AWTEvent) fe).isPosted = true;
629 }
630 return typeAheadAssertions(newFocusOwner, fe);
631 }
632
633 case FocusEvent.FOCUS_LOST: {
634 FocusEvent fe = (FocusEvent)e;
635 Component currentFocusOwner = getGlobalFocusOwner();
636 if (currentFocusOwner == null) {
637 if (focusLog.isLoggable(PlatformLogger.Level.FINE))
638 focusLog.fine("Skipping {0} because focus owner is null", e);
639 break;
640 }
641 // Ignore cases where a Component loses focus to itself.
642 // If we make a mistake because of retargeting, then the
643 // FOCUS_GAINED handler will correct it.
644 if (currentFocusOwner == fe.getOppositeComponent()) {
645 if (focusLog.isLoggable(PlatformLogger.Level.FINE))
646 focusLog.fine("Skipping {0} because current focus owner is equal to opposite", e);
647 break;
648 }
649
650 setGlobalFocusOwner(null);
651
652 if (getGlobalFocusOwner() != null) {
653 // Focus change was rejected. Unlikely, but possible.
654 restoreFocus(currentFocusOwner, true);
655 break;
656 }
657
658 if (!fe.isTemporary()) {
659 setGlobalPermanentFocusOwner(null);
660
661 if (getGlobalPermanentFocusOwner() != null) {
662 // Focus change was rejected. Unlikely, but possible.
663 restoreFocus(currentFocusOwner, true);
664 break;
665 }
666 } else {
667 Window owningWindow = currentFocusOwner.getContainingWindow();
668 if (owningWindow != null) {
669 owningWindow.setTemporaryLostComponent(currentFocusOwner);
670 }
671 }
672
673 setNativeFocusOwner(null);
674
675 fe.setSource(currentFocusOwner);
676
677 realOppositeComponentWR = (fe.getOppositeComponent() != null)
678 ? new WeakReference<Component>(currentFocusOwner)
679 : NULL_COMPONENT_WR;
680
681 return typeAheadAssertions(currentFocusOwner, fe);
682 }
683
684 case WindowEvent.WINDOW_DEACTIVATED: {
685 WindowEvent we = (WindowEvent)e;
686 Window currentActiveWindow = getGlobalActiveWindow();
687 if (currentActiveWindow == null) {
688 break;
689 }
690
691 if (currentActiveWindow != e.getSource()) {
692 // The event is lost in time.
693 // Allow listeners to precess the event but do not
694 // change any global states
695 break;
696 }
697
698 setGlobalActiveWindow(null);
699 if (getGlobalActiveWindow() != null) {
700 // Activation change was rejected. Unlikely, but possible.
701 break;
702 }
703
704 we.setSource(currentActiveWindow);
705 return typeAheadAssertions(currentActiveWindow, we);
706 }
707
708 case WindowEvent.WINDOW_LOST_FOCUS: {
709 if (repostIfFollowsKeyEvents((WindowEvent)e)) {
710 break;
711 }
712
713 WindowEvent we = (WindowEvent)e;
714 Window currentFocusedWindow = getGlobalFocusedWindow();
715 Window losingFocusWindow = we.getWindow();
716 Window activeWindow = getGlobalActiveWindow();
717 Window oppositeWindow = we.getOppositeWindow();
718 if (focusLog.isLoggable(PlatformLogger.Level.FINE))
719 focusLog.fine("Active {0}, Current focused {1}, losing focus {2} opposite {3}",
720 activeWindow, currentFocusedWindow,
721 losingFocusWindow, oppositeWindow);
722 if (currentFocusedWindow == null) {
723 break;
724 }
725
726 // Special case -- if the native windowing system posts an
727 // event claiming that the active Window has lost focus to the
728 // focused Window, then discard the event. This is an artifact
729 // of the native windowing system not knowing which Window is
730 // really focused.
731 if (inSendMessage == 0 && losingFocusWindow == activeWindow &&
732 oppositeWindow == currentFocusedWindow)
733 {
734 break;
735 }
736
737 Component currentFocusOwner = getGlobalFocusOwner();
738 if (currentFocusOwner != null) {
739 // The focus owner should always receive a FOCUS_LOST event
740 // before the Window is defocused.
