1 /*
2 * Copyright 1995-2006 Sun Microsystems, Inc. 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. Sun designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
22 * CA 95054 USA or visit www.sun.com if you need additional information or
23 * have any questions.
24 */
25 package java.awt;
26
27 import java.awt.peer.MenuComponentPeer;
28 import java.awt.event.ActionEvent;
29 import java.io.IOException;
30 import java.io.ObjectInputStream;
31 import sun.awt.AppContext;
32 import sun.awt.SunToolkit;
33 import javax.accessibility;
34
35 /**
36 * The abstract class <code>MenuComponent</code> is the superclass
37 * of all menu-related components. In this respect, the class
38 * <code>MenuComponent</code> is analogous to the abstract superclass
39 * <code>Component</code> for AWT components.
40 * <p>
41 * Menu components receive and process AWT events, just as components do,
42 * through the method <code>processEvent</code>.
43 *
44 * @author Arthur van Hoff
45 * @since JDK1.0
46 */
47 public abstract class MenuComponent implements java.io.Serializable {
48
49 static {
50 /* ensure that the necessary native libraries are loaded */
51 Toolkit.loadLibraries();
52 if (!GraphicsEnvironment.isHeadless()) {
53 initIDs();
54 }
55 }
56
57 transient MenuComponentPeer peer;
58 transient MenuContainer parent;
59
60 /**
61 * The <code>AppContext</code> of the <code>MenuComponent</code>.
62 * This is set in the constructor and never changes.
63 */
64 transient AppContext appContext;
65
66 /**
67 * The menu component's font. This value can be
68 * <code>null</code> at which point a default will be used.
69 * This defaults to <code>null</code>.
70 *
71 * @serial
72 * @see #setFont(Font)
73 * @see #getFont()
74 */
75 Font font;
76
77 /**
78 * The menu component's name, which defaults to <code>null</code>.
79 * @serial
80 * @see #getName()
81 * @see #setName(String)
82 */
83 private String name;
84
85 /**
86 * A variable to indicate whether a name is explicitly set.
87 * If <code>true</code> the name will be set explicitly.
88 * This defaults to <code>false</code>.
89 * @serial
90 * @see #setName(String)
91 */
92 private boolean nameExplicitlySet = false;
93
94 /**
95 * Defaults to <code>false</code>.
96 * @serial
97 * @see #dispatchEvent(AWTEvent)
98 */
99 boolean newEventsOnly = false;
100
101 /*
102 * Internal constants for serialization.
103 */
104 final static String actionListenerK = Component.actionListenerK;
105 final static String itemListenerK = Component.itemListenerK;
106
107 /*
108 * JDK 1.1 serialVersionUID
109 */
110 private static final long serialVersionUID = -4536902356223894379L;
111
112 /**
113 * Creates a <code>MenuComponent</code>.
114 * @exception HeadlessException if
115 * <code>GraphicsEnvironment.isHeadless</code>
116 * returns <code>true</code>
117 * @see java.awt.GraphicsEnvironment#isHeadless
118 */
119 public MenuComponent() throws HeadlessException {
120 GraphicsEnvironment.checkHeadless();
121 appContext = AppContext.getAppContext();
122 }
123
124 /**
125 * Constructs a name for this <code>MenuComponent</code>.
126 * Called by <code>getName</code> when the name is <code>null</code>.
127 * @return a name for this <code>MenuComponent</code>
128 */
129 String constructComponentName() {
130 return null; // For strict compliance with prior platform versions, a MenuComponent
131 // that doesn't set its name should return null from
132 // getName()
133 }
134
135 /**
136 * Gets the name of the menu component.
137 * @return the name of the menu component
138 * @see java.awt.MenuComponent#setName(java.lang.String)
139 * @since JDK1.1
140 */
141 public String getName() {
142 if (name == null && !nameExplicitlySet) {
143 synchronized(this) {
144 if (name == null && !nameExplicitlySet)
145 name = constructComponentName();
146 }
147 }
148 return name;
149 }
150
151 /**
152 * Sets the name of the component to the specified string.
153 * @param name the name of the menu component
154 * @see java.awt.MenuComponent#getName
155 * @since JDK1.1
156 */
157 public void setName(String name) {
158 synchronized(this) {
159 this.name = name;
160 nameExplicitlySet = true;
161 }
162 }
163
164 /**
165 * Returns the parent container for this menu component.
