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My first initial commit with all of mine experimental changes.

Dmitry Kabak (userdima committed 13 years ago

Commit d37b88d1 parent 3f5b46618352 files · +2598093 −-8690Browse files

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1+/*
2+ * Copyright (c) 2000, 2003, 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.util.List;
28+import java.util.ArrayList;
29+import sun.util.logging.PlatformLogger;
30+
31+/**
32+ * A FocusTraversalPolicy that determines traversal order based on the order
33+ * of child Components in a Container. From a particular focus cycle root, the
34+ * policy makes a pre-order traversal of the Component hierarchy, and traverses
35+ * a Container's children according to the ordering of the array returned by
36+ * <code>Container.getComponents()</code>. Portions of the hierarchy that are
37+ * not visible and displayable will not be searched.
38+ * <p>
39+ * By default, ContainerOrderFocusTraversalPolicy implicitly transfers focus
40+ * down-cycle. That is, during normal forward focus traversal, the Component
41+ * traversed after a focus cycle root will be the focus-cycle-root's default
42+ * Component to focus. This behavior can be disabled using the
43+ * <code>setImplicitDownCycleTraversal</code> method.
44+ * <p>
45+ * By default, methods of this class with return a Component only if it is
46+ * visible, displayable, enabled, and focusable. Subclasses can modify this
47+ * behavior by overriding the <code>accept</code> method.
48+ * <p>
49+ * This policy takes into account <a
50+ * href="doc-files/FocusSpec.html#FocusTraversalPolicyProviders">focus traversal
51+ * policy providers</a>. When searching for first/last/next/previous Component,
52+ * if a focus traversal policy provider is encountered, its focus traversal
53+ * policy is used to perform the search operation.
54+ *
55+ * @author David Mendenhall
56+ *
57+ * @see Container#getComponents
58+ * @since 1.4
59+ */
60+public class ContainerOrderFocusTraversalPolicy extends FocusTraversalPolicy
61+ implements java.io.Serializable
62+{
63+ private static final PlatformLogger log = PlatformLogger.getLogger("java.awt.ContainerOrderFocusTraversalPolicy");
64+
65+ final private int FORWARD_TRAVERSAL = 0;
66+ final private int BACKWARD_TRAVERSAL = 1;
67+
68+ /*
69+ * JDK 1.4 serialVersionUID
70+ */
71+ private static final long serialVersionUID = 486933713763926351L;
72+
73+ private boolean implicitDownCycleTraversal = true;
74+
75+ /**
76+ * Used by getComponentAfter and getComponentBefore for efficiency. In
77+ * order to maintain compliance with the specification of
78+ * FocusTraversalPolicy, if traversal wraps, we should invoke
79+ * getFirstComponent or getLastComponent. These methods may be overriden in
80+ * subclasses to behave in a non-generic way. However, in the generic case,
81+ * these methods will simply return the first or last Components of the
82+ * sorted list, respectively. Since getComponentAfter and
83+ * getComponentBefore have already built the list before determining
84+ * that they need to invoke getFirstComponent or getLastComponent, the
85+ * list should be reused if possible.
86+ */
87+ transient private Container cachedRoot;
88+ transient private List cachedCycle;
89+
90+ /*
91+ * We suppose to use getFocusTraversalCycle & getComponentIndex methods in order
92+ * to divide the policy into two parts:
93+ * 1) Making the focus traversal cycle.
94+ * 2) Traversing the cycle.
95+ * The 1st point assumes producing a list of components representing the focus
96+ * traversal cycle. The two methods mentioned above should implement this logic.
97+ * The 2nd point assumes implementing the common concepts of operating on the
98+ * cycle: traversing back and forth, retrieving the initial/default/first/last
99+ * component. These concepts are described in the AWT Focus Spec and they are
100+ * applied to the FocusTraversalPolicy in general.
101+ * Thus, a descendant of this policy may wish to not reimplement the logic of
102+ * the 2nd point but just override the implementation of the 1st one.
