1 /*
   2  * Copyright (c) 1998, 2013, 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.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<Object, Object>> containerMap = new 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<>();
  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<Object, Object> 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              @SuppressWarnings("unchecked")
 109              Vector<Object> 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<>();
 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      @SuppressWarnings("deprecation")
 141      private static Container getTopAncestor(JComponent c) {
 142         for(Container p = c.getParent(); p != null; p = p.getParent()) {
 143             if (p instanceof Window && ((Window)p).isFocusableWindow() ||
 144                 p instanceof Applet || p instanceof JInternalFrame) {
 145 
 146                 return p;
 147             }
 148         }
 149         return null;
 150      }
 151 
 152      public void unregisterKeyStroke(KeyStroke ks, JComponent c) {
 153 
 154        // component may have already been removed from the hierarchy, we
 155        // need to look up the container using the componentKeyStrokeMap.
 156 
 157          ComponentKeyStrokePair ckp = new ComponentKeyStrokePair(c,ks);
 158 
 159          Container topContainer = componentKeyStrokeMap.get(ckp);
 160 
 161          if (topContainer == null) {  // never heard of this pairing, so bail
 162              return;
 163          }
 164 
 165          Hashtable<Object, Object> keyMap = containerMap.get(topContainer);
 166          if  (keyMap == null) { // this should never happen, but I'm being safe
 167              Thread.dumpStack();
 168              return;
 169          }
 170 
 171          Object tmp = keyMap.get(ks);
 172          if (tmp == null) {  // this should never happen, but I'm being safe
 173              Thread.dumpStack();
 174              return;
 175          }
 176 
 177          if (tmp instanceof JComponent && tmp == c) {
 178              keyMap.remove(ks);  // remove the KeyStroke from the Map
 179              //System.out.println("removed a stroke" + ks);
 180          } else if (tmp instanceof Vector ) {  // this means there is more than one component reg for this key
 181              Vector<?> v = (Vector)tmp;
 182              v.removeElement(c);
 183              if ( v.isEmpty() ) {
 184                  keyMap.remove(ks);  // remove the KeyStroke from the Map
 185                  //System.out.println("removed a ks vector");
 186              }
 187          }
 188 
 189          if ( keyMap.isEmpty() ) {  // if no more bindings in this table
 190              containerMap.remove(topContainer);  // remove table to enable GC
 191              //System.out.println("removed a container");
 192          }
 193 
 194          componentKeyStrokeMap.remove(ckp);
 195 
 196          // Check for EmbeddedFrame case, they know how to process accelerators even
 197          // when focus is not in Java
 198          if (topContainer instanceof EmbeddedFrame) {
 199              ((EmbeddedFrame)topContainer).unregisterAccelerator(ks);
 200          }
 201      }
 202 
 203     /**
 204       * This method is called when the focused component (and none of
 205       * its ancestors) want the key event.  This will look up the keystroke
 206       * to see if any chidren (or subchildren) of the specified container
 207       * want a crack at the event.
 208       * If one of them wants it, then it will "DO-THE-RIGHT-THING"
 209       */
 210     @SuppressWarnings("deprecation")
 211     public boolean fireKeyboardAction(KeyEvent e, boolean pressed, Container topAncestor) {
 212 
 213          if (e.isConsumed()) {
 214               System.out.println("Acquired pre-used event!");
 215               Thread.dumpStack();
 216          }
 217 
 218          // There may be two keystrokes associated with a low-level key event;
 219          // in this case a keystroke made of an extended key code has a priority.
 220          KeyStroke ks;
 221          KeyStroke ksE = null;
 222 
 223 
 224          if(e.getID() == KeyEvent.KEY_TYPED) {
 225                ks=KeyStroke.getKeyStroke(e.getKeyChar());
 226          } else {
 227                if(e.getKeyCode() != e.getExtendedKeyCode()) {
 228                    ksE=KeyStroke.getKeyStroke(e.getExtendedKeyCode(), e.getModifiers(), !pressed);
 229                }
 230                ks=KeyStroke.getKeyStroke(e.getKeyCode(), e.getModifiers(), !pressed);
 231          }
 232 
 233          Hashtable<Object, Object> keyMap = containerMap.get(topAncestor);
 234          if (keyMap != null) { // this container isn't registered, so bail
 235 
 236              Object tmp = null;
 237              // extended code has priority
 238              if( ksE != null ) {
 239                  tmp = keyMap.get(ksE);
 240                  if( tmp != null ) {
 241                      ks = ksE;
 242                  }
 243              }
 244              if( tmp == null ) {
 245                  tmp = keyMap.get(ks);
 246              }
 247 
 248              if (tmp == null) {
 249                // don't do anything
 250              } else if ( tmp instanceof JComponent) {
 251                  JComponent c = (JComponent)tmp;
 252                  if ( c.isShowing() && c.isEnabled() ) { // only give it out if enabled and visible
 253                      fireBinding(c, ks, e, pressed);
 254                  }
 255              } else if ( tmp instanceof Vector) { //more than one comp registered for this
 256                  Vector<?> v = (Vector)tmp;
 257                  // There is no well defined order for WHEN_IN_FOCUSED_WINDOW
 258                  // bindings, but we give precedence to those bindings just
 259                  // added. This is done so that JMenus WHEN_IN_FOCUSED_WINDOW
 260                  // bindings are accessed before those of the JRootPane (they
 261                  // both have a WHEN_IN_FOCUSED_WINDOW binding for enter).