166 * @return the menu component containing this menu component,
167 * or <code>null</code> if this menu component
168 * is the outermost component, the menu bar itself
169 */
170 public MenuContainer getParent() {
171 return getParent_NoClientCode();
172 }
173 // NOTE: This method may be called by privileged threads.
174 // This functionality is implemented in a package-private method
175 // to insure that it cannot be overridden by client subclasses.
176 // DO NOT INVOKE CLIENT CODE ON THIS THREAD!
177 final MenuContainer getParent_NoClientCode() {
178 return parent;
179 }
180
181 /**
182 * @deprecated As of JDK version 1.1,
183 * programs should not directly manipulate peers.
184 */
185 @Deprecated
186 public MenuComponentPeer getPeer() {
187 return peer;
188 }
189
190 /**
191 * Gets the font used for this menu component.
192 * @return the font used in this menu component, if there is one;
193 * <code>null</code> otherwise
194 * @see java.awt.MenuComponent#setFont
195 */
196 public Font getFont() {
197 Font font = this.font;
198 if (font != null) {
199 return font;
200 }
201 MenuContainer parent = this.parent;
202 if (parent != null) {
203 return parent.getFont();
204 }
205 return null;
206 }
207
208 // NOTE: This method may be called by privileged threads.
209 // This functionality is implemented in a package-private method
210 // to insure that it cannot be overridden by client subclasses.
211 // DO NOT INVOKE CLIENT CODE ON THIS THREAD!
212 final Font getFont_NoClientCode() {
213 Font font = this.font;
214 if (font != null) {
215 return font;
216 }
217
218 // The MenuContainer interface does not have getFont_NoClientCode()
219 // and it cannot, because it must be package-private. Because of
220 // this, we must manually cast classes that implement
221 // MenuContainer.
222 Object parent = this.parent;
223 if (parent != null) {
224 if (parent instanceof Component) {
225 font = ((Component)parent).getFont_NoClientCode();
226 } else if (parent instanceof MenuComponent) {
227 font = ((MenuComponent)parent).getFont_NoClientCode();
228 }
229 }
230 return font;
231 } // getFont_NoClientCode()
232
233
234 /**
235 * Sets the font to be used for this menu component to the specified
236 * font. This font is also used by all subcomponents of this menu
237 * component, unless those subcomponents specify a different font.
238 * <p>
239 * Some platforms may not support setting of all font attributes
240 * of a menu component; in such cases, calling <code>setFont</code>
241 * will have no effect on the unsupported font attributes of this
242 * menu component. Unless subcomponents of this menu component
243 * specify a different font, this font will be used by those
244 * subcomponents if supported by the underlying platform.
245 *
246 * @param f the font to be set
247 * @see #getFont
248 * @see Font#getAttributes
249 * @see java.awt.font.TextAttribute
250 */
251 public void setFont(Font f) {
252 font = f;
253 //Fixed 6312943: NullPointerException in method MenuComponent.setFont(Font)
254 MenuComponentPeer peer = (MenuComponentPeer)this.peer;
255 if (peer != null) {
256 peer.setFont(f);
257 }
258 }
259
260 /**
261 * Removes the menu component's peer. The peer allows us to modify the
262 * appearance of the menu component without changing the functionality of
263 * the menu component.
264 */
265 public void removeNotify() {
266 synchronized (getTreeLock()) {
267 MenuComponentPeer p = (MenuComponentPeer)this.peer;
268 if (p != null) {
269 Toolkit.getEventQueue().removeSourceEvents(this, true);
270 this.peer = null;
271 p.dispose();
272 }
273 }
274 }
275
276 /**
277 * Posts the specified event to the menu.
278 * This method is part of the Java 1.0 event system
279 * and it is maintained only for backwards compatibility.
280 * Its use is discouraged, and it may not be supported
281 * in the future.
282 * @param evt the event which is to take place
283 * @deprecated As of JDK version 1.1, replaced by {@link
284 * #dispatchEvent(AWTEvent) dispatchEvent}.
285 */
286 @Deprecated
287 public boolean postEvent(Event evt) {
288 MenuContainer parent = this.parent;
289 if (parent != null) {
290 parent.postEvent(evt);
291 }
292 return false;
293 }
294
295 /**
296 * Delivers an event to this component or one of its sub components.
