1 /*
   2  * Copyright (c) 1998, 2009, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 package 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.AWTAccessor;
  35 import sun.awt.EmbeddedFrame;
  36 
  37 /**
  38   * The KeyboardManager class is used to help dispatch keyboard actions for the
  39   * WHEN_IN_FOCUSED_WINDOW style actions.  Actions with other conditions are handled
  40   * directly in JComponent.
  41   *
  42   * Here's a description of the symantics of how keyboard dispatching should work
  43   * atleast as I understand it.
  44   *
  45   * KeyEvents are dispatched to the focused component.  The focus manager gets first
  46   * crack at processing this event.  If the focus manager doesn't want it, then
  47   * the JComponent calls super.processKeyEvent() this allows listeners a chance
  48   * to process the event.
  49   *
  50   * If none of the listeners "consumes" the event then the keybindings get a shot.
  51   * This is where things start to get interesting.  First, KeyStokes defined with the
  52   * WHEN_FOCUSED condition get a chance.  If none of these want the event, then the component
  53   * walks though it's parents looked for actions of type WHEN_ANCESTOR_OF_FOCUSED_COMPONENT.
  54   *
  55   * If no one has taken it yet, then it winds up here.  We then look for components registered
  56   * for WHEN_IN_FOCUSED_WINDOW events and fire to them.  Note that if none of those are found
  57   * then we pass the event to the menubars and let them have a crack at it.  They're handled differently.
  58   *
  59   * Lastly, we check if we're looking at an internal frame.  If we are and no one wanted the event
  60   * then we move up to the InternalFrame's creator and see if anyone wants the event (and so on and so on).
  61   *
  62   *
  63   * @see InputMap
  64   */
  65 class KeyboardManager {
  66 
  67     static KeyboardManager currentManager = new KeyboardManager();
  68 
  69     /**
  70       * maps top-level containers to a sub-hashtable full of keystrokes
  71       */
  72     Hashtable<Container, Hashtable> containerMap = new Hashtable<Container, Hashtable>();
  73 
  74     /**
  75       * Maps component/keystroke pairs to a topLevel container
  76       * This is mainly used for fast unregister operations
  77       */
  78     Hashtable<ComponentKeyStrokePair, Container> componentKeyStrokeMap = new Hashtable<ComponentKeyStrokePair, Container>();
  79 
  80     public static KeyboardManager getCurrentManager() {
  81         return currentManager;
  82     }
  83 
  84     public static void setCurrentManager(KeyboardManager km) {
  85         currentManager = km;
  86     }
  87 
  88     /**
  89       * register keystrokes here which are for the WHEN_IN_FOCUSED_WINDOW
  90       * case.
  91       * Other types of keystrokes will be handled by walking the hierarchy
  92       * That simplifies some potentially hairy stuff.
  93       */
  94      public void registerKeyStroke(KeyStroke k, JComponent c) {
  95          Container topContainer = getTopAncestor(c);
  96          if (topContainer == null) {
  97              return;
  98          }
  99          Hashtable keyMap = containerMap.get(topContainer);
 100 
 101          if (keyMap ==  null) {  // lazy evaluate one
 102              keyMap = registerNewTopContainer(topContainer);
 103          }
 104 
 105          Object tmp = keyMap.get(k);
 106          if (tmp == null) {
 107              keyMap.put(k,c);
 108          } else if (tmp instanceof Vector) {  // if there's a Vector there then add to it.
 109              Vector v = (Vector)tmp;
 110              if (!v.contains(c)) {  // only add if this keystroke isn't registered for this component
 111                  v.addElement(c);
 112              }
 113          } else if (tmp instanceof JComponent) {
 114            // if a JComponent is there then remove it and replace it with a vector
 115            // Then add the old compoennt and the new compoent to the vector
 116            // then insert the vector in the table
 117            if (tmp != c) {  // this means this is already registered for this component, no need to dup
 118                Vector<JComponent> v = new Vector<JComponent>();
 119                v.addElement((JComponent) tmp);
 120                v.addElement(c);
 121                keyMap.put(k, v);
 122            }
 123          } else {
 124              System.out.println("Unexpected condition in registerKeyStroke");
 125              Thread.dumpStack();
 126          }
 127 
 128          componentKeyStrokeMap.put(new ComponentKeyStrokePair(c,k), topContainer);
 129 
 130          // Check for EmbeddedFrame case, they know how to process accelerators even
 131          // when focus is not in Java
 132          if (topContainer instanceof EmbeddedFrame) {
 133              ((EmbeddedFrame)topContainer).registerAccelerator(k);
 134          }
 135      }
 136 
 137      /**
 138        * Find the top focusable Window, Applet, or InternalFrame
 139        */
 140      private static Container getTopAncestor(JComponent c) {
 141         for(Container p = c.getParent(); p != null; p = p.getParent()) {
 142             if (p instanceof Window && ((Window)p).isFocusableWindow() ||
 143                 p instanceof Applet || p instanceof JInternalFrame) {
 144 
 145                 return p;
 146             }
 147         }
 148         return null;
 149      }
 150 
 151      public void unregisterKeyStroke(KeyStroke ks, JComponent c) {
 152 
 153        // component may have already been removed from the hierarchy, we
 154        // need to look up the container using the componentKeyStrokeMap.
