/**************************************************************************** ** ** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies). ** Contact: http://www.qt-project.org/legal ** ** This file is part of the QtXmlPatterns module of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:LGPL$ ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and Digia. For licensing terms and ** conditions see http://qt.digia.com/licensing. For further information ** use the contact form at http://qt.digia.com/contact-us. ** ** 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, Digia gives you certain additional ** rights. These rights are described in the Digia 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. ** ** ** $QT_END_LICENSE$ ** ****************************************************************************/ // // W A R N I N G // ------------- // // This file is not part of the Qt API. It exists purely as an // implementation detail. This header file may change from version to // version without notice, or even be removed. // // We mean it. #ifndef Patternist_CachingIterator_H #define Patternist_CachingIterator_H #include #include #include #include QT_BEGIN_NAMESPACE namespace QPatternist { /** * @short An QAbstractXmlForwardIterator that gets its item from a cache unless its empty, in * which case it continues to populate the cache as well as deliver on its * own from a source QAbstractXmlForwardIterator. * * @author Frans Englich * @ingroup Patternist_iterators */ class CachingIterator : public Item::Iterator { public: /** * We always use the same cache cell so why don't we use it directly, * instead of passing the slot and ItemSequenceCacheCell::Vector to * this class? Because the GenericDynamicContext might decide to resize * the vector and that would invalidate the reference. * * We intentionally pass in a non-const reference here. */ CachingIterator(ItemSequenceCacheCell::Vector &cacheCells, const VariableSlotID slot, const DynamicContext::Ptr &context); virtual Item next(); virtual Item current() const; virtual xsInteger position() const; virtual Item::Iterator::Ptr copy() const; private: Item m_current; xsInteger m_position; /** * This variable cannot be called m_slot, because * /usr/include/sys/sysmacros.h on hpuxi-acc defines it. */ const VariableSlotID m_varSlot; /** * We don't use the context. We only keep a reference such that it * doesn't get deleted, and m_cacheCells starts to dangle. */ const DynamicContext::Ptr m_context; /** * We intentionally store a reference here such that we are able to * modify the item. */ ItemSequenceCacheCell::Vector &m_cacheCells; /** * Whether this CachingIterator is delivering items from * m_cacheCell.cacheItems or from m_cacheCell.sourceIterator. */ bool m_usingCache; }; } QT_END_NAMESPACE #endif