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   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 sun.awt.AWTAccessor;
   34   import javax.accessibility;
   35   
   36   import java.security.AccessControlContext;
   37   import java.security.AccessController;
   38   
   39   /**
   40    * The abstract class <code>MenuComponent</code> is the superclass
   41    * of all menu-related components. In this respect, the class
   42    * <code>MenuComponent</code> is analogous to the abstract superclass
   43    * <code>Component</code> for AWT components.
   44    * <p>
   45    * Menu components receive and process AWT events, just as components do,
   46    * through the method <code>processEvent</code>.
   47    *
   48    * @author      Arthur van Hoff
   49    * @since       JDK1.0
   50    */
   51   public abstract class MenuComponent implements java.io.Serializable {
   52   
   53       static {
   54           /* ensure that the necessary native libraries are loaded */
   55           Toolkit.loadLibraries();
   56           if (!GraphicsEnvironment.isHeadless()) {
   57               initIDs();
   58           }
   59       }
   60   
   61       transient MenuComponentPeer peer;
   62       transient MenuContainer parent;
   63   
   64       /**
   65        * The <code>AppContext</code> of the <code>MenuComponent</code>.
   66        * This is set in the constructor and never changes.
   67        */
   68       transient AppContext appContext;
   69   
   70       /**
   71        * The menu component's font. This value can be
   72        * <code>null</code> at which point a default will be used.
   73        * This defaults to <code>null</code>.
   74        *
   75        * @serial
   76        * @see #setFont(Font)
   77        * @see #getFont()
   78        */
   79       Font font;
   80   
   81       /**
   82        * The menu component's name, which defaults to <code>null</code>.
   83        * @serial
   84        * @see #getName()
   85        * @see #setName(String)
   86        */
   87       private String name;
   88   
   89       /**
   90        * A variable to indicate whether a name is explicitly set.
   91        * If <code>true</code> the name will be set explicitly.
   92        * This defaults to <code>false</code>.
   93        * @serial
   94        * @see #setName(String)
   95        */
   96       private boolean nameExplicitlySet = false;
   97   
   98       /**
   99        * Defaults to <code>false</code>.
  100        * @serial
  101        * @see #dispatchEvent(AWTEvent)
  102        */
  103       boolean newEventsOnly = false;
  104   
  105       /*
  106        * The menu's AccessControlContext.
  107        */
  108       private transient volatile AccessControlContext acc =
  109               AccessController.getContext();
  110   
  111       /*
  112        * Returns the acc this menu component was constructed with.
  113        */
  114       final AccessControlContext getAccessControlContext() {
  115           if (acc == null) {
  116               throw new SecurityException(
  117                       "MenuComponent is missing AccessControlContext");
  118           }
  119           return acc;
  120       }
  121   
  122       /*
  123        * Internal constants for serialization.
  124        */
  125       final static String actionListenerK = Component.actionListenerK;
  126       final static String itemListenerK = Component.itemListenerK;
  127   
  128       /*
  129        * JDK 1.1 serialVersionUID
  130        */
  131       private static final long serialVersionUID = -4536902356223894379L;
  132   
  133       static {
  134           AWTAccessor.setMenuComponentAccessor(
  135               new AWTAccessor.MenuComponentAccessor() {
  136                   public AppContext getAppContext(MenuComponent menuComp) {
  137                       return menuComp.appContext;
  138                   }
  139                   public void setAppContext(MenuComponent menuComp,
  140                                             AppContext appContext) {
  141                       menuComp.appContext = appContext;
  142                   }
  143                   public MenuContainer getParent(MenuComponent menuComp) {
  144                       return menuComp.parent;
  145                   }
  146               });
  147       }
  148   
  149       /**
  150        * Creates a <code>MenuComponent</code>.
  151        * @exception HeadlessException if
  152        *    <code>GraphicsEnvironment.isHeadless</code>
  153        *    returns <code>true</code>
  154        * @see java.awt.GraphicsEnvironment#isHeadless
  155        */
  156       public MenuComponent() throws HeadlessException {
  157           GraphicsEnvironment.checkHeadless();
  158           appContext = AppContext.getAppContext();
  159       }
  160   
  161       /**
  162        * Constructs a name for this <code>MenuComponent</code>.
  163        * Called by <code>getName</code> when the name is <code>null</code>.
