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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 QtXmlPatterns 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 <QVector>
+
+#include "qabstractxmlnodemodel_p.h"
+#include "qabstractxmlreceiver.h"
+#include "qcommonvalues_p.h"
+#include "qemptyiterator_p.h"
+#include "qitemmappingiterator_p.h"
+#include "qitem_p.h"
+#include "qnamespaceresolver_p.h"
+#include "qsequencemappingiterator_p.h"
+#include "qsingletoniterator_p.h"
+
+#include "qabstractxmlnodemodel.h"
+
+QT_BEGIN_NAMESPACE
+
+using namespace QPatternist;
+
+typedef QExplicitlySharedDataPointer<QAbstractXmlForwardIterator<QXmlNodeModelIndex> > QXmlNodeModelIndexIteratorPointer;
+
+/**
+ * @file
+ * @short Contains the implementation of QAbstractXmlNodeModel.
+ */
+
+bool QAbstractXmlNodeModel::isIgnorableInDeepEqual(const QXmlNodeModelIndex &n)
+{
+ Q_ASSERT(!n.isNull());
+ const QXmlNodeModelIndex::NodeKind nk = n.kind();
+ return nk == QXmlNodeModelIndex::ProcessingInstruction ||
+ nk == QXmlNodeModelIndex::Comment;
+}
+
+
+/*!
+ \class QAbstractXmlNodeModel
+ \brief The QAbstractXmlNodeModel class is an abstract base class for modeling non-XML data to look like XML for QXmlQuery.
+ \threadsafe
+ \since 4.4
+ \ingroup xml-tools
+
+ The QAbstractXmlNodeModel specifies the interface that a node model
+ must implement for that node model be accessible to the query engine
+ for processing XQuery queries. A node model represents data as a
+ structure that can be queried as if the data were XML.
+
+ The node model represented by a subclass of QAbstractXmlNodeModel is
+ meant to be accessed by the QtXmlPatterns query engine. If the API
+ seems a little strange in a few places, it is because the member
+ functions are called by the query engine as it evaluates an
+ XQuery. They aren't meant to be used programatically.
+
+ \section1 Usage
+
+ QAbstractXmlNodeModel bridges the gap between the arbitrary structure
+ of the non-XML data to be queried and the well-defined structure of
+ XML data understood by QXmlQuery.
+
+ Consider a chemistry application that reads the file \c
+ chemistryData, which contains non-XML data that represents a
+ chemical structure composed of molecules and atoms. The application
+ will query this chemistry data with an XQuery it reads from file \c
+ queryFile. We write a custom subclass of QAbstractXmlNodeModel (\c
+ ChemistryNodeModel) that reads \c chemistryData and builds a data
+ structure, perhaps composed of objects of our own classes \c
+ molecule and \c atom. Clearly, this data structure is not XML. Our
+ custom subclass will know how to traverse this non-XML structure and
+ present it through the \l
+ {http://www.w3.org/TR/xpath-datamodel/}{XPath Data Model interface}.
+
+ \snippet doc/src/snippets/code/src_xmlpatterns_api_qabstractxmlnodemodel.cpp 1
+
+ The application first creates an instance of QXmlQuery and calls \l
+ {QXmlQuery::setQuery()}{setQuery()} to read \c queryFile containing
+ the XQuery we want to run. Then it creates an instance of our custom
+ node model class, \c ChemistryNodeModel, which is a subclass of
+ QAbstractXmlNodeModel. Its constructor is called with the \l
+ {QXmlNamePool} {name pool} obtained from our QXmlQuery, and with the
+ \c chemistryFile containing the structure of molecules and atoms to
+ be queried. The \l {QXmlNamePool} {name pool} is required because
+ our custom node model has the member function \l
+ {QAbstractXmlNodeModel::name()} {name()}, which returns the \l
+ {QXmlName} {name} of any node in the model. The \l {QXmlQuery}
+ {query} and the custom node model must use the same name pool for
+ constructing these \l {QXmlName} {names}. The constructor would then
+ read \c chemistryFile and build the custom node model structure.
