1 /*
2 * Copyright (c) 1996, 2015, 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 java.awt;
27
28 import java.awt.event.MouseEvent;
29 import java.awt.event.ActionEvent;
30 import java.awt.event.WindowEvent;
31
32 import java.util.ArrayList;
33
34 import sun.util.logging.PlatformLogger;
35
36 import sun.awt.dnd.SunDragSourceContextPeer;
37
38 /**
39 * EventDispatchThread is a package-private AWT class which takes
40 * events off the EventQueue and dispatches them to the appropriate
41 * AWT components.
42 *
43 * The Thread starts a "permanent" event pump with a call to
44 * pumpEvents(Conditional) in its run() method. Event handlers can choose to
45 * block this event pump at any time, but should start a new pump (<b>not</b>
46 * a new EventDispatchThread) by again calling pumpEvents(Conditional). This
47 * secondary event pump will exit automatically as soon as the Conditional
48 * evaluate()s to false and an additional Event is pumped and dispatched.
49 *
50 * @author Tom Ball
51 * @author Amy Fowler
52 * @author Fred Ecks
53 * @author David Mendenhall
54 *
55 * @since 1.1
56 */
57 class EventDispatchThread extends Thread {
58
59 private static final PlatformLogger eventLog = PlatformLogger.getLogger("java.awt.event.EventDispatchThread");
60
61 private EventQueue theQueue;
62 private volatile boolean doDispatch = true;
63
64 private static final int ANY_EVENT = -1;
65
66 private ArrayList<EventFilter> eventFilters = new ArrayList<EventFilter>();
67
68 /**
69 * Must always call 5 args super-class constructor passing false
70 * to indicate not to inherit locals.
71 */
72 private EventDispatchThread() {
73 throw new UnsupportedOperationException("Must erase locals");
74 }
75
76 EventDispatchThread(ThreadGroup group, String name, EventQueue queue) {
77 super(group, null, name, 0, false);
78 setEventQueue(queue);
79 }
80
81 /*
82 * Must be called on EDT only, that's why no synchronization
83 */
84 public void stopDispatching() {
85 doDispatch = false;
86 }
87
88 public void run() {
89 try {
90 pumpEvents(new Conditional() {
91 public boolean evaluate() {
92 return true;
93 }
94 });
95 } finally {
96 getEventQueue().detachDispatchThread(this);
97 }
98 }
99
100 void pumpEvents(Conditional cond) {
101 pumpEvents(ANY_EVENT, cond);
102 }
103
104 void pumpEventsForHierarchy(Conditional cond, Component modalComponent) {
105 pumpEventsForHierarchy(ANY_EVENT, cond, modalComponent);
106 }
107
108 void pumpEvents(int id, Conditional cond) {
109 pumpEventsForHierarchy(id, cond, null);
110 }
111
112 void pumpEventsForHierarchy(int id, Conditional cond, Component modalComponent) {
113 pumpEventsForFilter(id, cond, new HierarchyEventFilter(modalComponent));
114 }
115
116 void pumpEventsForFilter(Conditional cond, EventFilter filter) {
117 pumpEventsForFilter(ANY_EVENT, cond, filter);
118 }
119
120 void pumpEventsForFilter(int id, Conditional cond, EventFilter filter) {
121 addEventFilter(filter);
122 doDispatch = true;
123 while (doDispatch && !isInterrupted() && cond.evaluate()) {
124 pumpOneEventForFilters(id);
125 }
126 removeEventFilter(filter);
127 }
128
129 void addEventFilter(EventFilter filter) {
130 if (eventLog.isLoggable(PlatformLogger.Level.FINEST)) {
131 eventLog.finest("adding the event filter: " + filter);
132 }
133 synchronized (eventFilters) {
134 if (!eventFilters.contains(filter)) {
135 if (filter instanceof ModalEventFilter) {
136 ModalEventFilter newFilter = (ModalEventFilter)filter;
137 int k = 0;
138 for (k = 0; k < eventFilters.size(); k++) {
139 EventFilter f = eventFilters.get(k);
140 if (f instanceof ModalEventFilter) {
141 ModalEventFilter cf = (ModalEventFilter)f;
142 if (cf.compareTo(newFilter) > 0) {
143 break;
144 }
145 }
146 }
147 eventFilters.add(k, filter);
148 } else {
149 eventFilters.add(filter);
150 }
151 }
152 }
153 }
154
155 void removeEventFilter(EventFilter filter) {
156 if (eventLog.isLoggable(PlatformLogger.Level.FINEST)) {
157 eventLog.finest("removing the event filter: " + filter);