  164        * @return a name for this <code>MenuComponent</code>
  165        */
  166       String constructComponentName() {
  167           return null; // For strict compliance with prior platform versions, a MenuComponent
  168                        // that doesn't set its name should return null from
  169                        // getName()
  170       }
  171   
  172       /**
  173        * Gets the name of the menu component.
  174        * @return        the name of the menu component
  175        * @see           java.awt.MenuComponent#setName(java.lang.String)
  176        * @since         JDK1.1
  177        */
  178       public String getName() {
  179           if (name == null && !nameExplicitlySet) {
  180               synchronized(this) {
  181                   if (name == null && !nameExplicitlySet)
  182                       name = constructComponentName();
  183               }
  184           }
  185           return name;
  186       }
  187   
  188       /**
  189        * Sets the name of the component to the specified string.
  190        * @param         name    the name of the menu component
  191        * @see           java.awt.MenuComponent#getName
  192        * @since         JDK1.1
  193        */
  194       public void setName(String name) {
  195           synchronized(this) {
  196               this.name = name;
  197               nameExplicitlySet = true;
  198           }
  199       }
  200   
  201       /**
  202        * Returns the parent container for this menu component.
  203        * @return    the menu component containing this menu component,
  204        *                 or <code>null</code> if this menu component
  205        *                 is the outermost component, the menu bar itself
  206        */
  207       public MenuContainer getParent() {
  208           return getParent_NoClientCode();
  209       }
  210       // NOTE: This method may be called by privileged threads.
  211       //       This functionality is implemented in a package-private method
  212       //       to insure that it cannot be overridden by client subclasses.
  213       //       DO NOT INVOKE CLIENT CODE ON THIS THREAD!
  214       final MenuContainer getParent_NoClientCode() {
  215           return parent;
  216       }
  217   
  218       /**
  219        * @deprecated As of JDK version 1.1,
  220        * programs should not directly manipulate peers.
  221        */
  222       @Deprecated
  223       public MenuComponentPeer getPeer() {
  224           return peer;
  225       }
  226   
  227       /**
  228        * Gets the font used for this menu component.
  229        * @return   the font used in this menu component, if there is one;
  230        *                  <code>null</code> otherwise
  231        * @see     java.awt.MenuComponent#setFont
  232        */
  233       public Font getFont() {
  234           Font font = this.font;
  235           if (font != null) {
  236               return font;
  237           }
  238           MenuContainer parent = this.parent;
  239           if (parent != null) {
  240               return parent.getFont();
  241           }
  242           return null;
  243       }
  244   
  245       // NOTE: This method may be called by privileged threads.
  246       //       This functionality is implemented in a package-private method
  247       //       to insure that it cannot be overridden by client subclasses.
  248       //       DO NOT INVOKE CLIENT CODE ON THIS THREAD!
  249       final Font getFont_NoClientCode() {
  250           Font font = this.font;
  251           if (font != null) {
  252               return font;
  253           }
  254   
  255           // The MenuContainer interface does not have getFont_NoClientCode()
  256           // and it cannot, because it must be package-private. Because of
  257           // this, we must manually cast classes that implement
  258           // MenuContainer.
  259           Object parent = this.parent;
  260           if (parent != null) {
  261               if (parent instanceof Component) {
  262                   font = ((Component)parent).getFont_NoClientCode();
  263               } else if (parent instanceof MenuComponent) {
  264                   font = ((MenuComponent)parent).getFont_NoClientCode();
  265               }
  266           }
  267           return font;
  268       } // getFont_NoClientCode()
  269   
  270   
  271       /**
  272        * Sets the font to be used for this menu component to the specified
  273        * font. This font is also used by all subcomponents of this menu
  274        * component, unless those subcomponents specify a different font.
  275        * <p>
  276        * Some platforms may not support setting of all font attributes
  277        * of a menu component; in such cases, calling <code>setFont</code>
  278        * will have no effect on the unsupported font attributes of this
  279        * menu component.  Unless subcomponents of this menu component
  280        * specify a different font, this font will be used by those
  281        * subcomponents if supported by the underlying platform.