297 * @param e the event
298 */
299 public final void dispatchEvent(AWTEvent e) {
300 dispatchEventImpl(e);
301 }
302
303 void dispatchEventImpl(AWTEvent e) {
304 EventQueue.setCurrentEventAndMostRecentTime(e);
305
306 Toolkit.getDefaultToolkit().notifyAWTEventListeners(e);
307
308 if (newEventsOnly ||
309 (parent != null && parent instanceof MenuComponent &&
310 ((MenuComponent)parent).newEventsOnly)) {
311 if (eventEnabled(e)) {
312 processEvent(e);
313 } else if (e instanceof ActionEvent && parent != null) {
314 e.setSource(parent);
315 ((MenuComponent)parent).dispatchEvent(e);
316 }
317
318 } else { // backward compatibility
319 Event olde = e.convertToOld();
320 if (olde != null) {
321 postEvent(olde);
322 }
323 }
324 }
325
326 // REMIND: remove when filtering is done at lower level
327 boolean eventEnabled(AWTEvent e) {
328 return false;
329 }
330 /**
331 * Processes events occurring on this menu component.
332 * <p>Note that if the event parameter is <code>null</code>
333 * the behavior is unspecified and may result in an
334 * exception.
335 *
336 * @param e the event
337 * @since JDK1.1
338 */
339 protected void processEvent(AWTEvent e) {
340 }
341
342 /**
343 * Returns a string representing the state of this
344 * <code>MenuComponent</code>. This method is intended to be used
345 * only for debugging purposes, and the content and format of the
346 * returned string may vary between implementations. The returned
347 * string may be empty but may not be <code>null</code>.
348 *
349 * @return the parameter string of this menu component
350 */
351 protected String paramString() {
352 String thisName = getName();
353 return (thisName != null? thisName : "");
354 }
355
356 /**
357 * Returns a representation of this menu component as a string.
358 * @return a string representation of this menu component
359 */
360 public String toString() {
361 return getClass().getName() + "[" + paramString() + "]";
362 }
363
364 /**
365 * Gets this component's locking object (the object that owns the thread
366 * sychronization monitor) for AWT component-tree and layout
367 * operations.
368 * @return this component's locking object
369 */
370 protected final Object getTreeLock() {
371 return Component.LOCK;
372 }
373
374 /**
375 * Reads the menu component from an object input stream.
376 *
377 * @param s the <code>ObjectInputStream</code> to read
378 * @exception HeadlessException if
379 * <code>GraphicsEnvironment.isHeadless</code> returns
380 * <code>true</code>
381 * @serial
382 * @see java.awt.GraphicsEnvironment#isHeadless
383 */
384 private void readObject(ObjectInputStream s)
385 throws ClassNotFoundException, IOException, HeadlessException
386 {
387 GraphicsEnvironment.checkHeadless();
388 s.defaultReadObject();
389
390 appContext = AppContext.getAppContext();
391 }
392
393 /**
394 * Initialize JNI field and method IDs.
395 */
396 private static native void initIDs();
397
398
399 /*
400 * --- Accessibility Support ---
401 *
402 * MenuComponent will contain all of the methods in interface Accessible,
403 * though it won't actually implement the interface - that will be up
404 * to the individual objects which extend MenuComponent.
405 */
406
407 AccessibleContext accessibleContext = null;
408
409 /**
410 * Gets the <code>AccessibleContext</code> associated with
411 * this <code>MenuComponent</code>.
412 *
413 * The method implemented by this base class returns <code>null</code>.
414 * Classes that extend <code>MenuComponent</code>
415 * should implement this method to return the
416 * <code>AccessibleContext</code> associated with the subclass.
417 *
418 * @return the <code>AccessibleContext</code> of this
419 * <code>MenuComponent</code>
420 * @since 1.3
421 */
422 public AccessibleContext getAccessibleContext() {
423 return accessibleContext;
424 }
425
426 /**
427 * Inner class of <code>MenuComponent</code> used to provide
428 * default support for accessibility. This class is not meant
429 * to be used directly by application developers, but is instead
430 * meant only to be subclassed by menu component developers.
431 * <p>
432 * The class used to obtain the accessible role for this object.