 262                  for (int counter = v.size() - 1; counter >= 0; counter--) {
 263                      JComponent c = (JComponent)v.elementAt(counter);
 264                      //System.out.println("Trying collision: " + c + " vector = "+ v.size());
 265                      if ( c.isShowing() && c.isEnabled() ) { // don't want to give these out
 266                          fireBinding(c, ks, e, pressed);
 267                          if (e.isConsumed())
 268                              return true;
 269                      }
 270                  }
 271              } else  {
 272                  System.out.println( "Unexpected condition in fireKeyboardAction " + tmp);
 273                  // This means that tmp wasn't null, a JComponent, or a Vector.  What is it?
 274                  Thread.dumpStack();
 275              }
 276          }
 277 
 278          if (e.isConsumed()) {
 279              return true;
 280          }
 281          // if no one else handled it, then give the menus a crack
 282          // The're handled differently.  The key is to let any JMenuBars
 283          // process the event
 284          if ( keyMap != null) {
 285              @SuppressWarnings("unchecked")
 286              Vector<JMenuBar> v = (Vector)keyMap.get(JMenuBar.class);
 287              if (v != null) {
 288                  Enumeration<JMenuBar> iter = v.elements();
 289                  while (iter.hasMoreElements()) {
 290                      JMenuBar mb = iter.nextElement();
 291                      if ( mb.isShowing() && mb.isEnabled() ) { // don't want to give these out
 292                          boolean extended = (ksE != null) && !ksE.equals(ks);
 293                          if (extended) {
 294                              fireBinding(mb, ksE, e, pressed);
 295                          }
 296                          if (!extended || !e.isConsumed()) {
 297                              fireBinding(mb, ks, e, pressed);
 298                          }
 299                          if (e.isConsumed()) {
 300                              return true;
 301                          }
 302                      }
 303                  }
 304              }
 305          }
 306 
 307          return e.isConsumed();
 308     }
 309 
 310     void fireBinding(JComponent c, KeyStroke ks, KeyEvent e, boolean pressed) {
 311         if (c.processKeyBinding(ks, e, JComponent.WHEN_IN_FOCUSED_WINDOW,
 312                                 pressed)) {
 313             e.consume();
 314         }
 315     }
 316 
 317     public void registerMenuBar(JMenuBar mb) {
 318         Container top = getTopAncestor(mb);
 319         if (top == null) {
 320             return;
 321         }
 322         Hashtable<Object, Object> keyMap = containerMap.get(top);
 323 
 324         if (keyMap ==  null) {  // lazy evaluate one
 325              keyMap = registerNewTopContainer(top);
 326         }
 327         // use the menubar class as the key
 328         @SuppressWarnings("unchecked")
 329         Vector<Object> menuBars = (Vector)keyMap.get(JMenuBar.class);
 330 
 331         if (menuBars == null) {  // if we don't have a list of menubars,
 332                                  // then make one.
 333             menuBars = new Vector<>();
 334             keyMap.put(JMenuBar.class, menuBars);
 335         }
 336 
 337         if (!menuBars.contains(mb)) {
 338             menuBars.addElement(mb);
 339         }
 340     }
 341 
 342 
 343     public void unregisterMenuBar(JMenuBar mb) {
 344         Container topContainer = getTopAncestor(mb);
 345         if (topContainer == null) {
 346             return;
 347         }
 348         Hashtable<Object, Object> keyMap = containerMap.get(topContainer);
 349         if (keyMap!=null) {
 350             Vector<?> v = (Vector)keyMap.get(JMenuBar.class);
 351             if (v != null) {
 352                 v.removeElement(mb);
 353                 if (v.isEmpty()) {
 354                     keyMap.remove(JMenuBar.class);
 355                     if (keyMap.isEmpty()) {
 356                         // remove table to enable GC
 357                         containerMap.remove(topContainer);
 358                     }
 359                 }
 360             }
 361         }
 362     }
 363     protected Hashtable<Object, Object> registerNewTopContainer(Container topContainer) {
 364              Hashtable<Object, Object> keyMap = new Hashtable<>();
 365              containerMap.put(topContainer, keyMap);
 366              return keyMap;
 367     }
 368 
 369     /**
 370       * This class is used to create keys for a hashtable
 371       * which looks up topContainers based on component, keystroke pairs
 372       * This is used to make unregistering KeyStrokes fast
 373       */
 374     class ComponentKeyStrokePair {
 375         Object component;
 376         Object keyStroke;
 377 
 378         public ComponentKeyStrokePair(Object comp, Object key) {
 379             component = comp;
 380             keyStroke = key;
 381         }
 382 
 383         public boolean equals(Object o) {
 384             if ( !(o instanceof ComponentKeyStrokePair)) {
 385                 return false;
 386             }
 387             ComponentKeyStrokePair ckp = (ComponentKeyStrokePair)o;
 388             return ((component.equals(ckp.component)) && (keyStroke.equals(ckp.keyStroke)));
 389         }
 390 
 391         public int hashCode() {
 392             return component.hashCode() * keyStroke.hashCode();
 393         }
 394 
 395     }
 396 
 397 } // end KeyboardManager