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    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.
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   22    * or visit www.oracle.com if you need additional information or have any
   23    * questions.
   24    */
   25   package javax.swing;
   26   
   27   
   28   import java.util;
   29   import java.awt;
   30   import java.awt.event;
   31   import java.applet;
   32   import java.beans;
   33   import javax.swing.event;
   34   import sun.awt.EmbeddedFrame;
   35   
   36   /**
   37     * The KeyboardManager class is used to help dispatch keyboard actions for the
   38     * WHEN_IN_FOCUSED_WINDOW style actions.  Actions with other conditions are handled
   39     * directly in JComponent.
   40     *
   41     * Here's a description of the symantics of how keyboard dispatching should work
   42     * atleast as I understand it.
   43     *
   44     * KeyEvents are dispatched to the focused component.  The focus manager gets first
   45     * crack at processing this event.  If the focus manager doesn't want it, then
   46     * the JComponent calls super.processKeyEvent() this allows listeners a chance
   47     * to process the event.
   48     *
   49     * If none of the listeners "consumes" the event then the keybindings get a shot.
   50     * This is where things start to get interesting.  First, KeyStokes defined with the
   51     * WHEN_FOCUSED condition get a chance.  If none of these want the event, then the component
   52     * walks though it's parents looked for actions of type WHEN_ANCESTOR_OF_FOCUSED_COMPONENT.
   53     *
   54     * If no one has taken it yet, then it winds up here.  We then look for components registered
   55     * for WHEN_IN_FOCUSED_WINDOW events and fire to them.  Note that if none of those are found
   56     * then we pass the event to the menubars and let them have a crack at it.  They're handled differently.
   57     *
   58     * Lastly, we check if we're looking at an internal frame.  If we are and no one wanted the event
   59     * then we move up to the InternalFrame's creator and see if anyone wants the event (and so on and so on).
   60     *
   61     *
   62     * @see InputMap
   63     */
   64   class KeyboardManager {
   65   
   66       static KeyboardManager currentManager = new KeyboardManager();
   67   
   68       /**
   69         * maps top-level containers to a sub-hashtable full of keystrokes
   70         */
   71       Hashtable<Container, Hashtable> containerMap = new Hashtable<Container, Hashtable>();
   72   
   73       /**
   74         * Maps component/keystroke pairs to a topLevel container
   75         * This is mainly used for fast unregister operations
   76         */
   77       Hashtable<ComponentKeyStrokePair, Container> componentKeyStrokeMap = new Hashtable<ComponentKeyStrokePair, Container>();
   78   
   79       public static KeyboardManager getCurrentManager() {
   80           return currentManager;
   81       }
   82   
   83       public static void setCurrentManager(KeyboardManager km) {
   84           currentManager = km;
   85       }
   86   
   87       /**
   88         * register keystrokes here which are for the WHEN_IN_FOCUSED_WINDOW
   89         * case.
   90         * Other types of keystrokes will be handled by walking the hierarchy
   91         * That simplifies some potentially hairy stuff.
   92         */
   93        public void registerKeyStroke(KeyStroke k, JComponent c) {
   94            Container topContainer = getTopAncestor(c);
   95            if (topContainer == null) {
   96                return;
   97            }
   98            Hashtable keyMap = containerMap.get(topContainer);
   99   
  100            if (keyMap ==  null) {  // lazy evaluate one
  101                keyMap = registerNewTopContainer(topContainer);
  102            }
  103   
  104            Object tmp = keyMap.get(k);
  105            if (tmp == null) {
  106                keyMap.put(k,c);
  107            } else if (tmp instanceof Vector) {  // if there's a Vector there then add to it.
  108                Vector v = (Vector)tmp;
  109                if (!v.contains(c)) {  // only add if this keystroke isn't registered for this component
  110                    v.addElement(c);
  111                }
  112            } else if (tmp instanceof JComponent) {
  113              // if a JComponent is there then remove it and replace it with a vector
  114              // Then add the old compoennt and the new compoent to the vector
  115              // then insert the vector in the table
  116              if (tmp != c) {  // this means this is already registered for this component, no need to dup
  117                  Vector<JComponent> v = new Vector<JComponent>();
  118                  v.addElement((JComponent) tmp);
  119                  v.addElement(c);
  120                  keyMap.put(k, v);
  121              }
  122            } else {
  123                System.out.println("Unexpected condition in registerKeyStroke");
  124                Thread.dumpStack();
  125            }
  126   
  127            componentKeyStrokeMap.put(new ComponentKeyStrokePair(c,k), topContainer);
  128   
  129            // Check for EmbeddedFrame case, they know how to process accelerators even
  130            // when focus is not in Java
  131            if (topContainer instanceof EmbeddedFrame) {
  132                ((EmbeddedFrame)topContainer).registerAccelerator(k);
  133            }
  134        }
  135   
  136        /**
  137          * Find the top focusable Window, Applet, or InternalFrame
  138          */
  139        private static Container getTopAncestor(JComponent c) {
  140           for(Container p = c.getParent(); p != null; p = p.getParent()) {
  141               if (p instanceof Window && ((Window)p).isFocusableWindow() ||
  142                   p instanceof Applet || p instanceof JInternalFrame) {
  143   
  144                   return p;
  145               }
  146           }
  147           return null;
  148        }
  149   
  150        public void unregisterKeyStroke(KeyStroke ks, JComponent c) {
  151   
  152          // component may have already been removed from the hierarchy, we
  153          // need to look up the container using the componentKeyStrokeMap.