433 * @since 1.3
434 */
435 protected abstract class AccessibleAWTMenuComponent
436 extends AccessibleContext
437 implements java.io.Serializable, AccessibleComponent,
438 AccessibleSelection
439 {
440 /*
441 * JDK 1.3 serialVersionUID
442 */
443 private static final long serialVersionUID = -4269533416223798698L;
444
445 /**
446 * Although the class is abstract, this should be called by
447 * all sub-classes.
448 */
449 protected AccessibleAWTMenuComponent() {
450 }
451
452 // AccessibleContext methods
453 //
454
455 /**
456 * Gets the <code>AccessibleSelection</code> associated with this
457 * object which allows its <code>Accessible</code> children to be selected.
458 *
459 * @return <code>AccessibleSelection</code> if supported by object;
460 * else return <code>null</code>
461 * @see AccessibleSelection
462 */
463 public AccessibleSelection getAccessibleSelection() {
464 return this;
465 }
466
467 /**
468 * Gets the accessible name of this object. This should almost never
469 * return <code>java.awt.MenuComponent.getName</code>, as that
470 * generally isn't a localized name, and doesn't have meaning for the
471 * user. If the object is fundamentally a text object (e.g. a menu item), the
472 * accessible name should be the text of the object (e.g. "save").
473 * If the object has a tooltip, the tooltip text may also be an
474 * appropriate String to return.
475 *
476 * @return the localized name of the object -- can be <code>null</code>
477 * if this object does not have a name
478 * @see AccessibleContext#setAccessibleName
479 */
480 public String getAccessibleName() {
481 return accessibleName;
482 }
483
484 /**
485 * Gets the accessible description of this object. This should be
486 * a concise, localized description of what this object is - what
487 * is its meaning to the user. If the object has a tooltip, the
488 * tooltip text may be an appropriate string to return, assuming
489 * it contains a concise description of the object (instead of just
490 * the name of the object - e.g. a "Save" icon on a toolbar that
491 * had "save" as the tooltip text shouldn't return the tooltip
492 * text as the description, but something like "Saves the current
493 * text document" instead).
494 *
495 * @return the localized description of the object -- can be
496 * <code>null</code> if this object does not have a description
497 * @see AccessibleContext#setAccessibleDescription
498 */
499 public String getAccessibleDescription() {
500 return accessibleDescription;
501 }
502
503 /**
504 * Gets the role of this object.
505 *
506 * @return an instance of <code>AccessibleRole</code>
507 * describing the role of the object
508 * @see AccessibleRole
509 */
510 public AccessibleRole getAccessibleRole() {
511 return AccessibleRole.AWT_COMPONENT; // Non-specific -- overridden in subclasses
512 }
513
514 /**
515 * Gets the state of this object.
516 *
517 * @return an instance of <code>AccessibleStateSet</code>
518 * containing the current state set of the object
519 * @see AccessibleState
520 */
521 public AccessibleStateSet getAccessibleStateSet() {
522 return MenuComponent.this.getAccessibleStateSet();
523 }
524
525 /**
526 * Gets the <code>Accessible</code> parent of this object.
527 * If the parent of this object implements <code>Accessible</code>,
528 * this method should simply return <code>getParent</code>.
529 *
530 * @return the <code>Accessible</code> parent of this object -- can
531 * be <code>null</code> if this object does not have an
532 * <code>Accessible</code> parent
533 */
534 public Accessible getAccessibleParent() {
535 if (accessibleParent != null) {
536 return accessibleParent;
537 } else {
538 MenuContainer parent = MenuComponent.this.getParent();
539 if (parent instanceof Accessible) {
540 return (Accessible) parent;
541 }
542 }
543 return null;
544 }
545
546 /**
547 * Gets the index of this object in its accessible parent.
548 *
549 * @return the index of this object in its parent; -1 if this
550 * object does not have an accessible parent
551 * @see #getAccessibleParent
552 */
553 public int getAccessibleIndexInParent() {
554 return MenuComponent.this.getAccessibleIndexInParent();
555 }
556
557 /**
558 * Returns the number of accessible children in the object. If all
559 * of the children of this object implement <code>Accessible</code>,
560 * then this method should return the number of children of this object.
561 *
562 * @return the number of accessible children in the object
563 */
564 public int getAccessibleChildrenCount() {
565 return 0; // MenuComponents don't have children
566 }
567
568 /**
569 * Returns the nth <code>Accessible</code> child of the object.