  282        *
  283        * @param     f   the font to be set
  284        * @see       #getFont
  285        * @see       Font#getAttributes
  286        * @see       java.awt.font.TextAttribute
  287        */
  288       public void setFont(Font f) {
  289           font = f;
  290           //Fixed 6312943: NullPointerException in method MenuComponent.setFont(Font)
  291           MenuComponentPeer peer = (MenuComponentPeer)this.peer;
  292           if (peer != null) {
  293               peer.setFont(f);
  294           }
  295       }
  296   
  297       /**
  298        * Removes the menu component's peer.  The peer allows us to modify the
  299        * appearance of the menu component without changing the functionality of
  300        * the menu component.
  301        */
  302       public void removeNotify() {
  303           synchronized (getTreeLock()) {
  304               MenuComponentPeer p = (MenuComponentPeer)this.peer;
  305               if (p != null) {
  306                   Toolkit.getEventQueue().removeSourceEvents(this, true);
  307                   this.peer = null;
  308                   p.dispose();
  309               }
  310           }
  311       }
  312   
  313       /**
  314        * Posts the specified event to the menu.
  315        * This method is part of the Java&nbsp;1.0 event system
  316        * and it is maintained only for backwards compatibility.
  317        * Its use is discouraged, and it may not be supported
  318        * in the future.
  319        * @param evt the event which is to take place
  320        * @deprecated As of JDK version 1.1, replaced by {@link
  321        * #dispatchEvent(AWTEvent) dispatchEvent}.
  322        */
  323       @Deprecated
  324       public boolean postEvent(Event evt) {
  325           MenuContainer parent = this.parent;
  326           if (parent != null) {
  327               parent.postEvent(evt);
  328           }
  329           return false;
  330       }
  331   
  332       /**
  333        * Delivers an event to this component or one of its sub components.
  334        * @param e the event
  335        */
  336       public final void dispatchEvent(AWTEvent e) {
  337           dispatchEventImpl(e);
  338       }
  339   
  340       void dispatchEventImpl(AWTEvent e) {
  341           EventQueue.setCurrentEventAndMostRecentTime(e);
  342   
  343           Toolkit.getDefaultToolkit().notifyAWTEventListeners(e);
  344   
  345           if (newEventsOnly ||
  346               (parent != null && parent instanceof MenuComponent &&
  347                ((MenuComponent)parent).newEventsOnly)) {
  348               if (eventEnabled(e)) {
  349                   processEvent(e);
  350               } else if (e instanceof ActionEvent && parent != null) {
  351                   e.setSource(parent);
  352                   ((MenuComponent)parent).dispatchEvent(e);
  353               }
  354   
  355           } else { // backward compatibility
  356               Event olde = e.convertToOld();
  357               if (olde != null) {
  358                   postEvent(olde);
  359               }
  360           }
  361       }
  362   
  363       // REMIND: remove when filtering is done at lower level
  364       boolean eventEnabled(AWTEvent e) {
  365           return false;
  366       }
  367       /**
  368        * Processes events occurring on this menu component.
  369        * <p>Note that if the event parameter is <code>null</code>
  370        * the behavior is unspecified and may result in an
  371        * exception.
  372        *
  373        * @param e the event
  374        * @since JDK1.1
  375        */
  376       protected void processEvent(AWTEvent e) {
  377       }
  378   
  379       /**
  380        * Returns a string representing the state of this
  381        * <code>MenuComponent</code>. This method is intended to be used
  382        * only for debugging purposes, and the content and format of the
  383        * returned string may vary between implementations. The returned
  384        * string may be empty but may not be <code>null</code>.
  385        *
  386        * @return     the parameter string of this menu component
  387        */
  388       protected String paramString() {
  389           String thisName = getName();
  390           return (thisName != null? thisName : "");
  391       }
  392   
  393       /**
  394        * Returns a representation of this menu component as a string.
  395        * @return  a string representation of this menu component
  396        */
  397       public String toString() {
  398           return getClass().getName() + "[" + paramString() + "]";
  399       }
  400   
  401       /**
  402        * Gets this component's locking object (the object that owns the thread
  403        * sychronization monitor) for AWT component-tree and layout
  404        * operations.
  405        * @return this component's locking object
  406        */
  407       protected final Object getTreeLock() {
  408           return Component.LOCK;
  409       }
  410   
  411       /**
  412        * Reads the menu component from an object input stream.