  154   
  155            ComponentKeyStrokePair ckp = new ComponentKeyStrokePair(c,ks);
  156   
  157            Container topContainer = componentKeyStrokeMap.get(ckp);
  158   
  159            if (topContainer == null) {  // never heard of this pairing, so bail
  160                return;
  161            }
  162   
  163            Hashtable keyMap = containerMap.get(topContainer);
  164            if  (keyMap == null) { // this should never happen, but I'm being safe
  165                Thread.dumpStack();
  166                return;
  167            }
  168   
  169            Object tmp = keyMap.get(ks);
  170            if (tmp == null) {  // this should never happen, but I'm being safe
  171                Thread.dumpStack();
  172                return;
  173            }
  174   
  175            if (tmp instanceof JComponent && tmp == c) {
  176                keyMap.remove(ks);  // remove the KeyStroke from the Map
  177                //System.out.println("removed a stroke" + ks);
  178            } else if (tmp instanceof Vector ) {  // this means there is more than one component reg for this key
  179                Vector v = (Vector)tmp;
  180                v.removeElement(c);
  181                if ( v.isEmpty() ) {
  182                    keyMap.remove(ks);  // remove the KeyStroke from the Map
  183                    //System.out.println("removed a ks vector");
  184                }
  185            }
  186   
  187            if ( keyMap.isEmpty() ) {  // if no more bindings in this table
  188                containerMap.remove(topContainer);  // remove table to enable GC
  189                //System.out.println("removed a container");
  190            }
  191   
  192            componentKeyStrokeMap.remove(ckp);
  193   
  194            // Check for EmbeddedFrame case, they know how to process accelerators even
  195            // when focus is not in Java
  196            if (topContainer instanceof EmbeddedFrame) {
  197                ((EmbeddedFrame)topContainer).unregisterAccelerator(ks);
  198            }
  199        }
  200   
  201       /**
  202         * This method is called when the focused component (and none of
  203         * its ancestors) want the key event.  This will look up the keystroke
  204         * to see if any chidren (or subchildren) of the specified container
  205         * want a crack at the event.
  206         * If one of them wants it, then it will "DO-THE-RIGHT-THING"
  207         */
  208       public boolean fireKeyboardAction(KeyEvent e, boolean pressed, Container topAncestor) {
  209   
  210            if (e.isConsumed()) {
  211                 System.out.println("Aquired pre-used event!");
  212                 Thread.dumpStack();
  213            }
  214   
  215            // There may be two keystrokes associated with a low-level key event;
  216            // in this case a keystroke made of an extended key code has a priority.
  217            KeyStroke ks;
  218            KeyStroke ksE = null;
  219   
  220   
  221            if(e.getID() == KeyEvent.KEY_TYPED) {
  222                  ks=KeyStroke.getKeyStroke(e.getKeyChar());
  223            } else {
  224                  if(e.getKeyCode() != e.getExtendedKeyCode()) {
  225                      ksE=KeyStroke.getKeyStroke(e.getExtendedKeyCode(), e.getModifiers(), !pressed);
  226                  }
  227                  ks=KeyStroke.getKeyStroke(e.getKeyCode(), e.getModifiers(), !pressed);
  228            }
  229   
  230            Hashtable keyMap = containerMap.get(topAncestor);
  231            if (keyMap != null) { // this container isn't registered, so bail
  232   
  233                Object tmp = null;
  234                // extended code has priority
  235                if( ksE != null ) {
  236                    tmp = keyMap.get(ksE);
  237                    if( tmp != null ) {
  238                        ks = ksE;
  239                    }
  240                }
  241                if( tmp == null ) {
  242                    tmp = keyMap.get(ks);
  243                }
  244   
  245                if (tmp == null) {
  246                  // don't do anything
  247                } else if ( tmp instanceof JComponent) {
  248                    JComponent c = (JComponent)tmp;
  249                    if ( c.isShowing() && c.isEnabled() ) { // only give it out if enabled and visible
  250                        fireBinding(c, ks, e, pressed);
  251                    }
  252                } else if ( tmp instanceof Vector) { //more than one comp registered for this
  253                    Vector v = (Vector)tmp;
  254                    // There is no well defined order for WHEN_IN_FOCUSED_WINDOW
  255                    // bindings, but we give precedence to those bindings just
  256                    // added. This is done so that JMenus WHEN_IN_FOCUSED_WINDOW
  257                    // bindings are accessed before those of the JRootPane (they
  258                    // both have a WHEN_IN_FOCUSED_WINDOW binding for enter).
