1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
|
/*******************************************************************************
* Copyright (c) 2000, 2011 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.swt.widgets;
import org.eclipse.swt.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.internal.Compatibility;
/**
* Instances of this class provide synchronization support
* for displays. A default instance is created automatically
* for each display, and this instance is sufficient for almost
* all applications.
* <p>
* <b>IMPORTANT:</b> Typical application code <em>never</em>
* needs to deal with this class. It is provided only to
* allow applications which require non-standard
* synchronization behavior to plug in the support they
* require. <em>Subclasses which override the methods in
* this class must ensure that the superclass methods are
* invoked in their implementations</em>
* </p>
*
* @see Display#setSynchronizer
* @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
*/
public class Synchronizer {
Display display;
int messageCount;
RunnableLock [] messages;
Object messageLock = new Object ();
Thread syncThread;
static final int GROW_SIZE = 4;
static final int MESSAGE_LIMIT = 64;
//TEMPORARY CODE
static final boolean IS_CARBON = "carbon".equals (SWT.getPlatform ());
static final boolean IS_COCOA = "cocoa".equals (SWT.getPlatform ());
static final boolean IS_GTK = "gtk".equals (SWT.getPlatform ());
/**
* Constructs a new instance of this class.
*
* @param display the display to create the synchronizer on
*/
public Synchronizer (Display display) {
this.display = display;
}
void addLast (RunnableLock lock) {
boolean wake = false;
synchronized (messageLock) {
if (messages == null) messages = new RunnableLock [GROW_SIZE];
if (messageCount == messages.length) {
RunnableLock[] newMessages = new RunnableLock [messageCount + GROW_SIZE];
System.arraycopy (messages, 0, newMessages, 0, messageCount);
messages = newMessages;
}
messages [messageCount++] = lock;
wake = messageCount == 1;
}
if (wake) display.wakeThread ();
}
/**
* Causes the <code>run()</code> method of the runnable to
* be invoked by the user-interface thread at the next
* reasonable opportunity. The caller of this method continues
* to run in parallel, and is not notified when the
* runnable has completed.
*
* @param runnable code to run on the user-interface thread.
*
* @see #syncExec
*/
protected void asyncExec (Runnable runnable) {
if (runnable == null) {
//TEMPORARY CODE
if (!(IS_CARBON || IS_GTK || IS_COCOA)) {
display.wake ();
return;
}
}
addLast (new RunnableLock (runnable));
}
int getMessageCount () {
synchronized (messageLock) {
return messageCount;
}
}
void releaseSynchronizer () {
display = null;
messages = null;
messageLock = null;
syncThread = null;
}
RunnableLock removeFirst () {
synchronized (messageLock) {
if (messageCount == 0) return null;
RunnableLock lock = messages [0];
System.arraycopy (messages, 1, messages, 0, --messageCount);
messages [messageCount] = null;
if (messageCount == 0) {
if (messages.length > MESSAGE_LIMIT) messages = null;
}
return lock;
}
}
boolean runAsyncMessages () {
return runAsyncMessages (false);
}
boolean runAsyncMessages (boolean all) {
boolean run = false;
do {
RunnableLock lock = removeFirst ();
if (lock == null) return run;
run = true;
synchronized (lock) {
syncThread = lock.thread;
try {
lock.run ();
} catch (Throwable t) {
lock.throwable = t;
SWT.error (SWT.ERROR_FAILED_EXEC, t);
} finally {
syncThread = null;
lock.notifyAll ();
}
}
} while (all);
return run;
}
/**
* Causes the <code>run()</code> method of the runnable to
* be invoked by the user-interface thread at the next
* reasonable opportunity. The thread which calls this method
* is suspended until the runnable completes.
*
* @param runnable code to run on the user-interface thread.
*
* @exception SWTException <ul>
* <li>ERROR_FAILED_EXEC - if an exception occurred when executing the runnable</li>
* </ul>
*
* @see #asyncExec
*/
protected void syncExec (Runnable runnable) {
RunnableLock lock = null;
synchronized (Device.class) {
if (display == null || display.isDisposed ()) SWT.error (SWT.ERROR_DEVICE_DISPOSED);
if (!display.isValidThread ()) {
if (runnable == null) {
display.wake ();
return;
}
lock = new RunnableLock (runnable);
/*
* Only remember the syncThread for syncExec.
*/
lock.thread = Thread.currentThread();
addLast (lock);
}
}
if (lock == null) {
if (runnable != null) runnable.run ();
return;
}
synchronized (lock) {
boolean interrupted = false;
while (!lock.done ()) {
try {
lock.wait ();
} catch (InterruptedException e) {
interrupted = true;
}
}
if (interrupted) {
Compatibility.interrupt();
}
if (lock.throwable != null) {
SWT.error (SWT.ERROR_FAILED_EXEC, lock.throwable);
}
}
}
}
|
