C++/Qt/QThread
Содержание
Extends QThread to create thread
<source lang="cpp">
Foundations of Qt Development\Chapter12\inorderthreads\main.cpp /*
* Copyright (c) 2006-2007, Johan Thelin * * All rights reserved. * * Redistribution and use in source and binary forms, with or without modification, * are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * Neither the name of APress nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * */
- include <QApplication>
- include <QThread>
- include <QMutex>
- include <QMessageBox>
- include <QtDebug>
class TextThread : public QThread { public:
TextThread( QString text ); void run();
private:
QString m_text;
}; bool stopThreads = false; TextThread::TextThread( QString text ) : QThread() {
m_text = text;
} QMutex mutex; void TextThread::run() {
while( !stopThreads ) { mutex.lock(); if( stopThreads ) return; qDebug() << m_text; sleep( 1 ); mutex.unlock(); }
} int main( int argc, char **argv ) {
QApplication app( argc, argv ); TextThread foo( "Foo" ), bar( "Bar" ); foo.start(); bar.start(); QMessageBox::information( 0, "Threading", "Close me to stop!" ); stopThreads = true; foo.wait(); bar.wait(); return 0;
}
</source>
Producer and consumer by Qt thread
<source lang="cpp">
Foundations of Qt Development\Chapter12\competingsemaphore\main.cpp /*
* Copyright (c) 2006-2007, Johan Thelin * * All rights reserved. * * Redistribution and use in source and binary forms, with or without modification, * are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * Neither the name of APress nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * */
- include <QApplication>
- include <QThread>
- include <QSemaphore>
- include <QMutex>
- include <QtDebug>
const int bufferSize = 20; QChar buffer[ bufferSize ]; QSemaphore freeSpace( bufferSize ); QSemaphore availableData( 0 ); QSemaphore atEnd( 0 ); class TextProducer : public QThread { public:
TextProducer( QString text ); void run();
private:
QString m_text;
}; TextProducer::TextProducer( QString text ) : QThread() {
atEnd.release(); m_text = text;
} void TextProducer::run() {
static int index = 0; static QMutex indexMutex; for( int i=0; i<m_text.length(); ++i ) { freeSpace.acquire(); indexMutex.lock(); buffer[ index++ % bufferSize ] = m_text.data()[ i ]; indexMutex.unlock(); if( i == m_text.length()-1 ) atEnd.acquire(); availableData.release(); }
} class TextConsumer : public QThread { public:
void run();
}; void TextConsumer::run() {
int i = 0; while( atEnd.available() || availableData.available() ) { availableData.acquire(); qDebug() << buffer[ i ]; i = (i+1) % bufferSize; freeSpace.release(); }
} int main( int argc, char **argv ) {
QApplication app( argc, argv ); TextProducer p1( "this text is written using lower case characters." "it will compete with a text written using upper case characters." ); TextProducer p2( "THIS TEXT IS WRITTEN USING UPPER CASE CHARACTERS!" "IT WILL COMPETE WITH A TEXT WRITTEN USING LOWER CASE CHARACTERS!" ); TextConsumer consumer; p1.start(); p2.start(); consumer.start(); p1.wait(); p2.wait(); consumer.wait(); return 0;
}
</source>
Thread sleeps
<source lang="cpp"> Foundations of Qt Development\Chapter12\simplethreads\main.cpp /*
* Copyright (c) 2006-2007, Johan Thelin * * All rights reserved. * * Redistribution and use in source and binary forms, with or without modification, * are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * Neither the name of APress nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * */
- include <QApplication>
- include <QThread>
- include <QMessageBox>
- include <QtDebug>
class TextThread : public QThread { public:
TextThread( QString text ); void run();
private:
QString m_text;
}; bool stopThreads = false; TextThread::TextThread( QString text ) : QThread() {
m_text = text;
} void TextThread::run() {
while( !stopThreads ) { qDebug() << m_text; sleep( 1 ); }
} int main( int argc, char **argv ) {
QApplication app( argc, argv ); TextThread foo( "Foo" ), bar( "Bar" ); foo.start(); bar.start(); QMessageBox::information( 0, "Threading", "Close me to stop!" ); stopThreads = true; foo.wait(); bar.wait(); return 0;
}
</source>
Using QThread
<source lang="cpp"> /****************************************************************************
- Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
- All rights reserved.
- Contact: Nokia Corporation (qt-info@nokia.com)
- This file is part of the documentation of the Qt Toolkit.
- $QT_BEGIN_LICENSE:LGPL$
- Commercial Usage
- Licensees holding valid Qt Commercial licenses may use this file in
- accordance with the Qt Commercial License Agreement provided with the
- Software or, alternatively, in accordance with the terms contained in
- a written agreement between you and Nokia.