 155 
 156          ComponentKeyStrokePair ckp = new ComponentKeyStrokePair(c,ks);
 157 
 158          Container topContainer = componentKeyStrokeMap.get(ckp);
 159 
 160          if (topContainer == null) {  // never heard of this pairing, so bail
 161              return;
 162          }
 163 
 164          Hashtable keyMap = containerMap.get(topContainer);
 165          if  (keyMap == null) { // this should never happen, but I'm being safe
 166              Thread.dumpStack();
 167              return;
 168          }
 169 
 170          Object tmp = keyMap.get(ks);
 171          if (tmp == null) {  // this should never happen, but I'm being safe
 172              Thread.dumpStack();
 173              return;
 174          }
 175 
 176          if (tmp instanceof JComponent && tmp == c) {
 177              keyMap.remove(ks);  // remove the KeyStroke from the Map
 178              //System.out.println("removed a stroke" + ks);
 179          } else if (tmp instanceof Vector ) {  // this means there is more than one component reg for this key
 180              Vector v = (Vector)tmp;
 181              v.removeElement(c);
 182              if ( v.isEmpty() ) {
 183                  keyMap.remove(ks);  // remove the KeyStroke from the Map
 184                  //System.out.println("removed a ks vector");
 185              }
 186          }
 187 
 188          if ( keyMap.isEmpty() ) {  // if no more bindings in this table
 189              containerMap.remove(topContainer);  // remove table to enable GC
 190              //System.out.println("removed a container");
 191          }
 192 
 193          componentKeyStrokeMap.remove(ckp);
 194 
 195          // Check for EmbeddedFrame case, they know how to process accelerators even
 196          // when focus is not in Java
 197          if (topContainer instanceof EmbeddedFrame) {
 198              ((EmbeddedFrame)topContainer).unregisterAccelerator(ks);
 199          }
 200      }
 201 
 202     /**
 203       * This method is called when the focused component (and none of
 204       * its ancestors) want the key event.  This will look up the keystroke
 205       * to see if any chidren (or subchildren) of the specified container
 206       * want a crack at the event.
 207       * If one of them wants it, then it will "DO-THE-RIGHT-THING"
 208       */
 209     public boolean fireKeyboardAction(KeyEvent e, boolean pressed, Container topAncestor) {
 210 
 211          if (e.isConsumed()) {
 212               System.out.println("Aquired pre-used event!");
 213               Thread.dumpStack();
 214          }
 215 
 216          // There may be two keystrokes associated with a low-level key event;
 217          // in this case a keystroke made of an extended key code has a priority.
 218          KeyStroke ks;
 219          KeyStroke ksE = null;
 220 
 221 
 222          if(e.getID() == KeyEvent.KEY_TYPED) {
 223              ks=KeyStroke.getKeyStroke(e.getKeyChar());
 224          } else {
 225              int ekc = AWTAccessor.getKeyEventAccessor().getExtendedKeyCode(e);
 226                if(e.getKeyCode() != ekc) {
 227                    ksE=KeyStroke.getKeyStroke(ekc, e.getModifiers(), !pressed);
 228                }
 229                ks=KeyStroke.getKeyStroke(e.getKeyCode(), e.getModifiers(), !pressed);
 230          }
 231 
 232          Hashtable keyMap = containerMap.get(topAncestor);
 233          if (keyMap != null) { // this container isn't registered, so bail
 234 
 235              Object tmp = null;
 236              // extended code has priority
 237              if( ksE != null ) {
 238                  tmp = keyMap.get(ksE);
 239                  if( tmp != null ) {
 240                      ks = ksE;
 241                  }
 242              }
 243              if( tmp == null ) {
 244                  tmp = keyMap.get(ks);
 245              }
 246 
 247              if (tmp == null) {
 248                // don't do anything
 249              } else if ( tmp instanceof JComponent) {
 250                  JComponent c = (JComponent)tmp;
 251                  if ( c.isShowing() && c.isEnabled() ) { // only give it out if enabled and visible
 252                      fireBinding(c, ks, e, pressed);
 253                  }
 254              } else if ( tmp instanceof Vector) { //more than one comp registered for this
 255                  Vector v = (Vector)tmp;
 256                  // There is no well defined order for WHEN_IN_FOCUSED_WINDOW
 257                  // bindings, but we give precedence to those bindings just
 258                  // added. This is done so that JMenus WHEN_IN_FOCUSED_WINDOW
 259                  // bindings are accessed before those of the JRootPane (they
 260                  // both have a WHEN_IN_FOCUSED_WINDOW binding for enter).