570 *
571 * @param i zero-based index of child
572 * @return the nth Accessible child of the object
573 */
574 public Accessible getAccessibleChild(int i) {
575 return null; // MenuComponents don't have children
576 }
577
578 /**
579 * Returns the locale of this object.
580 *
581 * @return the locale of this object
582 */
583 public java.util.Locale getLocale() {
584 MenuContainer parent = MenuComponent.this.getParent();
585 if (parent instanceof Component)
586 return ((Component)parent).getLocale();
587 else
588 return java.util.Locale.getDefault();
589 }
590
591 /**
592 * Gets the <code>AccessibleComponent</code> associated with
593 * this object if one exists. Otherwise return <code>null</code>.
594 *
595 * @return the component
596 */
597 public AccessibleComponent getAccessibleComponent() {
598 return this;
599 }
600
601
602 // AccessibleComponent methods
603 //
604 /**
605 * Gets the background color of this object.
606 *
607 * @return the background color, if supported, of the object;
608 * otherwise, <code>null</code>
609 */
610 public Color getBackground() {
611 return null; // Not supported for MenuComponents
612 }
613
614 /**
615 * Sets the background color of this object.
616 * (For transparency, see <code>isOpaque</code>.)
617 *
618 * @param c the new <code>Color</code> for the background
619 * @see Component#isOpaque
620 */
621 public void setBackground(Color c) {
622 // Not supported for MenuComponents
623 }
624
625 /**
626 * Gets the foreground color of this object.
627 *
628 * @return the foreground color, if supported, of the object;
629 * otherwise, <code>null</code>
630 */
631 public Color getForeground() {
632 return null; // Not supported for MenuComponents
633 }
634
635 /**
636 * Sets the foreground color of this object.
637 *
638 * @param c the new <code>Color</code> for the foreground
639 */
640 public void setForeground(Color c) {
641 // Not supported for MenuComponents
642 }
643
644 /**
645 * Gets the <code>Cursor</code> of this object.
646 *
647 * @return the <code>Curso</code>, if supported, of the object;
648 * otherwise, <code>null</code>
649 */
650 public Cursor getCursor() {
651 return null; // Not supported for MenuComponents
652 }
653
654 /**
655 * Sets the <code>Cursor</code> of this object.
656 * <p>
657 * The method may have no visual effect if the Java platform
658 * implementation and/or the native system do not support
659 * changing the mouse cursor shape.
660 * @param cursor the new <code>Cursor</code> for the object
661 */
662 public void setCursor(Cursor cursor) {
663 // Not supported for MenuComponents
664 }
665
666 /**
667 * Gets the <code>Font</code> of this object.
668 *
669 * @return the <code>Font</code>,if supported, for the object;
670 * otherwise, <code>null</code>
671 */
672 public Font getFont() {
673 return MenuComponent.this.getFont();
674 }
675
676 /**
677 * Sets the <code>Font</code> of this object.
678 *
679 * @param f the new <code>Font</code> for the object
680 */
681 public void setFont(Font f) {
682 MenuComponent.this.setFont(f);
683 }
684
685 /**
686 * Gets the <code>FontMetrics</code> of this object.
687 *
688 * @param f the <code>Font</code>
689 * @return the FontMetrics, if supported, the object;
690 * otherwise, <code>null</code>
691 * @see #getFont
692 */
693 public FontMetrics getFontMetrics(Font f) {
694 return null; // Not supported for MenuComponents
695 }
696
697 /**
698 * Determines if the object is enabled.
699 *
700 * @return true if object is enabled; otherwise, false
701 */
702 public boolean isEnabled() {
703 return true; // Not supported for MenuComponents
704 }
705
706 /**
707 * Sets the enabled state of the object.
708 *
709 * @param b if true, enables this object; otherwise, disables it
710 */
711 public void setEnabled(boolean b) {
712 // Not supported for MenuComponents
713 }
714
715 /**
716 * Determines if the object is visible. Note: this means that the
717 * object intends to be visible; however, it may not in fact be
718 * showing on the screen because one of the objects that this object
719 * is contained by is not visible. To determine if an object is
720 * showing on the screen, use <code>isShowing</code>.
721 *
722 * @return true if object is visible; otherwise, false
723 */
724 public boolean isVisible() {
725 return true; // Not supported for MenuComponents
726 }
727
728 /**
729 * Sets the visible state of the object.
