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diff --git a/doc/src/qcache.qdoc b/doc/src/qcache.qdoc deleted file mode 100644 index 6c88ede..0000000 --- a/doc/src/qcache.qdoc +++ /dev/null @@ -1,244 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). -** Contact: Nokia Corporation (qt-info@nokia.com) -** -** This file is part of the documentation 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 http://www.qtsoftware.com/contact. -** $QT_END_LICENSE$ -** -****************************************************************************/ - -/*! - \class QCache - \brief The QCache class is a template class that provides a cache. - - \ingroup tools - \ingroup shared - \mainclass - \reentrant - - QCache\<Key, T\> defines a cache that stores objects of type T - associated with keys of type Key. For example, here's the - definition of a cache that stores objects of type Employee - associated with an integer key: - - \snippet doc/src/snippets/code/doc_src_qcache.qdoc 0 - - Here's how to insert an object in the cache: - - \snippet doc/src/snippets/code/doc_src_qcache.qdoc 1 - - The advantage of using QCache over some other key-based data - structure (such as QMap or QHash) is that QCache automatically - takes ownership of the objects that are inserted into the cache and - deletes them to make room for new objects, if necessary. When - inserting an object into the cache, you can specify a \e{cost}, - which should bear some approximate relationship to the amount of - memory taken by the object. When the sum of all objects' costs - (totalCost()) exceeds the cache's limit (maxCost()), QCache starts - deleting objects in the cache to keep under the limit, starting with - less recently accessed objects. - - By default, QCache's maxCost() is 100. You can specify a - different value in the QCache constructor: - - \snippet doc/src/snippets/code/doc_src_qcache.qdoc 2 - - Each time you call insert(), you can specify a cost as third - argument (after the key and a pointer to the object to insert). - After the call, the inserted object is owned by the QCache, which - may delete it at any time to make room for other objects. - - To look up objects in the cache, use object() or - operator[](). This function looks up an object by its key, and - returns either a pointer to the cached object (which is owned by - the cache) or 0. - - If you want to remove an object from the cache for a particular key, - call remove(). This will also delete the object. If you want to - remove an object from the cache without the QCache deleting it, use - take(). - - \sa QPixmapCache, QHash, QMap -*/ - -/*! \fn QCache::QCache(int maxCost = 100) - - Constructs a cache whose contents will never have a total cost - greater than \a maxCost. -*/ - -/*! \fn QCache::~QCache() - - Destroys the cache. Deletes all the objects in the cache. -*/ - -/*! \fn int QCache::maxCost() const - - Returns the maximum allowed total cost of the cache. - - \sa setMaxCost(), totalCost() -*/ - -/*! \fn void QCache::setMaxCost(int cost) - - Sets the maximum allowed total cost of the cache to \a cost. If - the current total cost is greater than \a cost, some objects are - deleted immediately. - - \sa maxCost(), totalCost() -*/ - -/*! \fn int QCache::totalCost() const - - Returns the total cost of the objects in the cache. - - This value is normally below maxCost(), but QCache makes an - exception for Qt's \l{implicitly shared} classes. If a cached - object shares its internal data with another instance, QCache may - keep the object lying around, possibly contributing to making - totalCost() larger than maxCost(). - - \sa setMaxCost() -*/ - -/*! \fn int QCache::size() const - - Returns the number of objects in the cache. - - \sa isEmpty() -*/ - -/*! \fn int QCache::count() const - - Same as size(). -*/ - -/*! \fn bool QCache::isEmpty() const - - Returns true if the cache contains no objects; otherwise - returns false. - - \sa size() -*/ - -/*! \fn QList<Key> QCache::keys() const - - Returns a list of the keys in the cache. -*/ - -/*! \fn void QCache::clear(); - - Deletes all the objects in the cache. - - \sa remove(), take() -*/ - - -/*! \fn bool QCache::insert(const Key &key, T *object, int cost = 1) - - Inserts \a object into the cache with key \a key and - associated cost \a cost. Any object with the same key already in - the cache will be removed. - - After this call, \a object is owned by the QCache and may be - deleted at any time. In particular, if \a cost is greater than - maxCost(), the object will be deleted immediately. - - The function returns true if the object was inserted into the - cache; otherwise it returns false. - - \sa take(), remove() -*/ - -/*! \fn T *QCache::object(const Key &key) const - - Returns the object associated with key \a key, or 0 if the key does - not exist in the cache. - - \warning The returned object is owned by QCache and may be - deleted at any time. - - \sa take(), remove() -*/ - -/*! \fn bool QCache::contains(const Key &key) const - - Returns true if the cache contains an object associated with key \a - key; otherwise returns false. - - \sa take(), remove() -*/ - -/*! \fn T *QCache::operator[](const Key &key) const - - Returns the object associated with key \a key, or 0 if the key does - not exist in the cache. - - This is the same as object(). - - \warning The returned object is owned by QCache and may be - deleted at any time. -*/ - -/*! \fn bool QCache::remove(const Key &key) - - Deletes the object associated with key \a key. Returns true if the - object was found in the cache; otherwise returns false. - - \sa take(), clear() -*/ - -/*! \fn T *QCache::take(const Key &key) - - Takes the object associated with key \a key out of the cache - without deleting it. Returns a pointer to the object taken out, or - 0 if the key does not exist in the cache. - - The ownership of the returned object is passed to the caller. - - \sa remove() -*/ - -/*! - \fn QCache::QCache(int maxCost, int dummy) - - Use QCache(int) instead. -*/ - -/*! - \fn T *QCache::find(const Key &key) const - - Use object() instead. -*/ |