741 Component oppositeComp = null;
742 if (oppositeWindow != null) {
743 oppositeComp = oppositeWindow.getTemporaryLostComponent();
744 if (oppositeComp == null) {
745 oppositeComp = oppositeWindow.getMostRecentFocusOwner();
746 }
747 }
748 if (oppositeComp == null) {
749 oppositeComp = oppositeWindow;
750 }
751 sendMessage(currentFocusOwner,
752 new FocusEvent(currentFocusOwner,
753 FocusEvent.FOCUS_LOST,
754 true,
755 oppositeComp, FocusEvent.Cause.ACTIVATION));
756 }
757
758 setGlobalFocusedWindow(null);
759 if (getGlobalFocusedWindow() != null) {
760 // Focus change was rejected. Unlikely, but possible.
761 restoreFocus(currentFocusedWindow, null, true);
762 break;
763 }
764
765 we.setSource(currentFocusedWindow);
766 realOppositeWindowWR = (oppositeWindow != null)
767 ? new WeakReference<Window>(currentFocusedWindow)
768 : NULL_WINDOW_WR;
769 typeAheadAssertions(currentFocusedWindow, we);
770
771 if (oppositeWindow == null) {
772 // Then we need to deactivate the active Window as well.
773 // No need to synthesize in other cases, because
774 // WINDOW_ACTIVATED will handle it if necessary.
775 sendMessage(activeWindow,
776 new WindowEvent(activeWindow,
777 WindowEvent.WINDOW_DEACTIVATED,
778 null));
779 if (getGlobalActiveWindow() != null) {
780 // Activation change was rejected. Unlikely,
781 // but possible.
782 restoreFocus(currentFocusedWindow, null, true);
783 }
784 }
785 break;
786 }
787
788 case KeyEvent.KEY_TYPED:
789 case KeyEvent.KEY_PRESSED:
790 case KeyEvent.KEY_RELEASED:
791 return typeAheadAssertions(null, e);
792
793 default:
794 return false;
795 }
796
797 return true;
798 }
799
800 /**
801 * Called by {@code dispatchEvent} if no other
802 * KeyEventDispatcher in the dispatcher chain dispatched the KeyEvent, or
803 * if no other KeyEventDispatchers are registered. If the event has not
804 * been consumed, its target is enabled, and the focus owner is not null,
805 * this method dispatches the event to its target. This method will also
806 * subsequently dispatch the event to all registered
807 * KeyEventPostProcessors. After all this operations are finished,
808 * the event is passed to peers for processing.
809 * <p>
810 * In all cases, this method returns {@code true}, since
811 * DefaultKeyboardFocusManager is designed so that neither
812 * {@code dispatchEvent}, nor the AWT event dispatcher, should take
813 * further action on the event in any situation.
814 *
815 * @param e the KeyEvent to be dispatched
816 * @return {@code true}
817 * @see Component#dispatchEvent
818 */
819 public boolean dispatchKeyEvent(KeyEvent e) {
820 Component focusOwner = (((AWTEvent)e).isPosted) ? getFocusOwner() : e.getComponent();
821
822 if (focusOwner != null && focusOwner.isShowing() && focusOwner.canBeFocusOwner()) {
823 if (!e.isConsumed()) {
824 Component comp = e.getComponent();
825 if (comp != null && comp.isEnabled()) {
826 redispatchEvent(comp, e);
827 }
828 }
829 }
830 boolean stopPostProcessing = false;
831 java.util.List<KeyEventPostProcessor> processors = getKeyEventPostProcessors();
832 if (processors != null) {
833 for (java.util.Iterator<KeyEventPostProcessor> iter = processors.iterator();
834 !stopPostProcessing && iter.hasNext(); )
835 {
836 stopPostProcessing = iter.next().
