1 /*
   2  * Copyright (c) 2011, 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 
  26 package javafx.embed.swing;
  27 
  28 import java.awt.AWTEvent;
  29 import java.awt.Container;
  30 import java.awt.event.KeyAdapter;
  31 import java.lang.reflect.Constructor;
  32 import java.lang.reflect.Field;
  33 import java.lang.reflect.Method;
  34 
  35 import javax.swing.JComponent;
  36 
  37 class SwingEventDispatcherHelper {
  38     
  39     private static final long MOUSE_MASK = AWTEvent.MOUSE_EVENT_MASK |
  40                                            AWTEvent.MOUSE_MOTION_EVENT_MASK |
  41                                            AWTEvent.MOUSE_WHEEL_EVENT_MASK;
  42     
  43     private static Field dispatcherField;
  44     private static Constructor<?> newLightweightDispatcher;
  45     private static Method dispatchMethod;
  46     private static Method enableEvents;
  47 
  48     // grab this idea from CacioCavallo
  49     static void initReflection() {
  50         try {
  51             
  52             // lightweight dispatcher
  53             dispatcherField = Container.class.getDeclaredField("dispatcher");
  54             dispatcherField.setAccessible(true);
  55             
  56             Class<?> dispatcherCls = Class.forName("java.awt.LightweightDispatcher");
  57             newLightweightDispatcher =
  58                     dispatcherCls.getDeclaredConstructor(new Class[] { 
  59                                                             Container.class
  60                                                          });
  61             newLightweightDispatcher.setAccessible(true);
  62             
  63             dispatchMethod = dispatcherCls.getDeclaredMethod("dispatchEvent",
  64                                                              AWTEvent.class);
  65             dispatchMethod.setAccessible(true);
  66 
  67             enableEvents = dispatcherCls.getDeclaredMethod("enableEvents",
  68                                                            new Class[] {
  69                                                                 long.class
  70                                                            });
  71             enableEvents.setAccessible(true);
  72             
  73         } catch (Exception ex) {
  74             
  75             System.err.println(ex);
  76             
  77             InternalError err = new InternalError();
  78             err.initCause(ex);
  79             throw err;
  80         }
  81     }
  82  
  83     static void setLightweightDispatcher(JComponent component) {
  84         if (dispatcherField == null) {
  85             initReflection();
  86         }
  87         try {
  88             Object dispatcher = newLightweightDispatcher.newInstance(component);
  89             enableEvents.invoke(dispatcher, MOUSE_MASK | AWTEvent.KEY_EVENT_MASK);
  90             dispatcherField.set(component, dispatcher);
  91             component.addKeyListener(new KeyAdapter(){});
  92         } catch (Exception e) {
  93             e.printStackTrace();
  94         }
  95     }
  96     
  97     /**
  98      * Performs lightweight dispatching for the specified event on this window.
  99      * This only calls the lightweight dispatcher. We cannot simply
 100      * call dispatchEvent() because that would also send the event to the
 101      * Toolkit dispatching mechanism (AWTEventListener, etc), which has ugly
 102      * side effects, like popups closing too early.
 103      *
 104      * @param e the event to be dispatched
 105      */
 106     static void dispatchEvent(AWTEvent awtEvent, JComponent component) {
 107 
 108             if (dispatcherField == null) {
 109                 initReflection();
 110             }
 111             try {
 112                 Object dispatcher = dispatcherField.get(component);
 113                 if (dispatcher != null) {
 114                     dispatchMethod.invoke(dispatcher, awtEvent);
 115                 }
 116             } catch (Exception ex) {
 117                 InternalError err = new InternalError();
 118                 err.initCause(ex);
 119                 throw err;
 120             }
 121 
 122 
 123     }
 124 }