  413        *
  414        * @param s the <code>ObjectInputStream</code> to read
  415        * @exception HeadlessException if
  416        *   <code>GraphicsEnvironment.isHeadless</code> returns
  417        *   <code>true</code>
  418        * @serial
  419        * @see java.awt.GraphicsEnvironment#isHeadless
  420        */
  421       private void readObject(ObjectInputStream s)
  422           throws ClassNotFoundException, IOException, HeadlessException
  423       {
  424           GraphicsEnvironment.checkHeadless();
  425   
  426           acc = AccessController.getContext();
  427   
  428           s.defaultReadObject();
  429   
  430           appContext = AppContext.getAppContext();
  431       }
  432   
  433       /**
  434        * Initialize JNI field and method IDs.
  435        */
  436       private static native void initIDs();
  437   
  438   
  439       /*
  440        * --- Accessibility Support ---
  441        *
  442        *  MenuComponent will contain all of the methods in interface Accessible,
  443        *  though it won't actually implement the interface - that will be up
  444        *  to the individual objects which extend MenuComponent.
  445        */
  446   
  447       AccessibleContext accessibleContext = null;
  448   
  449       /**
  450        * Gets the <code>AccessibleContext</code> associated with
  451        * this <code>MenuComponent</code>.
  452        *
  453        * The method implemented by this base class returns <code>null</code>.
  454        * Classes that extend <code>MenuComponent</code>
  455        * should implement this method to return the
  456        * <code>AccessibleContext</code> associated with the subclass.
  457        *
  458        * @return the <code>AccessibleContext</code> of this
  459        *     <code>MenuComponent</code>
  460        * @since 1.3
  461        */
  462       public AccessibleContext getAccessibleContext() {
  463           return accessibleContext;
  464       }
  465   
  466       /**
  467        * Inner class of <code>MenuComponent</code> used to provide
  468        * default support for accessibility.  This class is not meant
  469        * to be used directly by application developers, but is instead
  470        * meant only to be subclassed by menu component developers.
  471        * <p>
  472        * The class used to obtain the accessible role for this object.
  473        * @since 1.3
  474        */
  475       protected abstract class AccessibleAWTMenuComponent
  476           extends AccessibleContext
  477           implements java.io.Serializable, AccessibleComponent,
  478                      AccessibleSelection
  479       {
  480           /*
  481            * JDK 1.3 serialVersionUID
  482            */
  483           private static final long serialVersionUID = -4269533416223798698L;
  484   
  485           /**
  486            * Although the class is abstract, this should be called by
  487            * all sub-classes.
  488            */
  489           protected AccessibleAWTMenuComponent() {
  490           }
  491   
  492           // AccessibleContext methods
  493           //
  494   
  495           /**
  496            * Gets the <code>AccessibleSelection</code> associated with this
  497            * object which allows its <code>Accessible</code> children to be selected.
  498            *
  499            * @return <code>AccessibleSelection</code> if supported by object;
  500            *      else return <code>null</code>
  501            * @see AccessibleSelection
  502            */
  503           public AccessibleSelection getAccessibleSelection() {
  504               return this;
  505           }
  506   
  507           /**
  508            * Gets the accessible name of this object.  This should almost never
  509            * return <code>java.awt.MenuComponent.getName</code>, as that
  510            * generally isn't a localized name, and doesn't have meaning for the
  511            * user.  If the object is fundamentally a text object (e.g. a menu item), the
  512            * accessible name should be the text of the object (e.g. "save").
  513            * If the object has a tooltip, the tooltip text may also be an
  514            * appropriate String to return.
  515            *
  516            * @return the localized name of the object -- can be <code>null</code>
  517            *         if this object does not have a name
  518            * @see AccessibleContext#setAccessibleName
  519            */
  520           public String getAccessibleName() {
  521               return accessibleName;
  522           }
  523   
  524           /**
  525            * Gets the accessible description of this object.  This should be
  526            * a concise, localized description of what this object is - what
  527            * is its meaning to the user.  If the object has a tooltip, the
  528            * tooltip text may be an appropriate string to return, assuming
  529            * it contains a concise description of the object (instead of just
  530            * the name of the object - e.g. a "Save" icon on a toolbar that
  531            * had "save" as the tooltip text shouldn't return the tooltip
  532            * text as the description, but something like "Saves the current
  533            * text document" instead).