837 postProcessKeyEvent(e);
838 }
839 }
840 if (!stopPostProcessing) {
841 postProcessKeyEvent(e);
842 }
843
844 // Allow the peer to process KeyEvent
845 Component source = e.getComponent();
846 ComponentPeer peer = source.peer;
847
848 if (peer == null || peer instanceof LightweightPeer) {
849 // if focus owner is lightweight then its native container
850 // processes event
851 Container target = source.getNativeContainer();
852 if (target != null) {
853 peer = target.peer;
854 }
855 }
856 if (peer != null) {
857 peer.handleEvent(e);
858 }
859
860 return true;
861 }
862
863 /**
864 * This method will be called by {@code dispatchKeyEvent}. It will
865 * handle any unconsumed KeyEvents that map to an AWT
866 * {@code MenuShortcut} by consuming the event and activating the
867 * shortcut.
868 *
869 * @param e the KeyEvent to post-process
870 * @return {@code true}
871 * @see #dispatchKeyEvent
872 * @see MenuShortcut
873 */
874 public boolean postProcessKeyEvent(KeyEvent e) {
875 if (!e.isConsumed()) {
876 Component target = e.getComponent();
877 Container p = (Container)
878 (target instanceof Container ? target : target.getParent());
879 if (p != null) {
880 p.postProcessKeyEvent(e);
881 }
882 }
883 return true;
884 }
885
886 private void pumpApprovedKeyEvents() {
887 KeyEvent ke;
888 do {
889 ke = null;
890 synchronized (this) {
891 if (enqueuedKeyEvents.size() != 0) {
892 ke = enqueuedKeyEvents.getFirst();
893 if (typeAheadMarkers.size() != 0) {
894 TypeAheadMarker marker = typeAheadMarkers.getFirst();
895 // Fixed 5064013: may appears that the events have the same time
896 // if (ke.getWhen() >= marker.after) {
897 // The fix is rolled out.
898
899 if (ke.getWhen() > marker.after) {
900 ke = null;
901 }
902 }
903 if (ke != null) {
904 if (focusLog.isLoggable(PlatformLogger.Level.FINER)) {
905 focusLog.finer("Pumping approved event {0}", ke);
906 }
907 enqueuedKeyEvents.removeFirst();
908 }
909 }
910 }
911 if (ke != null) {
912 preDispatchKeyEvent(ke);
913 }
914 } while (ke != null);
915 }
916
917 /**
918 * Dumps the list of type-ahead queue markers to stderr
919 */
920 void dumpMarkers() {
921 if (focusLog.isLoggable(PlatformLogger.Level.FINEST)) {
922 focusLog.finest(">>> Markers dump, time: {0}", System.currentTimeMillis());
923 synchronized (this) {
924 if (typeAheadMarkers.size() != 0) {
925 Iterator<TypeAheadMarker> iter = typeAheadMarkers.iterator();
926 while (iter.hasNext()) {
927 TypeAheadMarker marker = iter.next();
928 focusLog.finest(" {0}", marker);
929 }
930 }
931 }
932 }
933 }
934
935 private boolean typeAheadAssertions(Component target, AWTEvent e) {
936
937 // Clear any pending events here as well as in the FOCUS_GAINED
938 // handler. We need this call here in case a marker was removed in
939 // response to a call to dequeueKeyEvents.
940 pumpApprovedKeyEvents();
941
942 switch (e.getID()) {
943 case KeyEvent.KEY_TYPED:
944 case KeyEvent.KEY_PRESSED:
945 case KeyEvent.KEY_RELEASED: {
946 KeyEvent ke = (KeyEvent)e;
947 synchronized (this) {
948 if (e.isPosted && typeAheadMarkers.size() != 0) {
949 TypeAheadMarker marker = typeAheadMarkers.getFirst();
950 // Fixed 5064013: may appears that the events have the same time
951 // if (ke.getWhen() >= marker.after) {
952 // The fix is rolled out.
953
954 if (ke.getWhen() > marker.after) {
955 if (focusLog.isLoggable(PlatformLogger.Level.FINER)) {
956 focusLog.finer("Storing event {0} because of marker {1}", ke, marker);
957 }
958 enqueuedKeyEvents.addLast(ke);
959 return true;
960 }
961 }
962 }
963
964 // KeyEvent was posted before focus change request
965 return preDispatchKeyEvent(ke);
966 }
967
968 case FocusEvent.FOCUS_GAINED:
969 if (focusLog.isLoggable(PlatformLogger.Level.FINEST)) {
970 focusLog.finest("Markers before FOCUS_GAINED on {0}", target);
971 }
972 dumpMarkers();
973 // Search the marker list for the first marker tied to
974 // the Component which just gained focus. Then remove
975 // that marker, any markers which immediately follow
976 // and are tied to the same component, and all markers
977 // that precede it. This handles the case where
978 // multiple focus requests were made for the same
979 // Component in a row and when we lost some of the
980 // earlier requests. Since FOCUS_GAINED events will
981 // not be generated for these additional requests, we
982 // need to clear those markers too.