103+ * A striking example of such a descendant is the javax.swing.SortingFocusTraversalPolicy.
104+ */
105+ /*protected*/ private List<Component> getFocusTraversalCycle(Container aContainer) {
106+ List<Component> cycle = new ArrayList<Component>();
107+ enumerateCycle(aContainer, cycle);
108+ return cycle;
109+ }
110+ /*protected*/ private int getComponentIndex(List<Component> cycle, Component aComponent) {
111+ return cycle.indexOf(aComponent);
112+ }
113+
114+ private void enumerateCycle(Container container, List cycle) {
115+ if (!(container.isVisible() && container.isDisplayable())) {
116+ return;
117+ }
118+
119+ cycle.add(container);
120+
121+ Component[] components = container.getComponents();
122+ for (int i = 0; i < components.length; i++) {
123+ Component comp = components[i];
124+ if (comp instanceof Container) {
125+ Container cont = (Container)comp;
126+
127+ if (!cont.isFocusCycleRoot() && !cont.isFocusTraversalPolicyProvider()) {
128+ enumerateCycle(cont, cycle);
129+ continue;
130+ }
131+ }
132+ cycle.add(comp);
133+ }
134+ }
135+
136+ private Container getTopmostProvider(Container focusCycleRoot, Component aComponent) {
137+ Container aCont = aComponent.getParent();
138+ Container ftp = null;
139+ while (aCont != focusCycleRoot && aCont != null) {
140+ if (aCont.isFocusTraversalPolicyProvider()) {
141+ ftp = aCont;
142+ }
143+ aCont = aCont.getParent();
144+ }
145+ if (aCont == null) {
146+ return null;
147+ }
148+ return ftp;
149+ }
150+
151+ /*
152+ * Checks if a new focus cycle takes place and returns a Component to traverse focus to.
153+ * @param comp a possible focus cycle root or policy provider
154+ * @param traversalDirection the direction of the traversal
155+ * @return a Component to traverse focus to if {@code comp} is a root or provider
156+ * and implicit down-cycle is set, otherwise {@code null}
157+ */
158+ private Component getComponentDownCycle(Component comp, int traversalDirection) {
159+ Component retComp = null;
160+
161+ if (comp instanceof Container) {
162+ Container cont = (Container)comp;
163+
164+ if (cont.isFocusCycleRoot()) {
165+ if (getImplicitDownCycleTraversal()) {
166+ retComp = cont.getFocusTraversalPolicy().getDefaultComponent(cont);
167+
168+ if (retComp != null && log.isLoggable(PlatformLogger.FINE)) {
169+ log.fine("### Transfered focus down-cycle to " + retComp +
170+ " in the focus cycle root " + cont);
171+ }
172+ } else {
173+ return null;
174+ }
175+ } else if (cont.isFocusTraversalPolicyProvider()) {
176+ retComp = (traversalDirection == FORWARD_TRAVERSAL ?
177+ cont.getFocusTraversalPolicy().getDefaultComponent(cont) :
178+ cont.getFocusTraversalPolicy().getLastComponent(cont));
179+
180+ if (retComp != null && log.isLoggable(PlatformLogger.FINE)) {
181+ log.fine("### Transfered focus to " + retComp + " in the FTP provider " + cont);
182+ }
183+ }
184+ }
185+ return retComp;
186+ }
187+
188+ /**
189+ * Returns the Component that should receive the focus after aComponent.
190+ * aContainer must be a focus cycle root of aComponent or a focus traversal policy provider.
191+ * <p>
192+ * By default, ContainerOrderFocusTraversalPolicy implicitly transfers
193+ * focus down-cycle. That is, during normal forward focus traversal, the
194+ * Component traversed after a focus cycle root will be the focus-cycle-
195+ * root's default Component to focus. This behavior can be disabled using
196+ * the <code>setImplicitDownCycleTraversal</code> method.
