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+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Qt Software Information (qt-info@nokia.com)
+**
+** This file is part of the Qt3Support module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the either Technology Preview License Agreement or the
+** Beta Release License Agreement.
+**
+** 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 1.0, 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 are unsure which license is appropriate for your use, please
+** contact the sales department at qt-sales@nokia.com.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "q3deepcopy.h"
+
+QT_BEGIN_NAMESPACE
+
+/*!
+ \class Q3DeepCopy
+ \brief The Q3DeepCopy class is a template class which ensures that
+ implicitly shared and explicitly shared classes reference unique
+ data.
+
+ \reentrant
+
+ \compat
+
+ Normally, shared copies reference the same data to optimize memory
+ use and for maximum speed. In the example below, \c s1, \c s2, \c
+ s3, \c s4 and \c s5 share data.
+
+ \snippet doc/src/snippets/code/src_qt3support_tools_q3deepcopy.cpp 0
+
+ Q3DeepCopy can be used several ways to ensure that an object
+ references unique, unshared data. In the example below, \c s1, \c
+ s2 and \c s5 share data, while neither \c s3 nor \c s4 share data.
+ \snippet doc/src/snippets/code/src_qt3support_tools_q3deepcopy.cpp 1
+
+ In the example below, \c s1, \c s2 and \c s5 share data, and \c s3
+ and \c s4 share data.
+ \snippet doc/src/snippets/code/src_qt3support_tools_q3deepcopy.cpp 2
+
+ Q3DeepCopy can also provide safety in multithreaded applications
+ that use shared classes. In the example below, the variable \c
+ global_string is used safely since the data contained in \c
+ global_string is always a deep copy. This ensures that all threads
+ get a unique copy of the data, and that any assignments to \c
+ global_string will result in a deep copy.
+
+ \snippet doc/src/snippets/code/src_qt3support_tools_q3deepcopy.cpp 3
+
+ \warning It is the application developer's responsibility to
+ protect the object shared across multiple threads.
+
+ The examples above use QString, which is an implicitly shared
+ class. The behavior of Q3DeepCopy is the same when using explicitly
+ shared classes like QByteArray.
+
+ Currently, Q3DeepCopy works with the following classes:
+ \list
+ \i QMemArray (including subclasses like QByteArray and QCString)
+ \i QMap
+ \i QString
+ \i QValueList (including subclasses like QStringList and QValueStack)
+ \i QValueVector
+ \endlist
+
+ \sa \link threads.html Thread Support in Qt \endlink
+*/
+
+/*!
+ \fn Q3DeepCopy::Q3DeepCopy()
+
+ Constructs an empty instance of type \e T.
+*/
+
+/*!
+ \fn Q3DeepCopy::Q3DeepCopy( const T &t )
+
+ Constructs a deep copy of \a t.
+*/
+
+/*!
+ \fn Q3DeepCopy<T>& Q3DeepCopy::operator=( const T &t )
+
+ Assigns a deep copy of \a t.
+*/
+
+/*!
+ \fn Q3DeepCopy::operator T ()
+
+ Returns a deep copy of the encapsulated data.
+*/
+
+QT_END_NAMESPACE