983 synchronized (this) {
984 boolean found = false;
985 if (hasMarker(target)) {
986 for (Iterator<TypeAheadMarker> iter = typeAheadMarkers.iterator();
987 iter.hasNext(); )
988 {
989 if (iter.next().untilFocused == target) {
990 found = true;
991 } else if (found) {
992 break;
993 }
994 iter.remove();
995 }
996 } else {
997 // Exception condition - event without marker
998 if (focusLog.isLoggable(PlatformLogger.Level.FINER)) {
999 focusLog.finer("Event without marker {0}", e);
1000 }
1001 }
1002 }
1003 focusLog.finest("Markers after FOCUS_GAINED");
1004 dumpMarkers();
1005
1006 redispatchEvent(target, e);
1007
1008 // Now, dispatch any pending KeyEvents which have been
1009 // released because of the FOCUS_GAINED event so that we don't
1010 // have to wait for another event to be posted to the queue.
1011 pumpApprovedKeyEvents();
1012 return true;
1013
1014 default:
1015 redispatchEvent(target, e);
1016 return true;
1017 }
1018 }
1019
1020 /**
1021 * Returns true if there are some marker associated with component {@code comp}
1022 * in a markers' queue
1023 * @since 1.5
1024 */
1025 private boolean hasMarker(Component comp) {
1026 for (Iterator<TypeAheadMarker> iter = typeAheadMarkers.iterator(); iter.hasNext(); ) {
1027 if (iter.next().untilFocused == comp) {
1028 return true;
1029 }
1030 }
1031 return false;
1032 }
1033
1034 /**
1035 * Clears markers queue
1036 * @since 1.5
1037 */
1038 void clearMarkers() {
1039 synchronized(this) {
1040 typeAheadMarkers.clear();
1041 }
1042 }
1043
1044 @SuppressWarnings("deprecation")
1045 private boolean preDispatchKeyEvent(KeyEvent ke) {
1046 if (((AWTEvent) ke).isPosted) {
1047 Component focusOwner = getFocusOwner();
1048 ke.setSource(((focusOwner != null) ? focusOwner : getFocusedWindow()));
1049 }
1050 if (ke.getSource() == null) {
1051 return true;
1052 }
1053
1054 // Explicitly set the key event timestamp here (not in Component.dispatchEventImpl):
1055 // - A key event is anyway passed to this method which starts its actual dispatching.
1056 // - If a key event is put to the type ahead queue, its time stamp should not be registered
1057 // until its dispatching actually starts (by this method).
1058 EventQueue.setCurrentEventAndMostRecentTime(ke);
1059
1060 /**
1061 * Fix for 4495473.
1062 * This fix allows to correctly dispatch events when native
1063 * event proxying mechanism is active.
1064 * If it is active we should redispatch key events after
1065 * we detected its correct target.
1066 */
1067 if (KeyboardFocusManager.isProxyActive(ke)) {
1068 Component source = (Component)ke.getSource();
1069 Container target = source.getNativeContainer();
1070 if (target != null) {
1071 ComponentPeer peer = target.peer;
1072 if (peer != null) {
1073 peer.handleEvent(ke);
1074 /**
1075 * Fix for 4478780 - consume event after it was dispatched by peer.
1076 */
1077 ke.consume();
1078 }
1079 }
1080 return true;
1081 }
1082
1083 java.util.List<KeyEventDispatcher> dispatchers = getKeyEventDispatchers();
1084 if (dispatchers != null) {
1085 for (java.util.Iterator<KeyEventDispatcher> iter = dispatchers.iterator();
1086 iter.hasNext(); )
1087 {
1088 if (iter.next().