+
+ To connect the \c query to the custom node model, we must bind a
+ variable name used in the query to a node in the model. The variable
+ can then be used in the query as a starting node. First, an \l
+ {QXmlNodeModelIndex} {index} for the desired starting node is
+ retrieved by calling QAbstractXmlNodeModel::createIndex(). Then the
+ index is bound to a variable name, in this case \c queryRoot, by
+ passing the name and the index to QXmlQuery::bindVariable(). The
+ query can then use a variable reference \c $queryRoot to refer to
+ the starting node. Note that if the \l {QXmlQuery} {query} uses
+ multiple variable references, a call to QXmlQuery::bindVariable()
+ is required to bind each different variable name to a node in the
+ model.
+
+ The query is executed when the application calls one of the
+ QXmlQuery evaluation functions. The application uses
+ QXmlQuery::evaluateTo(QAbstractXmlReceiver *), because it then uses
+ a \l {QXmlSerializer} {serializer} to out the query result as XML to
+ \c stdout. We could have used QXmlQuery::evaluateTo(QXmlResultItems
+ *) to get a list of result items, or
+ QXmlQuery::evaluateTo(QStringList *) if the query evaluated to a
+ sequence of \c {xs:string} values.
+
+ During query execution, the engine iterates over the node model
+ using nextFromSimpleAxis() to get the \l {QXmlNodeModelIndex}
+ {index} of the next node to be visited. The engine can get the name
+ of a node by calling name() with the node's \l {QXmlNodeModelIndex}
+ {index}. stringValue(), baseUri(), documentUri() and kind() are also
+ called as needed with a node \l {QXmlNodeModelIndex} {index}.
+
+ The example demonstrates the standard pattern for using a subclass
+ of QAbstractXmlNodeModel in combination with QXmlQuery to perform
+ an XQuery.
+
+ \list 1
+
+ \o Instantiate QXmlQuery and give it the XQuery to be run;
+
+ \o Instantiate a subclass of QAbstractXmlNodeModel or
+ QSimpleXmlNodeModel;
+
+ \o Retrieve a QXmlNodeModelIndex for the node in the model where
+ the QXmlQuery should start the query;
+
+ \o Use QXmlQuery::bindVariable() to bind the QXmlNodeModelIndex
+ to \c {$variable name};
+
+ \o Call one of the QXmlQuery evaluation functions to run the
+ query.
+
+ \endlist
+
+ \section1 Subclassing
+
+ Because the \l {http://www.w3.org/TR/xpath-datamodel/}{XPath Data Model
+ interface} presented by QAbstractXmlNodeModel allows QXmlQuery to
+ operate on non-XML data as if it were XML, implementing subclasses
+ of QAbstractXmlNodeModel can involve a significant amount of
+ work. The QSimpleXmlNodeModel class is provided to simplify the
+ implementation for many common use cases.
+
+ \section1 Thread Safety
+
+ Because the node model can be accessed concurrently by threads in
+ the QtXmlPatterns module, subclasses of QAbstractXmlNodeModel must
+ be written to be \l{Thread Support in Qt#Reentrancy and Thread-Safety}
+ {thread-safe}.
+ Classes that simplify implementing thread-safety include QReadLocker
+ and QWriteLocker.
+
+ See the example \l{File System Example} for a demonstration.
+ */
+
+/*!
+ \enum QXmlNodeModelIndex::Constants
+
+ \value ForwardAxis All forward axes include this flag.
+ \value ReverseAxis All reverse axes include this flag.
+ */
+
+/*!
+ \enum QXmlNodeModelIndex::DocumentOrder
+
+ Identifies the specific node comparison operator that should be
+ used.
+
+ \value Precedes Signifies the \c \<\< operator. Test whether the
+ first operand precedes the second in the document.