197+ * <p>
198+ * If aContainer is <a href="doc-files/FocusSpec.html#FocusTraversalPolicyProviders">focus
199+ * traversal policy provider</a>, the focus is always transferred down-cycle.
200+ *
201+ * @param aContainer a focus cycle root of aComponent or a focus traversal policy provider
202+ * @param aComponent a (possibly indirect) child of aContainer, or
203+ * aContainer itself
204+ * @return the Component that should receive the focus after aComponent, or
205+ * null if no suitable Component can be found
206+ * @throws IllegalArgumentException if aContainer is not a focus cycle
207+ * root of aComponent or focus traversal policy provider, or if either aContainer or
208+ * aComponent is null
209+ */
210+ public Component getComponentAfter(Container aContainer, Component aComponent) {
211+ if (log.isLoggable(PlatformLogger.FINE)) log.fine("### Searching in " + aContainer + " for component after " + aComponent);
212+
213+ if (aContainer == null || aComponent == null) {
214+ throw new IllegalArgumentException("aContainer and aComponent cannot be null");
215+ }
216+ if (!aContainer.isFocusTraversalPolicyProvider() && !aContainer.isFocusCycleRoot()) {
217+ throw new IllegalArgumentException("aContainer should be focus cycle root or focus traversal policy provider");
218+
219+ } else if (aContainer.isFocusCycleRoot() && !aComponent.isFocusCycleRoot(aContainer)) {
220+ throw new IllegalArgumentException("aContainer is not a focus cycle root of aComponent");
221+ }
222+
223+ synchronized(aContainer.getTreeLock()) {
224+
225+ if (!(aContainer.isVisible() && aContainer.isDisplayable())) {
226+ return null;
227+ }
228+
229+ // Before all the ckecks below we first see if it's an FTP provider or a focus cycle root.
230+ // If it's the case just go down cycle (if it's set to "implicit").
231+ Component comp = getComponentDownCycle(aComponent, FORWARD_TRAVERSAL);
232+ if (comp != null) {
233+ return comp;
234+ }
235+
236+ // See if the component is inside of policy provider.
237+ Container provider = getTopmostProvider(aContainer, aComponent);
238+ if (provider != null) {
239+ if (log.isLoggable(PlatformLogger.FINE)) {
240+ log.fine("### Asking FTP " + provider + " for component after " + aComponent);
241+ }
242+
243+ // FTP knows how to find component after the given. We don't.
244+ FocusTraversalPolicy policy = provider.getFocusTraversalPolicy();
245+ Component afterComp = policy.getComponentAfter(provider, aComponent);
246+
247+ // Null result means that we overstepped the limit of the FTP's cycle.
248+ // In that case we must quit the cycle, otherwise return the component found.
249+ if (afterComp != null) {
250+ if (log.isLoggable(PlatformLogger.FINE)) log.fine("### FTP returned " + afterComp);
251+ return afterComp;
252+ }
253+ aComponent = provider;
254+ }
255+
256+ List<Component> cycle = getFocusTraversalCycle(aContainer);
257+
258+ if (log.isLoggable(PlatformLogger.FINE)) log.fine("### Cycle is " + cycle + ", component is " + aComponent);
259+
260+ int index = getComponentIndex(cycle, aComponent);
261+
262+ if (index < 0) {
263+ if (log.isLoggable(PlatformLogger.FINE)) {
264+ log.fine("### Didn't find component " + aComponent + " in a cycle " + aContainer);
265+ }
266+ return getFirstComponent(aContainer);
267+ }
268+
269+ for (index++; index < cycle.size(); index++) {
270+ comp = cycle.get(index);
271+ if (accept(comp)) {
272+ return comp;
273+ } else if ((comp = getComponentDownCycle(comp, FORWARD_TRAVERSAL)) != null) {
274+ return comp;
275+ }
276+ }
277+
278+ if (aContainer.isFocusCycleRoot()) {
279+ this.cachedRoot = aContainer;
280+ this.cachedCycle = cycle;
281+
282+ comp = getFirstComponent(aContainer);
283+
284+ this.cachedRoot = null;
285+ this.cachedCycle = null;
286+
287+ return comp;
288+ }
289+ }
290+ return null;
291+ }
292+
293+ /**
294+ * Returns the Component that should receive the focus before aComponent.