1089 dispatchKeyEvent(ke))
1090 {
1091 return true;
1092 }
1093 }
1094 }
1095 return dispatchKeyEvent(ke);
1096 }
1097
1098 /*
1099 * @param e is a KEY_PRESSED event that can be used
1100 * to track the next KEY_TYPED related.
1101 */
1102 private void consumeNextKeyTyped(KeyEvent e) {
1103 consumeNextKeyTyped = true;
1104 }
1105
1106 private void consumeTraversalKey(KeyEvent e) {
1107 e.consume();
1108 consumeNextKeyTyped = (e.getID() == KeyEvent.KEY_PRESSED) &&
1109 !e.isActionKey();
1110 }
1111
1112 /*
1113 * return true if event was consumed
1114 */
1115 private boolean consumeProcessedKeyEvent(KeyEvent e) {
1116 if ((e.getID() == KeyEvent.KEY_TYPED) && consumeNextKeyTyped) {
1117 e.consume();
1118 consumeNextKeyTyped = false;
1119 return true;
1120 }
1121 return false;
1122 }
1123
1124 /**
1125 * This method initiates a focus traversal operation if and only if the
1126 * KeyEvent represents a focus traversal key for the specified
1127 * focusedComponent. It is expected that focusedComponent is the current
1128 * focus owner, although this need not be the case. If it is not,
1129 * focus traversal will nevertheless proceed as if focusedComponent
1130 * were the focus owner.
1131 *
1132 * @param focusedComponent the Component that is the basis for a focus
1133 * traversal operation if the specified event represents a focus
1134 * traversal key for the Component
1135 * @param e the event that may represent a focus traversal key
1136 */
1137 public void processKeyEvent(Component focusedComponent, KeyEvent e) {
1138 // consume processed event if needed
1139 if (consumeProcessedKeyEvent(e)) {
1140 return;
1141 }
1142
1143 // KEY_TYPED events cannot be focus traversal keys
1144 if (e.getID() == KeyEvent.KEY_TYPED) {
1145 return;
1146 }
1147
1148 if (focusedComponent.getFocusTraversalKeysEnabled() &&
1149 !e.isConsumed())
1150 {
1151 AWTKeyStroke stroke = AWTKeyStroke.getAWTKeyStrokeForEvent(e),
1152 oppStroke = AWTKeyStroke.getAWTKeyStroke(stroke.getKeyCode(),
1153 stroke.getModifiers(),
1154 !stroke.isOnKeyRelease());
1155 Set<AWTKeyStroke> toTest;
1156 boolean contains, containsOpp;
1157
1158 toTest = focusedComponent.getFocusTraversalKeys(
1159 KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS);
1160 contains = toTest.contains(stroke);
1161 containsOpp = toTest.contains(oppStroke);
1162
1163 if (contains || containsOpp) {
1164 consumeTraversalKey(e);
1165 if (contains) {
1166 focusNextComponent(focusedComponent);
1167 }
1168 return;
1169 } else if (e.getID() == KeyEvent.KEY_PRESSED) {
1170 // Fix for 6637607: consumeNextKeyTyped should be reset.
1171 consumeNextKeyTyped = false;
1172 }
1173
1174 toTest = focusedComponent.getFocusTraversalKeys(
1175 KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS);
1176 contains = toTest.contains(stroke);
1177 containsOpp = toTest.contains(oppStroke);
1178
1179 if (contains || containsOpp) {
1180 consumeTraversalKey(e);
1181 if (contains) {
1182 focusPreviousComponent(focusedComponent);
1183 }
1184 return;
1185 }
1186
1187 toTest = focusedComponent.getFocusTraversalKeys(
1188 KeyboardFocusManager.UP_CYCLE_TRAVERSAL_KEYS);
1189 contains = toTest.contains(stroke);
1190 containsOpp = toTest.contains(oppStroke);
1191
1192 if (contains || containsOpp) {
1193 consumeTraversalKey(e);
1194 if (contains) {
1195 upFocusCycle(focusedComponent);
1196 }
1197 return;
1198 }
1199
1200 if (!((focusedComponent instanceof Container) &&
1201 ((Container)focusedComponent).isFocusCycleRoot())) {
1202 return;
1203 }
1204
1205 toTest = focusedComponent.getFocusTraversalKeys(
1206 KeyboardFocusManager.DOWN_CYCLE_TRAVERSAL_KEYS);
1207 contains = toTest.contains(stroke);
1208 containsOpp = toTest.contains(oppStroke);
1209
1210 if (contains || containsOpp) {
1211 consumeTraversalKey(e);
1212 if (contains) {
1213 downFocusCycle((Container)focusedComponent);
1214 }
1215 }
1216 }
1217 }
1218
1219 /**
1220 * Delays dispatching of KeyEvents until the specified Component becomes
1221 * the focus owner. KeyEvents with timestamps later than the specified
1222 * timestamp will be enqueued until the specified Component receives a
1223 * FOCUS_GAINED event, or the AWT cancels the delay request by invoking
1224 * {@code dequeueKeyEvents} or {@code discardKeyEvents}.