+
+ \value Follows Signifies the \c \>\> operator. Test whether the
+ first operand follows the second in the document.
+
+ \value Is Signifies the \c is operator. Test whether two nodes have
+ the same node identity.
+ */
+
+/*!
+ \enum QAbstractXmlNodeModel::SimpleAxis
+
+ Four axes that each contain one node only.
+
+ \value Parent The parent of the context node
+ \value FirstChild The first child of the context node
+ \value PreviousSibling The previous child of the context node
+ \value NextSibling The next child of the context node
+*/
+
+/*!
+ \enum QXmlNodeModelIndex::Axis
+ \internal
+
+ Identify the axes emanating from a node.
+
+ The axes AxisChild, AxisDescendant, AxisAttribute, AxisSelf,
+ AxisDescendantOrSelf, AxisFollowingSibling, and AxisFollowing are
+ forward axes.
+
+ The axes AxisParent, AxisAncestor, AxisPrecedingSibling,
+ AxisPreceding and AxisAncestorOrSelf are reverse axes.
+
+ \sa {http://www.w3.org/TR/xquery/#axes}{XQuery 1.0: An XML Query Language, 3.2.1.1 Axes}
+
+ \value AxisChild The \c child axis.
+
+ \value AxisDescendant The \c descendant axis.
+
+ \value AxisAttribute The \c attribute axis. Note: There
+ is a node kind named \c{Attribute}.
+
+ \value AxisSelf The \c self axis.
+
+ \value AxisDescendantOrSelf The \c descendant-or-self axis.
+
+ \value AxisFollowingSibling The \c following-sibling axis.
+
+ \value AxisNamespace The \c namespace axis. Note: Does
+ not exist in XQuery; deprecated in
+ XPath 2.0 (optionally supported);
+ mandatory in XPath 1.0.
+
+ \value AxisFollowing The \c following axis.
+
+ \value AxisParent The \c parent axis.
+
+ \value AxisAncestor The \c ancestor axis.
+
+ \value AxisPrecedingSibling The \c preceding-sibling axis.
+
+ \value AxisPreceding The \c preceding axis.
+
+ \value AxisAncestorOrSelf The \c ancestor-or-self axis.
+*/
+
+using namespace QPatternist;
+
+/*!
+ Default constructor.
+ */
+QAbstractXmlNodeModel::QAbstractXmlNodeModel() : d_ptr(0)
+{
+}
+
+/*!
+ \internal
+
+ Takes the d-pointer.
+
+ */
+QAbstractXmlNodeModel::QAbstractXmlNodeModel(QAbstractXmlNodeModelPrivate *d) : d_ptr(d)
+{
+}
+
+/*!
+ Destructor.
+ */
+QAbstractXmlNodeModel::~QAbstractXmlNodeModel()
+{
+ delete d_ptr;
+}
+
+/*!
+ \typedef QAbstractXmlNodeModel::List
+
+ A \l{QList}{list} of \l{QExplicitlySharedDataPointer} {smart
+ pointers} to instances of QAbstractXmlNodeModel.
+
+ \sa QExplicitlySharedDataPointer
+ */
+
+/*!
+ \typedef QAbstractXmlNodeModel::Ptr
+
+ A \l {QExplicitlySharedDataPointer} {smart pointer} to an
+ instance of QAbstractXmlNodeModel.
+
+ \sa QExplicitlySharedDataPointer
+ */
+
+/*!
+ \fn QUrl QAbstractXmlNodeModel::baseUri(const QXmlNodeModelIndex &n) const
+
+ Returns the base URI for the node whose index is \a n. The caller
+ guarantees that \a n is not \c null and that it belongs to a node
+ in this node model.
+
+ The base URI of a node can be extracted using the \c fn:base-uri()
+ function. The base URI is typically used for resolving relative URIs
+ that appear in the node or its children. It is conformant to just
+ return the document URI, although that might not properly reflect
+ the underlying data.