158 }
159 synchronized (eventFilters) {
160 eventFilters.remove(filter);
161 }
162 }
163
164 void pumpOneEventForFilters(int id) {
165 AWTEvent event = null;
166 boolean eventOK = false;
167 try {
168 EventQueue eq = null;
169 do {
170 // EventQueue may change during the dispatching
171 eq = getEventQueue();
172
173 event = (id == ANY_EVENT) ? eq.getNextEvent() : eq.getNextEvent(id);
174
175 eventOK = true;
176 synchronized (eventFilters) {
177 for (int i = eventFilters.size() - 1; i >= 0; i--) {
178 EventFilter f = eventFilters.get(i);
179 EventFilter.FilterAction accept = f.acceptEvent(event);
180 if (accept == EventFilter.FilterAction.REJECT) {
181 eventOK = false;
182 break;
183 } else if (accept == EventFilter.FilterAction.ACCEPT_IMMEDIATELY) {
184 break;
185 }
186 }
187 }
188 eventOK = eventOK && SunDragSourceContextPeer.checkEvent(event);
189 if (!eventOK) {
190 event.consume();
191 }
192 }
193 while (eventOK == false);
194
195 if (eventLog.isLoggable(PlatformLogger.Level.FINEST)) {
196 eventLog.finest("Dispatching: " + event);
197 }
198
199 eq.dispatchEvent(event);
200 }
201 catch (ThreadDeath death) {
202 doDispatch = false;
203 throw death;
204 }
205 catch (InterruptedException interruptedException) {
206 doDispatch = false; // AppContext.dispose() interrupts all
207 // Threads in the AppContext
208 }
209 catch (Throwable e) {
210 processException(e);
211 }
212 }
213
214 private void processException(Throwable e) {
215 if (eventLog.isLoggable(PlatformLogger.Level.FINE)) {
216 eventLog.fine("Processing exception: " + e);
217 }
218 getUncaughtExceptionHandler().uncaughtException(this, e);
219 }
220
221 public synchronized EventQueue getEventQueue() {
222 return theQueue;
223 }
224 public synchronized void setEventQueue(EventQueue eq) {
225 theQueue = eq;
226 }
227
228 private static class HierarchyEventFilter implements EventFilter {
229 private Component modalComponent;
230 public HierarchyEventFilter(Component modalComponent) {
231 this.modalComponent = modalComponent;
232 }
233 public FilterAction acceptEvent(AWTEvent event) {
234 if (modalComponent != null) {
235 int eventID = event.getID();
236 boolean mouseEvent = (eventID >= MouseEvent.MOUSE_FIRST) &&
237 (eventID <= MouseEvent.MOUSE_LAST);
238 boolean actionEvent = (eventID >= ActionEvent.ACTION_FIRST) &&
239 (eventID <= ActionEvent.ACTION_LAST);
240 boolean windowClosingEvent = (eventID == WindowEvent.WINDOW_CLOSING);
241 /*
242 * filter out MouseEvent and ActionEvent that's outside
243 * the modalComponent hierarchy.
244 * KeyEvent is handled by using enqueueKeyEvent
245 * in Dialog.show
246 */
247 if (Component.isInstanceOf(modalComponent, "javax.swing.JInternalFrame")) {
248 /*
249 * Modal internal frames are handled separately. If event is
250 * for some component from another heavyweight than modalComp,
251 * it is accepted. If heavyweight is the same - we still accept
252 * event and perform further filtering in LightweightDispatcher
253 */
254 return windowClosingEvent ? FilterAction.REJECT : FilterAction.ACCEPT;
255 }
256 if (mouseEvent || actionEvent || windowClosingEvent) {
257 Object o = event.getSource();
258 if (o instanceof sun.awt.ModalExclude) {
259 // Exclude this object from modality and
260 // continue to pump it's events.
261 return FilterAction.ACCEPT;
262 } else if (o instanceof Component) {
263 Component c = (Component) o;
264 // 5.0u3 modal exclusion
265 boolean modalExcluded = false;
266 if (modalComponent instanceof Container) {
267 while (c != modalComponent && c != null) {
268 if ((c instanceof Window) &&
269 (sun.awt.SunToolkit.isModalExcluded((Window)c))) {
270 // Exclude this window and all its children from
271 // modality and continue to pump it's events.
272 modalExcluded = true;
273 break;
274 }
275 c = c.getParent();
276 }
277 }
278 if (!modalExcluded && (c != modalComponent)) {
279 return FilterAction.REJECT;
280 }
281 }
282 }
283 }
284 return FilterAction.ACCEPT;
285 }
286 }
287 }