295+ * aContainer must be a focus cycle root of aComponent or a <a
296+ * href="doc-files/FocusSpec.html#FocusTraversalPolicyProviders">focus traversal policy
297+ * provider</a>.
298+ *
299+ * @param aContainer a focus cycle root of aComponent or focus traversal policy provider
300+ * @param aComponent a (possibly indirect) child of aContainer, or
301+ * aContainer itself
302+ * @return the Component that should receive the focus before aComponent,
303+ * or null if no suitable Component can be found
304+ * @throws IllegalArgumentException if aContainer is not a focus cycle
305+ * root of aComponent or focus traversal policy provider, or if either aContainer or
306+ * aComponent is null
307+ */
308+ public Component getComponentBefore(Container aContainer, Component aComponent) {
309+ if (aContainer == null || aComponent == null) {
310+ throw new IllegalArgumentException("aContainer and aComponent cannot be null");
311+ }
312+ if (!aContainer.isFocusTraversalPolicyProvider() && !aContainer.isFocusCycleRoot()) {
313+ throw new IllegalArgumentException("aContainer should be focus cycle root or focus traversal policy provider");
314+
315+ } else if (aContainer.isFocusCycleRoot() && !aComponent.isFocusCycleRoot(aContainer)) {
316+ throw new IllegalArgumentException("aContainer is not a focus cycle root of aComponent");
317+ }
318+
319+ synchronized(aContainer.getTreeLock()) {
320+
321+ if (!(aContainer.isVisible() && aContainer.isDisplayable())) {
322+ return null;
323+ }
324+
325+ // See if the component is inside of policy provider.
326+ Container provider = getTopmostProvider(aContainer, aComponent);
327+ if (provider != null) {
328+ if (log.isLoggable(PlatformLogger.FINE)) {
329+ log.fine("### Asking FTP " + provider + " for component after " + aComponent);
330+ }
331+
332+ // FTP knows how to find component after the given. We don't.
333+ FocusTraversalPolicy policy = provider.getFocusTraversalPolicy();
334+ Component beforeComp = policy.getComponentBefore(provider, aComponent);
335+
336+ // Null result means that we overstepped the limit of the FTP's cycle.
337+ // In that case we must quit the cycle, otherwise return the component found.
338+ if (beforeComp != null) {
339+ if (log.isLoggable(PlatformLogger.FINE)) log.fine("### FTP returned " + beforeComp);
340+ return beforeComp;
341+ }
342+ aComponent = provider;
343+
344+ // If the provider is traversable it's returned.
345+ if (accept(aComponent)) {
346+ return aComponent;
347+ }
348+ }
349+
350+ List<Component> cycle = getFocusTraversalCycle(aContainer);
351+
352+ if (log.isLoggable(PlatformLogger.FINE)) log.fine("### Cycle is " + cycle + ", component is " + aComponent);
353+
354+ int index = getComponentIndex(cycle, aComponent);
355+
356+ if (index < 0) {
357+ if (log.isLoggable(PlatformLogger.FINE)) {
358+ log.fine("### Didn't find component " + aComponent + " in a cycle " + aContainer);
359+ }
360+ return getLastComponent(aContainer);
361+ }
362+
363+ Component comp = null;
364+ Component tryComp = null;
365+
366+ for (index--; index>=0; index--) {
367+ comp = cycle.get(index);
368+ if (comp != aContainer && (tryComp = getComponentDownCycle(comp, BACKWARD_TRAVERSAL)) != null) {
369+ return tryComp;
370+ } else if (accept(comp)) {
371+ return comp;
372+ }
373+ }
374+
375+ if (aContainer.isFocusCycleRoot()) {
376+ this.cachedRoot = aContainer;
377+ this.cachedCycle = cycle;
378+
379+ comp = getLastComponent(aContainer);
380+
381+ this.cachedRoot = null;
382+ this.cachedCycle = null;
383+
384+ return comp;
385+ }
386+ }
387+ return null;
388+ }
389+
390+ /**
391+ * Returns the first Component in the traversal cycle. This method is used
392+ * to determine the next Component to focus when traversal wraps in the
393+ * forward direction.