+
+ This function maps to the \c dm:base-uri accessor, which returns
+ a base URI according to the following:
+
+ \list
+
+ \o For document nodes, the base URI and the document URI are the same.
+
+ \o For elements, the base URI is the URI appearing in the element's
+ \c xml:base attribute, if present, or it is resolved to the
+ parent element's base URI.
+
+ \o Namespace nodes have no base URI.
+
+ \o The base URI for a processing instruction, comment, attribute,
+ or text node is the base URI of the node's parent element.
+
+ \endlist
+
+ The implementation guarantees to return a valid QUrl, or a default
+ constructed QUrl. If a node has no base URI, as in the case where a
+ comment has no parent, a default constructed QUrl is returned.
+
+ \sa {http://www.w3.org/TR/xpath-datamodel/#dm-base-uri}{XQuery 1.0 and XPath 2.0 Data Model (XDM), 5.2 base-uri Accessor}
+ */
+
+/*!
+ \fn QUrl QAbstractXmlNodeModel::documentUri(const QXmlNodeModelIndex &n) const
+
+ Returns the document URI of \a n. The document URI identifies the
+ resource which is the document. For example, the document could be a
+ regular file, e.g., \c{file:/}, or it could be the \c{http://} URL of
+ the location of a file. The document URI is used for resolving URIs
+ and to simply know where the document is.
+
+ If the node model maps to a URI in a natural way, return that URI.
+ Otherwise, return the company or product URI. The document URI can
+ be any URI as long as its valid and absolute.
+
+ The caller guarantees that \a n is not \c null and that it belongs
+ to this QAbstractXmlNodeModel.
+
+ This function maps to the \c dm:document-uri accessor, which
+ returns a document URI according to the following:
+
+ \list
+
+ \o If \a n is a document node, return an absolute QUrl containing
+ the document URI, or a default constructed QUrl. The latter
+ signals that no document URI is available for the document node.
+
+ \o For all other nodes, return a default constructed QUrl.
+
+ \endlist
+
+ \sa {http://www.w3.org/TR/xpath-datamodel/#dm-document-uri}{XQuery 1.0 and XPath 2.0 Data Model (XDM), 5.4 document-uri Accessor}
+ \sa QUrl::isValid(), QUrl::isRelative()
+ */
+
+/*
+### Qt 5:
+
+Add the function:
+
+ virtual QSourceLocation sourceLocation(const QXmlNodeModelIndex &nodeIndex) const = 0;
+
+Such that the data model can communicate back source locations.
+ */
+
+/*!
+ \fn QXmlNodeModelIndex::NodeKind QAbstractXmlNodeModel::kind(const QXmlNodeModelIndex &ni) const
+
+ Returns a value indicating the kind of node identified by \a ni.
+ The caller guarantees that \a ni is not null and that it identifies
+ a node in this node model. This function maps to the \c
+ dm:node-kind() accessor.
+
+ \sa {http://www.w3.org/TR/xpath-datamodel/#dm-node-kind}{XQuery 1.0 and XPath 2.0 Data Model (XDM), 5.10 node-kind Accessor}
+ */
+
+/*!
+ \fn QXmlNodeModelIndex::DocumentOrder QAbstractXmlNodeModel::compareOrder(const QXmlNodeModelIndex &ni1, const QXmlNodeModelIndex &ni2) const
+
+ This function returns the relative document order for the
+ nodes indexed by \a ni1 and \a ni2. It is used for the \c Is
+ operator and for sorting nodes in document order.
+
+ The caller guarantees that \a ni1 and \a ni2 are not \c null and
+ that both identify nodes in this node model.
+
+ If \a ni1 is identical to \a ni2, QXmlNodeModelIndex::Is is returned.
+ If \a ni1 precedes \a ni2 in document order, QXmlNodeModelIndex::Precedes
+ is returned. If \a ni1 follows \a ni2 in document order,
+ QXmlNodeModelIndex::Follows is returned.