 261                  for (int counter = v.size() - 1; counter >= 0; counter--) {
 262                      JComponent c = (JComponent)v.elementAt(counter);
 263                      //System.out.println("Trying collision: " + c + " vector = "+ v.size());
 264                      if ( c.isShowing() && c.isEnabled() ) { // don't want to give these out
 265                          fireBinding(c, ks, e, pressed);
 266                          if (e.isConsumed())
 267                              return true;
 268                      }
 269                  }
 270              } else  {
 271                  System.out.println( "Unexpected condition in fireKeyboardAction " + tmp);
 272                  // This means that tmp wasn't null, a JComponent, or a Vector.  What is it?
 273                  Thread.dumpStack();
 274              }
 275          }
 276 
 277          if (e.isConsumed()) {
 278              return true;
 279          }
 280          // if no one else handled it, then give the menus a crack
 281          // The're handled differently.  The key is to let any JMenuBars
 282          // process the event
 283          if ( keyMap != null) {
 284              Vector v = (Vector)keyMap.get(JMenuBar.class);
 285              if (v != null) {
 286                  Enumeration iter = v.elements();
 287                  while (iter.hasMoreElements()) {
 288                      JMenuBar mb = (JMenuBar)iter.nextElement();
 289                      if ( mb.isShowing() && mb.isEnabled() ) { // don't want to give these out
 290                          if( !(ks.equals(ksE)) ) {
 291                              fireBinding(mb, ksE, e, pressed);
 292                          }
 293                          if(ks.equals(ksE) || !e.isConsumed()) {
 294                              fireBinding(mb, ks, e, pressed);
 295                          }
 296                          if (e.isConsumed()) {
 297                              return true;
 298                          }
 299                      }
 300                  }
 301              }
 302          }
 303 
 304          return e.isConsumed();
 305     }
 306 
 307     void fireBinding(JComponent c, KeyStroke ks, KeyEvent e, boolean pressed) {
 308         if (c.processKeyBinding(ks, e, JComponent.WHEN_IN_FOCUSED_WINDOW,
 309                                 pressed)) {
 310             e.consume();
 311         }
 312     }
 313 
 314     public void registerMenuBar(JMenuBar mb) {
 315         Container top = getTopAncestor(mb);
 316         if (top == null) {
 317             return;
 318         }
 319         Hashtable keyMap = containerMap.get(top);
 320 
 321         if (keyMap ==  null) {  // lazy evaluate one
 322              keyMap = registerNewTopContainer(top);
 323         }
 324         // use the menubar class as the key
 325         Vector menuBars = (Vector)keyMap.get(JMenuBar.class);
 326 
 327         if (menuBars == null) {  // if we don't have a list of menubars,
 328                                  // then make one.
 329             menuBars = new Vector();
 330             keyMap.put(JMenuBar.class, menuBars);
 331         }
 332 
 333         if (!menuBars.contains(mb)) {
 334             menuBars.addElement(mb);
 335         }
 336     }
 337 
 338 
 339     public void unregisterMenuBar(JMenuBar mb) {
 340         Container topContainer = getTopAncestor(mb);
 341         if (topContainer == null) {
 342             return;
 343         }
 344         Hashtable keyMap = containerMap.get(topContainer);
 345         if (keyMap!=null) {
 346             Vector v = (Vector)keyMap.get(JMenuBar.class);
 347             if (v != null) {
 348                 v.removeElement(mb);
 349                 if (v.isEmpty()) {
 350                     keyMap.remove(JMenuBar.class);
 351                     if (keyMap.isEmpty()) {
 352                         // remove table to enable GC
 353                         containerMap.remove(topContainer);
 354                     }
 355                 }
 356             }
 357         }
 358     }
 359     protected Hashtable registerNewTopContainer(Container topContainer) {
 360              Hashtable keyMap = new Hashtable();
 361              containerMap.put(topContainer, keyMap);
 362              return keyMap;
 363     }
 364 
 365     /**
 366       * This class is used to create keys for a hashtable
 367       * which looks up topContainers based on component, keystroke pairs
 368       * This is used to make unregistering KeyStrokes fast
 369       */
 370     class ComponentKeyStrokePair {
 371         Object component;
 372         Object keyStroke;
 373 
 374         public ComponentKeyStrokePair(Object comp, Object key) {
 375             component = comp;
 376             keyStroke = key;
 377         }
 378 
 379         public boolean equals(Object o) {
 380             if ( !(o instanceof ComponentKeyStrokePair)) {
 381                 return false;
 382             }
 383             ComponentKeyStrokePair ckp = (ComponentKeyStrokePair)o;
 384             return ((component.equals(ckp.component)) && (keyStroke.equals(ckp.keyStroke)));
 385         }
 386 
 387         public int hashCode() {
 388             return component.hashCode() * keyStroke.hashCode();
 389         }
 390 
 391     }
 392 
 393 } // end KeyboardManager