394+ *
395+ * @param aContainer the focus cycle root or focus traversal policy provider whose first
396+ * Component is to be returned
397+ * @return the first Component in the traversal cycle of aContainer,
398+ * or null if no suitable Component can be found
399+ * @throws IllegalArgumentException if aContainer is null
400+ */
401+ public Component getFirstComponent(Container aContainer) {
402+ List<Component> cycle;
403+
404+ if (log.isLoggable(PlatformLogger.FINE)) log.fine("### Getting first component in " + aContainer);
405+ if (aContainer == null) {
406+ throw new IllegalArgumentException("aContainer cannot be null");
407+
408+ }
409+
410+ synchronized(aContainer.getTreeLock()) {
411+
412+ if (!(aContainer.isVisible() && aContainer.isDisplayable())) {
413+ return null;
414+ }
415+
416+ if (this.cachedRoot == aContainer) {
417+ cycle = this.cachedCycle;
418+ } else {
419+ cycle = getFocusTraversalCycle(aContainer);
420+ }
421+
422+ if (cycle.size() == 0) {
423+ if (log.isLoggable(PlatformLogger.FINE)) log.fine("### Cycle is empty");
424+ return null;
425+ }
426+ if (log.isLoggable(PlatformLogger.FINE)) log.fine("### Cycle is " + cycle);
427+
428+ for (Component comp : cycle) {
429+ if (accept(comp)) {
430+ return comp;
431+ } else if (comp != aContainer &&
432+ (comp = getComponentDownCycle(comp, FORWARD_TRAVERSAL)) != null)
433+ {
434+ return comp;
435+ }
436+ }
437+ }
438+ return null;
439+ }
440+
441+ /**
442+ * Returns the last Component in the traversal cycle. This method is used
443+ * to determine the next Component to focus when traversal wraps in the
444+ * reverse direction.
445+ *
446+ * @param aContainer the focus cycle root or focus traversal policy provider whose last
447+ * Component is to be returned
448+ * @return the last Component in the traversal cycle of aContainer,
449+ * or null if no suitable Component can be found
450+ * @throws IllegalArgumentException if aContainer is null
451+ */
452+ public Component getLastComponent(Container aContainer) {
453+ List<Component> cycle;
454+ if (log.isLoggable(PlatformLogger.FINE)) log.fine("### Getting last component in " + aContainer);
455+
456+ if (aContainer == null) {
457+ throw new IllegalArgumentException("aContainer cannot be null");
458+ }
459+
460+ synchronized(aContainer.getTreeLock()) {
461+
462+ if (!(aContainer.isVisible() && aContainer.isDisplayable())) {
463+ return null;
464+ }
465+
466+ if (this.cachedRoot == aContainer) {
467+ cycle = this.cachedCycle;
468+ } else {
469+ cycle = getFocusTraversalCycle(aContainer);
470+ }
471+
472+ if (cycle.size() == 0) {
473+ if (log.isLoggable(PlatformLogger.FINE)) log.fine("### Cycle is empty");
474+ return null;
475+ }
476+ if (log.isLoggable(PlatformLogger.FINE)) log.fine("### Cycle is " + cycle);
477+
478+ for (int i= cycle.size() - 1; i >= 0; i--) {
479+ Component comp = cycle.get(i);
480+ if (accept(comp)) {
481+ return comp;
482+ } else if (comp instanceof Container && comp != aContainer) {
483+ Container cont = (Container)comp;
484+ if (cont.isFocusTraversalPolicyProvider()) {
485+ return cont.getFocusTraversalPolicy().getLastComponent(cont);
486+ }
487+ }
488+ }
489+ }
490+ return null;
491+ }
492+
493+ /**
494+ * Returns the default Component to focus. This Component will be the first
495+ * to receive focus when traversing down into a new focus traversal cycle
496+ * rooted at aContainer. The default implementation of this method
497+ * returns the same Component as <code>getFirstComponent</code>.