  259                    for (int counter = v.size() - 1; counter >= 0; counter--) {
  260                        JComponent c = (JComponent)v.elementAt(counter);
  261                        //System.out.println("Trying collision: " + c + " vector = "+ v.size());
  262                        if ( c.isShowing() && c.isEnabled() ) { // don't want to give these out
  263                            fireBinding(c, ks, e, pressed);
  264                            if (e.isConsumed())
  265                                return true;
  266                        }
  267                    }
  268                } else  {
  269                    System.out.println( "Unexpected condition in fireKeyboardAction " + tmp);
  270                    // This means that tmp wasn't null, a JComponent, or a Vector.  What is it?
  271                    Thread.dumpStack();
  272                }
  273            }
  274   
  275            if (e.isConsumed()) {
  276                return true;
  277            }
  278            // if no one else handled it, then give the menus a crack
  279            // The're handled differently.  The key is to let any JMenuBars
  280            // process the event
  281            if ( keyMap != null) {
  282                Vector v = (Vector)keyMap.get(JMenuBar.class);
  283                if (v != null) {
  284                    Enumeration iter = v.elements();
  285                    while (iter.hasMoreElements()) {
  286                        JMenuBar mb = (JMenuBar)iter.nextElement();
  287                        if ( mb.isShowing() && mb.isEnabled() ) { // don't want to give these out
  288                            if( !(ks.equals(ksE)) ) {
  289                                fireBinding(mb, ksE, e, pressed);
  290                            }
  291                            if(ks.equals(ksE) || !e.isConsumed()) {
  292                                fireBinding(mb, ks, e, pressed);
  293                            }
  294                            if (e.isConsumed()) {
  295                                return true;
  296                            }
  297                        }
  298                    }
  299                }
  300            }
  301   
  302            return e.isConsumed();
  303       }
  304   
  305       void fireBinding(JComponent c, KeyStroke ks, KeyEvent e, boolean pressed) {
  306           if (c.processKeyBinding(ks, e, JComponent.WHEN_IN_FOCUSED_WINDOW,
  307                                   pressed)) {
  308               e.consume();
  309           }
  310       }
  311   
  312       public void registerMenuBar(JMenuBar mb) {
  313           Container top = getTopAncestor(mb);
  314           if (top == null) {
  315               return;
  316           }
  317           Hashtable keyMap = containerMap.get(top);
  318   
  319           if (keyMap ==  null) {  // lazy evaluate one
  320                keyMap = registerNewTopContainer(top);
  321           }
  322           // use the menubar class as the key
  323           Vector menuBars = (Vector)keyMap.get(JMenuBar.class);
  324   
  325           if (menuBars == null) {  // if we don't have a list of menubars,
  326                                    // then make one.
  327               menuBars = new Vector();
  328               keyMap.put(JMenuBar.class, menuBars);
  329           }
  330   
  331           if (!menuBars.contains(mb)) {
  332               menuBars.addElement(mb);
  333           }
  334       }
  335   
  336   
  337       public void unregisterMenuBar(JMenuBar mb) {
  338           Container topContainer = getTopAncestor(mb);
  339           if (topContainer == null) {
  340               return;
  341           }
  342           Hashtable keyMap = containerMap.get(topContainer);
  343           if (keyMap!=null) {
  344               Vector v = (Vector)keyMap.get(JMenuBar.class);
  345               if (v != null) {
  346                   v.removeElement(mb);
  347                   if (v.isEmpty()) {
  348                       keyMap.remove(JMenuBar.class);
  349                       if (keyMap.isEmpty()) {
  350                           // remove table to enable GC
  351                           containerMap.remove(topContainer);
  352                       }
  353                   }
  354               }
  355           }
  356       }
  357       protected Hashtable registerNewTopContainer(Container topContainer) {
  358                Hashtable keyMap = new Hashtable();
  359                containerMap.put(topContainer, keyMap);
  360                return keyMap;
  361       }
  362   
  363       /**
  364         * This class is used to create keys for a hashtable
  365         * which looks up topContainers based on component, keystroke pairs
  366         * This is used to make unregistering KeyStrokes fast
  367         */
  368       class ComponentKeyStrokePair {
  369           Object component;
  370           Object keyStroke;
  371   
  372           public ComponentKeyStrokePair(Object comp, Object key) {
  373               component = comp;
  374               keyStroke = key;
  375           }
  376   
  377           public boolean equals(Object o) {
  378               if ( !(o instanceof ComponentKeyStrokePair)) {
  379                   return false;
  380               }
  381               ComponentKeyStrokePair ckp = (ComponentKeyStrokePair)o;
  382               return ((component.equals(ckp.component)) && (keyStroke.equals(ckp.keyStroke)));
  383           }
  384   
  385           public int hashCode() {
  386               return component.hashCode() * keyStroke.hashCode();
  387           }
  388   
  389       }
  390   
  391   } // end KeyboardManager

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