+
+ \sa {http://www.w3.org/TR/xpath-datamodel/#document-order}{XQuery 1.0 and XPath 2.0 Data Model (XDM), 2.4 Document Order}
+ */
+
+/*!
+ \fn QXmlNodeModelIndex QAbstractXmlNodeModel::root(const QXmlNodeModelIndex &n) const
+
+ Returns the root node of the tree that contains the node whose index
+ is \a n. The caller guarantees that \a n is not \c null and that it
+ identifies a node in this node model.
+
+ If \a n identifies a node that is a direct child of the root,
+ parent() would return the same QXmlNodeModelIndex returned by
+ this function.
+ */
+
+namespace QPatternist
+{
+ class MergeIterator
+ {
+ public:
+ inline MergeIterator()
+ {
+ }
+
+ inline
+ QXmlNodeModelIndexIteratorPointer
+ mapToSequence(const QXmlNodeModelIndexIteratorPointer &it,
+ const DynamicContext::Ptr &) const
+ {
+ return it;
+ }
+
+ private:
+ Q_DISABLE_COPY(MergeIterator)
+ };
+
+ static const MergeIterator mergeIterator;
+
+ /**
+ * One might wonder, why not use makeVectorIterator() directly on a QVector
+ * with iterators?
+ *
+ * A problem emerges QAbstractXmlForwardIterator::copy(). All "meta
+ * iterators" that contain other iterators and so forth, propagate the
+ * copy() call such that all involved iterators are copied. However, if we
+ * have a ListIterator of iterators it isn't aware of that it contains
+ * iterators. Hence, we have this class which is specialized(not in the
+ * template sense) on iterators, and hence copies them appropriately.
+ */
+ class IteratorVector : public ListIterator<QXmlNodeModelIndexIteratorPointer, QVector<QXmlNodeModelIndexIteratorPointer> >
+ {
+ typedef QVector<QXmlNodeModelIndexIteratorPointer> ItVector;
+ public:
+ typedef QAbstractXmlForwardIterator<QXmlNodeModelIndexIteratorPointer>::Ptr Ptr;
+
+ IteratorVector(const ItVector &in) : ListIterator<QXmlNodeModelIndexIteratorPointer, QVector<QXmlNodeModelIndexIteratorPointer> >(in)
+ {
+ }
+
+ virtual QAbstractXmlForwardIterator<QXmlNodeModelIndexIteratorPointer>::Ptr copy() const
+ {
+ ItVector result;
+
+ for(int i = 0; i < m_list.count(); ++i)
+ result.append(m_list.at(i)->copy());
+
+ return Ptr(new IteratorVector(result));
+ }
+ };
+}
+
+/*!
+ \internal
+ This function is not a private member of QAbstractXmlNodeModel
+ because it would be messy to forward declare the required types.
+*/
+static inline QXmlNodeModelIndexIteratorPointer mergeIterators(const QXmlNodeModelIndex &node,
+ const QXmlNodeModelIndexIteratorPointer &it2)
+{
+ QVector<QXmlNodeModelIndexIteratorPointer> iterators;
+ iterators.append(makeSingletonIterator(node));
+ iterators.append(it2);
+
+ return makeSequenceMappingIterator<QXmlNodeModelIndex>(&mergeIterator,
+ IteratorVector::Ptr(new IteratorVector(iterators)),
+ DynamicContext::Ptr());
+}
+
+inline QAbstractXmlForwardIterator<QXmlNodeModelIndex>::Ptr
+QAbstractXmlNodeModel::mapToSequence(const QXmlNodeModelIndex &ni,
+ const DynamicContext::Ptr &) const
+{
+ Q_ASSERT(!ni.isNull());
+ /* Since we pass in this here, mapToSequence is used recursively. */
+ return mergeIterators(ni, makeSequenceMappingIterator<QXmlNodeModelIndex>(this,
+ ni.iterate(QXmlNodeModelIndex::AxisChild),
+ DynamicContext::Ptr()));
+}
+
+/*!