- GNU Lesser General Public License Usage
- Alternatively, this file may be used under the terms of the GNU Lesser
- General Public License version 2.1 as published by the Free Software
- Foundation and appearing in the file LICENSE.LGPL included in the
- packaging of this file. Please review the following information to
- ensure the GNU Lesser General Public License version 2.1 requirements
- will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
- In addition, as a special exception, Nokia gives you certain additional
- rights. These rights are described in the Nokia Qt LGPL Exception
- version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
- GNU General Public License Usage
- Alternatively, this file may be used under the terms of the GNU
- General Public License version 3.0 as published by the Free Software
- Foundation and appearing in the file LICENSE.GPL included in the
- packaging of this file. Please review the following information to
- ensure the GNU General Public License version 3.0 requirements will be
- met: http://www.gnu.org/copyleft/gpl.html.
- If you have questions regarding the use of this file, please contact
- Nokia at qt-info@nokia.com.
- $QT_END_LICENSE$
-
- /
- include <QThread>
class MyThread : public QThread {
Q_OBJECT
protected:
void run();
};
- include <QCache>
- include <QMutex>
- include <QThreadStorage>
- include "threads.h"
void MyThread::run()
{
}
- define Counter ReentrantCounter
class Counter
{ public:
Counter() { n = 0; } void increment() { ++n; } void decrement() { --n; } int value() const { return n; }
private:
int n;
};
- undef Counter
- define Counter ThreadSafeCounter
class Counter
{ public:
Counter() { n = 0; } void increment() { QMutexLocker locker(&mutex); ++n; } void decrement() { QMutexLocker locker(&mutex); --n; } int value() const { QMutexLocker locker(&mutex); return n; }
private:
mutable QMutex mutex; int n;
};
typedef int SomeClass;
QThreadStorage<QCache<QString, SomeClass> *> caches; void cacheObject(const QString &key, SomeClass *object)
{
if (!caches.hasLocalData()) caches.setLocalData(new QCache<QString, SomeClass>); caches.localData()->insert(key, object);
} void removeFromCache(const QString &key)
{
if (!caches.hasLocalData()) return; caches.localData()->remove(key);
}
int main() {
return 0;
}
</source>
Wait condition
<source lang="cpp"> /****************************************************************************
- Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
- All rights reserved.
- Contact: Nokia Corporation (qt-info@nokia.com)
- This file is part of the examples of the Qt Toolkit.
- $QT_BEGIN_LICENSE:LGPL$
- Commercial Usage
- Licensees holding valid Qt Commercial licenses may use this file in
- accordance with the Qt Commercial License Agreement provided with the
- Software or, alternatively, in accordance with the terms contained in
- a written agreement between you and Nokia.
- GNU Lesser General Public License Usage
- Alternatively, this file may be used under the terms of the GNU Lesser
- General Public License version 2.1 as published by the Free Software
- Foundation and appearing in the file LICENSE.LGPL included in the
- packaging of this file. Please review the following information to
- ensure the GNU Lesser General Public License version 2.1 requirements
- will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
- In addition, as a special exception, Nokia gives you certain additional
- rights. These rights are described in the Nokia Qt LGPL Exception
- version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
- GNU General Public License Usage
- Alternatively, this file may be used under the terms of the GNU
- General Public License version 3.0 as published by the Free Software
- Foundation and appearing in the file LICENSE.GPL included in the
- packaging of this file. Please review the following information to
- ensure the GNU General Public License version 3.0 requirements will be
- met: http://www.gnu.org/copyleft/gpl.html.
- If you have questions regarding the use of this file, please contact
- Nokia at qt-info@nokia.com.
- $QT_END_LICENSE$
-
- /
- include <QtCore>
- include <stdio.h>
- include <stdlib.h>
const int DataSize = 100000; const int BufferSize = 8192; char buffer[BufferSize]; QWaitCondition bufferNotEmpty; QWaitCondition bufferNotFull; QMutex mutex; int numUsedBytes = 0;
class Producer : public QThread
{ public:
void run();
}; void Producer::run() {
qsrand(QTime(0,0,0).secsTo(QTime::currentTime())); for (int i = 0; i < DataSize; ++i) { mutex.lock(); if (numUsedBytes == BufferSize) bufferNotFull.wait(&mutex); mutex.unlock(); buffer[i % BufferSize] = "ACGT"[(int)qrand() % 4]; mutex.lock(); ++numUsedBytes; bufferNotEmpty.wakeAll(); mutex.unlock(); }
}
class Consumer : public QThread
{ public:
void run();
}; void Consumer::run() {
for (int i = 0; i < DataSize; ++i) { mutex.lock(); if (numUsedBytes == 0) bufferNotEmpty.wait(&mutex); mutex.unlock(); fprintf(stderr, "%c", buffer[i % BufferSize]); mutex.lock(); --numUsedBytes; bufferNotFull.wakeAll(); mutex.unlock(); } fprintf(stderr, "\n");
}
int main(int argc, char *argv[])
{
QCoreApplication app(argc, argv); Producer producer; Consumer consumer; producer.start(); consumer.start(); producer.wait(); consumer.wait(); return 0;
}
</source>