  534            *
  535            * @return the localized description of the object -- can be
  536            *     <code>null</code> if this object does not have a description
  537            * @see AccessibleContext#setAccessibleDescription
  538            */
  539           public String getAccessibleDescription() {
  540               return accessibleDescription;
  541           }
  542   
  543           /**
  544            * Gets the role of this object.
  545            *
  546            * @return an instance of <code>AccessibleRole</code>
  547            *     describing the role of the object
  548            * @see AccessibleRole
  549            */
  550           public AccessibleRole getAccessibleRole() {
  551               return AccessibleRole.AWT_COMPONENT; // Non-specific -- overridden in subclasses
  552           }
  553   
  554           /**
  555            * Gets the state of this object.
  556            *
  557            * @return an instance of <code>AccessibleStateSet</code>
  558            *     containing the current state set of the object
  559            * @see AccessibleState
  560            */
  561           public AccessibleStateSet getAccessibleStateSet() {
  562               return MenuComponent.this.getAccessibleStateSet();
  563           }
  564   
  565           /**
  566            * Gets the <code>Accessible</code> parent of this object.
  567            * If the parent of this object implements <code>Accessible</code>,
  568            * this method should simply return <code>getParent</code>.
  569            *
  570            * @return the <code>Accessible</code> parent of this object -- can
  571            *    be <code>null</code> if this object does not have an
  572            *    <code>Accessible</code> parent
  573            */
  574           public Accessible getAccessibleParent() {
  575               if (accessibleParent != null) {
  576                   return accessibleParent;
  577               } else {
  578                   MenuContainer parent = MenuComponent.this.getParent();
  579                   if (parent instanceof Accessible) {
  580                       return (Accessible) parent;
  581                   }
  582               }
  583               return null;
  584           }
  585   
  586           /**
  587            * Gets the index of this object in its accessible parent.
  588            *
  589            * @return the index of this object in its parent; -1 if this
  590            *     object does not have an accessible parent
  591            * @see #getAccessibleParent
  592            */
  593           public int getAccessibleIndexInParent() {
  594               return MenuComponent.this.getAccessibleIndexInParent();
  595           }
  596   
  597           /**
  598            * Returns the number of accessible children in the object.  If all
  599            * of the children of this object implement <code>Accessible</code>,
  600            * then this method should return the number of children of this object.
  601            *
  602            * @return the number of accessible children in the object
  603            */
  604           public int getAccessibleChildrenCount() {
  605               return 0; // MenuComponents don't have children
  606           }
  607   
  608           /**
  609            * Returns the nth <code>Accessible</code> child of the object.
  610            *
  611            * @param i zero-based index of child
  612            * @return the nth Accessible child of the object
  613            */
  614           public Accessible getAccessibleChild(int i) {
  615               return null; // MenuComponents don't have children
  616           }
  617   
  618           /**
  619            * Returns the locale of this object.
  620            *
  621            * @return the locale of this object
  622            */
  623           public java.util.Locale getLocale() {
  624               MenuContainer parent = MenuComponent.this.getParent();
  625               if (parent instanceof Component)
  626                   return ((Component)parent).getLocale();
  627               else
  628                   return java.util.Locale.getDefault();
  629           }
  630   
  631           /**
  632            * Gets the <code>AccessibleComponent</code> associated with
  633            * this object if one exists.  Otherwise return <code>null</code>.
  634            *
  635            * @return the component
  636            */
  637           public AccessibleComponent getAccessibleComponent() {
  638               return this;
  639           }
  640   
  641   
  642           // AccessibleComponent methods
  643           //
  644           /**
  645            * Gets the background color of this object.
  646            *
  647            * @return the background color, if supported, of the object;
  648            *     otherwise, <code>null</code>
  649            */
  650           public Color getBackground() {
  651               return null; // Not supported for MenuComponents
  652           }
  653   
  654           /**
  655            * Sets the background color of this object.
  656            * (For transparency, see <code>isOpaque</code>.)
  657            *
  658            * @param c the new <code>Color</code> for the background
  659            * @see Component#isOpaque
  660            */
  661           public void setBackground(Color c) {
  662               // Not supported for MenuComponents
  663           }
  664   
  665           /**
  666            * Gets the foreground color of this object.