+ \fn QVector<QXmlNodeModelIndex> QAbstractXmlNodeModel::attributes(const QXmlNodeModelIndex &element) const
+
+ Returns the attributes of \a element. The caller guarantees
+ that \a element is an element in this node model.
+ */
+
+/*!
+ \internal
+
+ Performs navigation, starting from \a ni, by returning an
+ QAbstractXmlForwardIterator that returns nodes the \a axis emanating
+ from \a ni.
+
+ The implementation returns the nodes on the \a axis, without
+ duplicates and in \a axis order. This means that if \a axis is a
+ reverse axis, which is the case for the \c parent, \c ancestor, \c
+ ancestor-or-self, \c preceding, and \c preceding-sibling, the nodes
+ are delivered in reverse document order. Otherwise the nodes are
+ delivered in document order.
+
+ The implementor guarantees that the nodes delivered for the axes are
+ consistent with the XPath Data Model. This just implies common
+ sense, e.g., The child axis for a comment node can't contain any
+ children; a document node can't be a child of an element, etc.
+ Attributes aren't considered children of an element, but are only
+ available on AxisAttribute.
+
+ The value past in \a axis is not guaranteed based on what is used in
+ a query. QtXmlPatterns may call this function arbitrarily with any
+ value for \a axis. This is because QtXmlPatterns may rewrite queries
+ to be more efficient, using axes in different ways from the original
+ query.
+
+ QAbstractXmlNodeModel::Axis has a good overview of the axes and what
+ they select.
+
+ The caller guarantees that \a ni is not \c null and that it belongs
+ to this QAbstractXmlNodeModel instance.
+
+ Implementing iterate() can involve significant work, since it
+ requires different iterators for all the axes used. In the worst
+ case, it could require writing as many QAbstractXmlForwardIterator
+ subclasses as there are axes, but the number can often be reduced
+ with clever use of lists and template classes. It is better to use
+ or subclass QSimpleXmlNodeModel, which makes it easier to write the
+ node navigation code without loss of efficiency or flexibility.
+
+ \sa QSimpleXmlNodeModel
+ \sa QXmlNodeModelIndex::Axis
+ \sa {http://www.w3.org/TR/xquery/#axes}{XQuery 1.0: An XML Query Language, 3.2.1.1 Axes}
+ \sa {http://www.w3.org/TR/xpath-datamodel/}{W3CXQuery 1.0 and XPath 2.0 Data Model (XDM)}
+ */
+QExplicitlySharedDataPointer<QAbstractXmlForwardIterator<QXmlNodeModelIndex> >
+QAbstractXmlNodeModel::iterate(const QXmlNodeModelIndex &ni,
+ QXmlNodeModelIndex::Axis axis) const
+{
+ /* Returns iterators that track state and calls nextFromSimpleAxis()
+ * iteratively. Typically, when sub-classing QSimpleXmlNodeModel,
+ * you don't reimplement this function, but instead implement
+ * nextFromSimpleAxis(). */
+
+ switch(axis)
+ {
+ case QXmlNodeModelIndex::AxisSelf:
+ return makeSingletonIterator(ni);
+ case QXmlNodeModelIndex::AxisParent:
+ {
+ if(kind(ni) == QXmlNodeModelIndex::Document)
+ return makeEmptyIterator<QXmlNodeModelIndex>();
+ else