498+ *
499+ * @param aContainer the focus cycle root or focus traversal policy provider whose default
500+ * Component is to be returned
501+ * @return the default Component in the traversal cycle of aContainer,
502+ * or null if no suitable Component can be found
503+ * @see #getFirstComponent
504+ * @throws IllegalArgumentException if aContainer is null
505+ */
506+ public Component getDefaultComponent(Container aContainer) {
507+ return getFirstComponent(aContainer);
508+ }
509+
510+ /**
511+ * Sets whether this ContainerOrderFocusTraversalPolicy transfers focus
512+ * down-cycle implicitly. If <code>true</code>, during normal forward focus
513+ * traversal, the Component traversed after a focus cycle root will be the
514+ * focus-cycle-root's default Component to focus. If <code>false</code>,
515+ * the next Component in the focus traversal cycle rooted at the specified
516+ * focus cycle root will be traversed instead. The default value for this
517+ * property is <code>true</code>.
518+ *
519+ * @param implicitDownCycleTraversal whether this
520+ * ContainerOrderFocusTraversalPolicy transfers focus down-cycle
521+ * implicitly
522+ * @see #getImplicitDownCycleTraversal
523+ * @see #getFirstComponent
524+ */
525+ public void setImplicitDownCycleTraversal(boolean implicitDownCycleTraversal) {
526+ this.implicitDownCycleTraversal = implicitDownCycleTraversal;
527+ }
528+
529+ /**
530+ * Returns whether this ContainerOrderFocusTraversalPolicy transfers focus
531+ * down-cycle implicitly. If <code>true</code>, during normal forward focus
532+ * traversal, the Component traversed after a focus cycle root will be the
533+ * focus-cycle-root's default Component to focus. If <code>false</code>,
534+ * the next Component in the focus traversal cycle rooted at the specified
535+ * focus cycle root will be traversed instead.
536+ *
537+ * @return whether this ContainerOrderFocusTraversalPolicy transfers focus
538+ * down-cycle implicitly
539+ * @see #setImplicitDownCycleTraversal
540+ * @see #getFirstComponent
541+ */
542+ public boolean getImplicitDownCycleTraversal() {
543+ return implicitDownCycleTraversal;
544+ }
545+
546+ /**
547+ * Determines whether a Component is an acceptable choice as the new
548+ * focus owner. By default, this method will accept a Component if and
549+ * only if it is visible, displayable, enabled, and focusable.
550+ *
551+ * @param aComponent the Component whose fitness as a focus owner is to
552+ * be tested
553+ * @return <code>true</code> if aComponent is visible, displayable,
554+ * enabled, and focusable; <code>false</code> otherwise
555+ */
556+ protected boolean accept(Component aComponent) {
557+ if (!aComponent.canBeFocusOwner()) {
558+ return false;
559+ }
560+
561+ // Verify that the Component is recursively enabled. Disabling a
562+ // heavyweight Container disables its children, whereas disabling
563+ // a lightweight Container does not.
564+ if (!(aComponent instanceof Window)) {
565+ for (Container enableTest = aComponent.getParent();
566+ enableTest != null;
567+ enableTest = enableTest.getParent())
568+ {
569+ if (!(enableTest.isEnabled() || enableTest.isLightweight())) {
570+ return false;
571+ }
572+ if (enableTest instanceof Window) {
573+ break;
574+ }
575+ }
576+ }
577+
578+ return true;
579+ }
580+}