  667            *
  668            * @return the foreground color, if supported, of the object;
  669            *     otherwise, <code>null</code>
  670            */
  671           public Color getForeground() {
  672               return null; // Not supported for MenuComponents
  673           }
  674   
  675           /**
  676            * Sets the foreground color of this object.
  677            *
  678            * @param c the new <code>Color</code> for the foreground
  679            */
  680           public void setForeground(Color c) {
  681               // Not supported for MenuComponents
  682           }
  683   
  684           /**
  685            * Gets the <code>Cursor</code> of this object.
  686            *
  687            * @return the <code>Curso</code>, if supported, of the object;
  688            *     otherwise, <code>null</code>
  689            */
  690           public Cursor getCursor() {
  691               return null; // Not supported for MenuComponents
  692           }
  693   
  694           /**
  695            * Sets the <code>Cursor</code> of this object.
  696            * <p>
  697            * The method may have no visual effect if the Java platform
  698            * implementation and/or the native system do not support
  699            * changing the mouse cursor shape.
  700            * @param cursor the new <code>Cursor</code> for the object
  701            */
  702           public void setCursor(Cursor cursor) {
  703               // Not supported for MenuComponents
  704           }
  705   
  706           /**
  707            * Gets the <code>Font</code> of this object.
  708            *
  709            * @return the <code>Font</code>,if supported, for the object;
  710            *     otherwise, <code>null</code>
  711            */
  712           public Font getFont() {
  713               return MenuComponent.this.getFont();
  714           }
  715   
  716           /**
  717            * Sets the <code>Font</code> of this object.
  718            *
  719            * @param f the new <code>Font</code> for the object
  720            */
  721           public void setFont(Font f) {
  722               MenuComponent.this.setFont(f);
  723           }
  724   
  725           /**
  726            * Gets the <code>FontMetrics</code> of this object.
  727            *
  728            * @param f the <code>Font</code>
  729            * @return the FontMetrics, if supported, the object;
  730            *              otherwise, <code>null</code>
  731            * @see #getFont
  732            */
  733           public FontMetrics getFontMetrics(Font f) {
  734               return null; // Not supported for MenuComponents
  735           }
  736   
  737           /**
  738            * Determines if the object is enabled.
  739            *
  740            * @return true if object is enabled; otherwise, false
  741            */
  742           public boolean isEnabled() {
  743               return true; // Not supported for MenuComponents
  744           }
  745   
  746           /**
  747            * Sets the enabled state of the object.
  748            *
  749            * @param b if true, enables this object; otherwise, disables it
  750            */
  751           public void setEnabled(boolean b) {
  752               // Not supported for MenuComponents
  753           }
  754   
  755           /**
  756            * Determines if the object is visible.  Note: this means that the
  757            * object intends to be visible; however, it may not in fact be
  758            * showing on the screen because one of the objects that this object
  759            * is contained by is not visible.  To determine if an object is
  760            * showing on the screen, use <code>isShowing</code>.
  761            *
  762            * @return true if object is visible; otherwise, false
  763            */
  764           public boolean isVisible() {
  765               return true; // Not supported for MenuComponents
  766           }
  767   
  768           /**
  769            * Sets the visible state of the object.
  770            *
  771            * @param b if true, shows this object; otherwise, hides it
  772            */
  773           public void setVisible(boolean b) {
  774               // Not supported for MenuComponents
  775           }
  776   
  777           /**
  778            * Determines if the object is showing.  This is determined by checking
  779            * the visibility of the object and ancestors of the object.  Note:
  780            * this will return true even if the object is obscured by another
  781            * (for example, it happens to be underneath a menu that was pulled
  782            * down).
  783            *
  784            * @return true if object is showing; otherwise, false
  785            */
  786           public boolean isShowing() {
  787               return true; // Not supported for MenuComponents
  788           }
  789   
  790           /**
  791            * Checks whether the specified point is within this object's bounds,
  792            * where the point's x and y coordinates are defined to be relative to
  793            * the coordinate system of the object.
  794            *
  795            * @param p the <code>Point</code> relative to the coordinate
  796            *     system of the object
  797            * @return true if object contains <code>Point</code>; otherwise false
  798            */
  799           public boolean contains(Point p) {
  800               return false; // Not supported for MenuComponents
  801           }
  802   
  803           /**
  804            * Returns the location of the object on the screen.