1225 *
1226 * @param after timestamp of current event, or the current, system time if
1227 * the current event has no timestamp, or the AWT cannot determine
1228 * which event is currently being handled
1229 * @param untilFocused Component which will receive a FOCUS_GAINED event
1230 * before any pending KeyEvents
1231 * @see #dequeueKeyEvents
1232 * @see #discardKeyEvents
1233 */
1234 protected synchronized void enqueueKeyEvents(long after,
1235 Component untilFocused) {
1236 if (untilFocused == null) {
1237 return;
1238 }
1239
1240 if (focusLog.isLoggable(PlatformLogger.Level.FINER)) {
1241 focusLog.finer("Enqueue at {0} for {1}",
1242 after, untilFocused);
1243 }
1244
1245 int insertionIndex = 0,
1246 i = typeAheadMarkers.size();
1247 ListIterator<TypeAheadMarker> iter = typeAheadMarkers.listIterator(i);
1248
1249 for (; i > 0; i--) {
1250 TypeAheadMarker marker = iter.previous();
1251 if (marker.after <= after) {
1252 insertionIndex = i;
1253 break;
1254 }
1255 }
1256
1257 typeAheadMarkers.add(insertionIndex,
1258 new TypeAheadMarker(after, untilFocused));
1259 }
1260
1261 /**
1262 * Releases for normal dispatching to the current focus owner all
1263 * KeyEvents which were enqueued because of a call to
1264 * {@code enqueueKeyEvents} with the same timestamp and Component.
1265 * If the given timestamp is less than zero, the outstanding enqueue
1266 * request for the given Component with the <b>oldest</b> timestamp (if
1267 * any) should be cancelled.
1268 *
1269 * @param after the timestamp specified in the call to
1270 * {@code enqueueKeyEvents}, or any value < 0
1271 * @param untilFocused the Component specified in the call to
1272 * {@code enqueueKeyEvents}
1273 * @see #enqueueKeyEvents
1274 * @see #discardKeyEvents
1275 */
1276 protected synchronized void dequeueKeyEvents(long after,
1277 Component untilFocused) {
1278 if (untilFocused == null) {
1279 return;
1280 }
1281
1282 if (focusLog.isLoggable(PlatformLogger.Level.FINER)) {
1283 focusLog.finer("Dequeue at {0} for {1}",
1284 after, untilFocused);
1285 }
1286
1287 TypeAheadMarker marker;
1288 ListIterator<TypeAheadMarker> iter = typeAheadMarkers.listIterator
1289 ((after >= 0) ? typeAheadMarkers.size() : 0);
1290
1291 if (after < 0) {
1292 while (iter.hasNext()) {
1293 marker = iter.next();
1294 if (marker.untilFocused == untilFocused)
1295 {
1296 iter.remove();
1297 return;
1298 }
1299 }
1300 } else {
1301 while (iter.hasPrevious()) {
1302 marker = iter.previous();
1303 if (marker.untilFocused == untilFocused &&
1304 marker.after == after)
1305 {
1306 iter.remove();
1307 return;
1308 }
1309 }
1310 }
1311 }
1312
1313 /**
1314 * Discards all KeyEvents which were enqueued because of one or more calls
1315 * to {@code enqueueKeyEvents} with the specified Component, or one of
1316 * its descendants.