730 *
731 * @param b if true, shows this object; otherwise, hides it
732 */
733 public void setVisible(boolean b) {
734 // Not supported for MenuComponents
735 }
736
737 /**
738 * Determines if the object is showing. This is determined by checking
739 * the visibility of the object and ancestors of the object. Note:
740 * this will return true even if the object is obscured by another
741 * (for example, it happens to be underneath a menu that was pulled
742 * down).
743 *
744 * @return true if object is showing; otherwise, false
745 */
746 public boolean isShowing() {
747 return true; // Not supported for MenuComponents
748 }
749
750 /**
751 * Checks whether the specified point is within this object's bounds,
752 * where the point's x and y coordinates are defined to be relative to
753 * the coordinate system of the object.
754 *
755 * @param p the <code>Point</code> relative to the coordinate
756 * system of the object
757 * @return true if object contains <code>Point</code>; otherwise false
758 */
759 public boolean contains(Point p) {
760 return false; // Not supported for MenuComponents
761 }
762
763 /**
764 * Returns the location of the object on the screen.
765 *
766 * @return location of object on screen -- can be <code>null</code>
767 * if this object is not on the screen
768 */
769 public Point getLocationOnScreen() {
770 return null; // Not supported for MenuComponents
771 }
772
773 /**
774 * Gets the location of the object relative to the parent in the form
775 * of a point specifying the object's top-left corner in the screen's
776 * coordinate space.
777 *
778 * @return an instance of <code>Point</code> representing the
779 * top-left corner of the object's bounds in the coordinate
780 * space of the screen; <code>null</code> if
781 * this object or its parent are not on the screen
782 */
783 public Point getLocation() {
784 return null; // Not supported for MenuComponents
785 }
786
787 /**
788 * Sets the location of the object relative to the parent.
789 */
790 public void setLocation(Point p) {
791 // Not supported for MenuComponents
792 }
793
794 /**
795 * Gets the bounds of this object in the form of a
796 * <code>Rectangle</code> object.
797 * The bounds specify this object's width, height, and location
798 * relative to its parent.
799 *
800 * @return a rectangle indicating this component's bounds;
801 * <code>null</code> if this object is not on the screen
802 */
803 public Rectangle getBounds() {
804 return null; // Not supported for MenuComponents
805 }
806
807 /**
808 * Sets the bounds of this object in the form of a
809 * <code>Rectangle</code> object.
810 * The bounds specify this object's width, height, and location
811 * relative to its parent.
812 *
813 * @param r a rectangle indicating this component's bounds
814 */
815 public void setBounds(Rectangle r) {
816 // Not supported for MenuComponents
817 }
818
819 /**
820 * Returns the size of this object in the form of a
821 * <code>Dimension</code> object. The height field of
822 * the <code>Dimension</code> object contains this object's
823 * height, and the width field of the <code>Dimension</code>
824 * object contains this object's width.
825 *
826 * @return a <code>Dimension</code> object that indicates the
827 * size of this component; <code>null</code>
828 * if this object is not on the screen
829 */
830 public Dimension getSize() {
831 return null; // Not supported for MenuComponents
832 }
833
834 /**
835 * Resizes this object.
836 *
837 * @param d - the <code>Dimension</code> specifying the
838 * new size of the object
839 */
840 public void setSize(Dimension d) {
841 // Not supported for MenuComponents
842 }
843
844 /**
845 * Returns the <code>Accessible</code> child, if one exists,
846 * contained at the local coordinate <code>Point</code>.
847 * If there is no <code>Accessible</code> child, <code>null</code>
848 * is returned.
849 *
850 * @param p the point defining the top-left corner of the
851 * <code>Accessible</code>, given in the coordinate space
852 * of the object's parent
853 * @return the <code>Accessible</code>, if it exists,
854 * at the specified location; else <code>null</code>
855 */
856 public Accessible getAccessibleAt(Point p) {
857 return null; // MenuComponents don't have children
858 }
859
860 /**
861 * Returns whether this object can accept focus or not.
862 *
863 * @return true if object can accept focus; otherwise false
864 */
865 public boolean isFocusTraversable() {
866 return true; // Not supported for MenuComponents
867 }
868
869 /**
870 * Requests focus for this object.
871 */
872 public void requestFocus() {
873 // Not supported for MenuComponents
874 }
875
876 /**
877 * Adds the specified focus listener to receive focus events from this
878 * component.