  805            *
  806            * @return location of object on screen -- can be <code>null</code>
  807            *     if this object is not on the screen
  808            */
  809           public Point getLocationOnScreen() {
  810               return null; // Not supported for MenuComponents
  811           }
  812   
  813           /**
  814            * Gets the location of the object relative to the parent in the form
  815            * of a point specifying the object's top-left corner in the screen's
  816            * coordinate space.
  817            *
  818            * @return an instance of <code>Point</code> representing the
  819            *    top-left corner of the object's bounds in the coordinate
  820            *    space of the screen; <code>null</code> if
  821            *    this object or its parent are not on the screen
  822            */
  823           public Point getLocation() {
  824               return null; // Not supported for MenuComponents
  825           }
  826   
  827           /**
  828            * Sets the location of the object relative to the parent.
  829            */
  830           public void setLocation(Point p) {
  831               // Not supported for MenuComponents
  832           }
  833   
  834           /**
  835            * Gets the bounds of this object in the form of a
  836            * <code>Rectangle</code> object.
  837            * The bounds specify this object's width, height, and location
  838            * relative to its parent.
  839            *
  840            * @return a rectangle indicating this component's bounds;
  841            *     <code>null</code> if this object is not on the screen
  842            */
  843           public Rectangle getBounds() {
  844               return null; // Not supported for MenuComponents
  845           }
  846   
  847           /**
  848            * Sets the bounds of this object in the form of a
  849            * <code>Rectangle</code> object.
  850            * The bounds specify this object's width, height, and location
  851            * relative to its parent.
  852            *
  853            * @param r a rectangle indicating this component's bounds
  854            */
  855           public void setBounds(Rectangle r) {
  856               // Not supported for MenuComponents
  857           }
  858   
  859           /**
  860            * Returns the size of this object in the form of a
  861            * <code>Dimension</code> object. The height field of
  862            * the <code>Dimension</code> object contains this object's
  863            * height, and the width field of the <code>Dimension</code>
  864            * object contains this object's width.
  865            *
  866            * @return a <code>Dimension</code> object that indicates the
  867            *         size of this component; <code>null</code>
  868            *         if this object is not on the screen
  869            */
  870           public Dimension getSize() {
  871               return null; // Not supported for MenuComponents
  872           }
  873   
  874           /**
  875            * Resizes this object.
  876            *
  877            * @param d - the <code>Dimension</code> specifying the
  878            *    new size of the object
  879            */
  880           public void setSize(Dimension d) {
  881               // Not supported for MenuComponents
  882           }
  883   
  884           /**
  885            * Returns the <code>Accessible</code> child, if one exists,
  886            * contained at the local coordinate <code>Point</code>.
  887            * If there is no <code>Accessible</code> child, <code>null</code>
  888            * is returned.
  889            *
  890            * @param p the point defining the top-left corner of the
  891            *    <code>Accessible</code>, given in the coordinate space
  892            *    of the object's parent
  893            * @return the <code>Accessible</code>, if it exists,
  894            *    at the specified location; else <code>null</code>
  895            */
  896           public Accessible getAccessibleAt(Point p) {
  897               return null; // MenuComponents don't have children
  898           }
  899   
  900           /**
  901            * Returns whether this object can accept focus or not.
  902            *
  903            * @return true if object can accept focus; otherwise false
  904            */
  905           public boolean isFocusTraversable() {
  906               return true; // Not supported for MenuComponents
  907           }
  908   
  909           /**
  910            * Requests focus for this object.
  911            */
  912           public void requestFocus() {
  913               // Not supported for MenuComponents
  914           }
  915   
  916           /**
  917            * Adds the specified focus listener to receive focus events from this
  918            * component.
  919            *
  920            * @param l the focus listener
  921            */
  922           public void addFocusListener(java.awt.event.FocusListener l) {
  923               // Not supported for MenuComponents
  924           }
  925   
  926           /**
  927            * Removes the specified focus listener so it no longer receives focus
  928            * events from this component.
  929            *
  930            * @param l the focus listener
  931            */
  932           public void removeFocusListener(java.awt.event.FocusListener l) {
  933               // Not supported for MenuComponents
  934           }
  935   
  936           // AccessibleSelection methods
  937           //
  938   
  939           /**
  940            * Returns the number of <code>Accessible</code> children currently selected.