1317 *
1318 * @param comp the Component specified in one or more calls to
1319 * {@code enqueueKeyEvents}, or a parent of such a Component
1320 * @see #enqueueKeyEvents
1321 * @see #dequeueKeyEvents
1322 */
1323 protected synchronized void discardKeyEvents(Component comp) {
1324 if (comp == null) {
1325 return;
1326 }
1327
1328 long start = -1;
1329
1330 for (Iterator<TypeAheadMarker> iter = typeAheadMarkers.iterator(); iter.hasNext(); ) {
1331 TypeAheadMarker marker = iter.next();
1332 Component toTest = marker.untilFocused;
1333 boolean match = (toTest == comp);
1334 while (!match && toTest != null && !(toTest instanceof Window)) {
1335 toTest = toTest.getParent();
1336 match = (toTest == comp);
1337 }
1338 if (match) {
1339 if (start < 0) {
1340 start = marker.after;
1341 }
1342 iter.remove();
1343 } else if (start >= 0) {
1344 purgeStampedEvents(start, marker.after);
1345 start = -1;
1346 }
1347 }
1348
1349 purgeStampedEvents(start, -1);
1350 }
1351
1352 // Notes:
1353 // * must be called inside a synchronized block
1354 // * if 'start' is < 0, then this function does nothing
1355 // * if 'end' is < 0, then all KeyEvents from 'start' to the end of the
1356 // queue will be removed
1357 private void purgeStampedEvents(long start, long end) {
1358 if (start < 0) {
1359 return;
1360 }
1361
1362 for (Iterator<KeyEvent> iter = enqueuedKeyEvents.iterator(); iter.hasNext(); ) {
1363 KeyEvent ke = iter.next();
1364 long time = ke.getWhen();
1365
1366 if (start < time && (end < 0 || time <= end)) {
1367 iter.remove();
1368 }
1369
1370 if (end >= 0 && time > end) {
1371 break;
1372 }
1373 }
1374 }
1375
1376 /**
1377 * Focuses the Component before aComponent, typically based on a
1378 * FocusTraversalPolicy.
1379 *
1380 * @param aComponent the Component that is the basis for the focus
1381 * traversal operation
1382 * @see FocusTraversalPolicy
1383 * @see Component#transferFocusBackward
1384 */
1385 public void focusPreviousComponent(Component aComponent) {
1386 if (aComponent != null) {
1387 aComponent.transferFocusBackward();
1388 }
1389 }
1390
1391 /**
1392 * Focuses the Component after aComponent, typically based on a
1393 * FocusTraversalPolicy.
1394 *
1395 * @param aComponent the Component that is the basis for the focus
1396 * traversal operation
1397 * @see FocusTraversalPolicy
1398 * @see Component#transferFocus
1399 */
1400 public void focusNextComponent(Component aComponent) {
1401 if (aComponent != null) {
1402 aComponent.transferFocus();
1403 }
1404 }
1405
1406 /**
1407 * Moves the focus up one focus traversal cycle. Typically, the focus owner
1408 * is set to aComponent's focus cycle root, and the current focus cycle
1409 * root is set to the new focus owner's focus cycle root. If, however,
1410 * aComponent's focus cycle root is a Window, then the focus owner is set
1411 * to the focus cycle root's default Component to focus, and the current
1412 * focus cycle root is unchanged.
1413 *
1414 * @param aComponent the Component that is the basis for the focus
1415 * traversal operation
1416 * @see Component#transferFocusUpCycle
1417 */
1418 public void upFocusCycle(Component aComponent) {
1419 if (aComponent != null) {
1420 aComponent.transferFocusUpCycle();
1421 }
1422 }
1423
1424 /**
1425 * Moves the focus down one focus traversal cycle. If aContainer is a focus
1426 * cycle root, then the focus owner is set to aContainer's default
1427 * Component to focus, and the current focus cycle root is set to
1428 * aContainer. If aContainer is not a focus cycle root, then no focus
1429 * traversal operation occurs.
1430 *
1431 * @param aContainer the Container that is the basis for the focus
1432 * traversal operation
1433 * @see Container#transferFocusDownCycle
1434 */
1435 public void downFocusCycle(Container aContainer) {
1436 if (aContainer != null && aContainer.isFocusCycleRoot()) {
1437 aContainer.transferFocusDownCycle();
1438 }
1439 }
1440 }