879 *
880 * @param l the focus listener
881 */
882 public void addFocusListener(java.awt.event.FocusListener l) {
883 // Not supported for MenuComponents
884 }
885
886 /**
887 * Removes the specified focus listener so it no longer receives focus
888 * events from this component.
889 *
890 * @param l the focus listener
891 */
892 public void removeFocusListener(java.awt.event.FocusListener l) {
893 // Not supported for MenuComponents
894 }
895
896 // AccessibleSelection methods
897 //
898
899 /**
900 * Returns the number of <code>Accessible</code> children currently selected.
901 * If no children are selected, the return value will be 0.
902 *
903 * @return the number of items currently selected
904 */
905 public int getAccessibleSelectionCount() {
906 return 0; // To be fully implemented in a future release
907 }
908
909 /**
910 * Returns an <code>Accessible</code> representing the specified
911 * selected child in the object. If there isn't a selection, or there are
912 * fewer children selected than the integer passed in, the return
913 * value will be <code>null</code>.
914 * <p>Note that the index represents the i-th selected child, which
915 * is different from the i-th child.
916 *
917 * @param i the zero-based index of selected children
918 * @return the i-th selected child
919 * @see #getAccessibleSelectionCount
920 */
921 public Accessible getAccessibleSelection(int i) {
922 return null; // To be fully implemented in a future release
923 }
924
925 /**
926 * Determines if the current child of this object is selected.
927 *
928 * @return true if the current child of this object is selected;
929 * else false
930 * @param i the zero-based index of the child in this
931 * <code>Accessible</code> object
932 * @see AccessibleContext#getAccessibleChild
933 */
934 public boolean isAccessibleChildSelected(int i) {
935 return false; // To be fully implemented in a future release
936 }
937
938 /**
939 * Adds the specified <code>Accessible</code> child of the object
940 * to the object's selection. If the object supports multiple selections,
941 * the specified child is added to any existing selection, otherwise
942 * it replaces any existing selection in the object. If the
943 * specified child is already selected, this method has no effect.
944 *
945 * @param i the zero-based index of the child
946 * @see AccessibleContext#getAccessibleChild
947 */
948 public void addAccessibleSelection(int i) {
949 // To be fully implemented in a future release
950 }
951
952 /**
953 * Removes the specified child of the object from the object's
954 * selection. If the specified item isn't currently selected, this
955 * method has no effect.
956 *
957 * @param i the zero-based index of the child
958 * @see AccessibleContext#getAccessibleChild
959 */
960 public void removeAccessibleSelection(int i) {
961 // To be fully implemented in a future release
962 }
963
964 /**
965 * Clears the selection in the object, so that no children in the
966 * object are selected.
967 */
968 public void clearAccessibleSelection() {
969 // To be fully implemented in a future release
970 }
971
972 /**
973 * Causes every child of the object to be selected
974 * if the object supports multiple selections.
975 */
976 public void selectAllAccessibleSelection() {
977 // To be fully implemented in a future release
978 }
979
980 } // inner class AccessibleAWTComponent
981
982 /**
983 * Gets the index of this object in its accessible parent.
984 *
985 * @return -1 if this object does not have an accessible parent;
986 * otherwise, the index of the child in its accessible parent.
987 */
988 int getAccessibleIndexInParent() {
989 MenuContainer localParent = parent;
990 if (!(localParent instanceof MenuComponent)) {
991 // MenuComponents only have accessible index when inside MenuComponents
992 return -1;
993 }
994 MenuComponent localParentMenu = (MenuComponent)localParent;
995 return localParentMenu.getAccessibleChildIndex(this);
996 }
997
998 /**
999 * Gets the index of the child within this MenuComponent.
1000 *
1001 * @param child MenuComponent whose index we are interested in.
1002 * @return -1 if this object doesn't contain the child,
1003 * otherwise, index of the child.
1004 */
1005 int getAccessibleChildIndex(MenuComponent child) {
1006 return -1; // Overridden in subclasses.
1007 }
1008
1009 /**
1010 * Gets the state of this object.
1011 *
1012 * @return an instance of <code>AccessibleStateSet</code>
1013 * containing the current state set of the object
1014 * @see AccessibleState
1015 */
1016 AccessibleStateSet getAccessibleStateSet() {
1017 AccessibleStateSet states = new AccessibleStateSet();
1018 return states;
1019 }
1020
1021 }
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