  941            * If no children are selected, the return value will be 0.
  942            *
  943            * @return the number of items currently selected
  944            */
  945            public int getAccessibleSelectionCount() {
  946                return 0;  //  To be fully implemented in a future release
  947            }
  948   
  949           /**
  950            * Returns an <code>Accessible</code> representing the specified
  951            * selected child in the object.  If there isn't a selection, or there are
  952            * fewer children selected than the integer passed in, the return
  953            * value will be <code>null</code>.
  954            * <p>Note that the index represents the i-th selected child, which
  955            * is different from the i-th child.
  956            *
  957            * @param i the zero-based index of selected children
  958            * @return the i-th selected child
  959            * @see #getAccessibleSelectionCount
  960            */
  961            public Accessible getAccessibleSelection(int i) {
  962                return null;  //  To be fully implemented in a future release
  963            }
  964   
  965           /**
  966            * Determines if the current child of this object is selected.
  967            *
  968            * @return true if the current child of this object is selected;
  969            *    else false
  970            * @param i the zero-based index of the child in this
  971            *      <code>Accessible</code> object
  972            * @see AccessibleContext#getAccessibleChild
  973            */
  974            public boolean isAccessibleChildSelected(int i) {
  975                return false;  //  To be fully implemented in a future release
  976            }
  977   
  978           /**
  979            * Adds the specified <code>Accessible</code> child of the object
  980            * to the object's selection.  If the object supports multiple selections,
  981            * the specified child is added to any existing selection, otherwise
  982            * it replaces any existing selection in the object.  If the
  983            * specified child is already selected, this method has no effect.
  984            *
  985            * @param i the zero-based index of the child
  986            * @see AccessibleContext#getAccessibleChild
  987            */
  988            public void addAccessibleSelection(int i) {
  989                  //  To be fully implemented in a future release
  990            }
  991   
  992           /**
  993            * Removes the specified child of the object from the object's
  994            * selection.  If the specified item isn't currently selected, this
  995            * method has no effect.
  996            *
  997            * @param i the zero-based index of the child
  998            * @see AccessibleContext#getAccessibleChild
  999            */
 1000            public void removeAccessibleSelection(int i) {
 1001                  //  To be fully implemented in a future release
 1002            }
 1003   
 1004           /**
 1005            * Clears the selection in the object, so that no children in the
 1006            * object are selected.
 1007            */
 1008            public void clearAccessibleSelection() {
 1009                  //  To be fully implemented in a future release
 1010            }
 1011   
 1012           /**
 1013            * Causes every child of the object to be selected
 1014            * if the object supports multiple selections.
 1015            */
 1016            public void selectAllAccessibleSelection() {
 1017                  //  To be fully implemented in a future release
 1018            }
 1019   
 1020       } // inner class AccessibleAWTComponent
 1021   
 1022       /**
 1023        * Gets the index of this object in its accessible parent.
 1024        *
 1025        * @return -1 if this object does not have an accessible parent;
 1026        *      otherwise, the index of the child in its accessible parent.
 1027        */
 1028       int getAccessibleIndexInParent() {
 1029           MenuContainer localParent = parent;
 1030           if (!(localParent instanceof MenuComponent)) {
 1031               // MenuComponents only have accessible index when inside MenuComponents
 1032               return -1;
 1033           }
 1034           MenuComponent localParentMenu = (MenuComponent)localParent;
 1035           return localParentMenu.getAccessibleChildIndex(this);
 1036       }
 1037   
 1038       /**
 1039        * Gets the index of the child within this MenuComponent.
 1040        *
 1041        * @param child MenuComponent whose index we are interested in.
 1042        * @return -1 if this object doesn't contain the child,
 1043        *      otherwise, index of the child.
 1044        */
 1045       int getAccessibleChildIndex(MenuComponent child) {
 1046           return -1; // Overridden in subclasses.
 1047       }
 1048   
 1049       /**
 1050        * Gets the state of this object.
 1051        *
 1052        * @return an instance of <code>AccessibleStateSet</code>
 1053        *     containing the current state set of the object
 1054        * @see AccessibleState
 1055        */
 1056       AccessibleStateSet getAccessibleStateSet() {
 1057           AccessibleStateSet states = new AccessibleStateSet();
 1058           return states;
 1059       }
 1060   
 1061   }

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