+ return makeSingletonIterator(nextFromSimpleAxis(Parent, ni));
+ }
+ case QXmlNodeModelIndex::AxisNamespace:
+ return makeEmptyIterator<QXmlNodeModelIndex>();
+ case QXmlNodeModelIndex::AxisAncestor:
+ {
+ QList<QXmlNodeModelIndex> ancestors;
+ QXmlNodeModelIndex ancestor = nextFromSimpleAxis(Parent, ni);
+
+ while(!ancestor.isNull())
+ {
+ ancestors.append(ancestor);
+ ancestor = nextFromSimpleAxis(Parent, ancestor);
+ }
+
+ return makeListIterator(ancestors);
+ }
+ case QXmlNodeModelIndex::AxisAncestorOrSelf:
+ {
+ QList<QXmlNodeModelIndex> ancestors;
+ ancestors.append(ni);
+ QXmlNodeModelIndex ancestor = nextFromSimpleAxis(Parent, ni);
+
+ while(!ancestor.isNull())
+ {
+ ancestors.append(ancestor);
+ ancestor = nextFromSimpleAxis(Parent, ancestor);
+ }
+
+ return makeListIterator(ancestors);
+ }
+ case QXmlNodeModelIndex::AxisPrecedingSibling:
+ {
+ QList<QXmlNodeModelIndex> preceding;
+ QXmlNodeModelIndex sibling = nextFromSimpleAxis(PreviousSibling, ni);
+
+ while(!sibling.isNull())
+ {
+ preceding.append(sibling);
+ sibling = nextFromSimpleAxis(PreviousSibling, sibling);
+ }
+
+ return makeListIterator(preceding);
+ }
+ case QXmlNodeModelIndex::AxisFollowingSibling:
+ {
+ QList<QXmlNodeModelIndex> preceding;
+ QXmlNodeModelIndex sibling = nextFromSimpleAxis(NextSibling, ni);
+
+ while(!sibling.isNull())
+ {
+ preceding.append(sibling);
+ sibling = nextFromSimpleAxis(NextSibling, sibling);
+ }
+
+ return makeListIterator(preceding);
+ }
+ case QXmlNodeModelIndex::AxisChildOrTop:
+ {
+ if(nextFromSimpleAxis(Parent, ni).isNull())
+ {
+ switch(kind(ni))
+ {
+ case QXmlNodeModelIndex::Comment:
+ /* Fallthrough. */
+ case QXmlNodeModelIndex::ProcessingInstruction:
+ /* Fallthrough. */
+ case QXmlNodeModelIndex::Element:
+ /* Fallthrough. */
+ case QXmlNodeModelIndex::Text:
+ return makeSingletonIterator(ni);
+ case QXmlNodeModelIndex::Attribute:
+ /* Fallthrough. */
+ case QXmlNodeModelIndex::Document:
+ /* Fallthrough. */
+ case QXmlNodeModelIndex::Namespace:
+ /* Do nothing. */;
+ }
+ }
+
+ /* Else, fallthrough to AxisChild. */
+ }
+ case QXmlNodeModelIndex::AxisChild:
+ {
+ QList<QXmlNodeModelIndex> children;
+ QXmlNodeModelIndex child = nextFromSimpleAxis(FirstChild, ni);
+
+ while(!child.isNull())
+ {
+ children.append(child);
+ child = nextFromSimpleAxis(NextSibling, child);
+ }
+
+ return makeListIterator(children);
+ }
+ case QXmlNodeModelIndex::AxisDescendant:
+ {
+ return makeSequenceMappingIterator<QXmlNodeModelIndex>(this,
+ ni.iterate(QXmlNodeModelIndex::AxisChild),
+ DynamicContext::Ptr());
+ }
+ case QXmlNodeModelIndex::AxisAttributeOrTop:
+ {
+ if(kind(ni) == QXmlNodeModelIndex::Attribute && nextFromSimpleAxis(Parent, ni).isNull())
+ return makeSingletonIterator(ni);
+
+ /* Else, fallthrough to AxisAttribute. */
+ }
+ case QXmlNodeModelIndex::AxisAttribute:
+ return makeVectorIterator(attributes(ni));
+ case QXmlNodeModelIndex::AxisDescendantOrSelf:
+ return mergeIterators(ni, iterate(ni, QXmlNodeModelIndex::AxisDescendant));
+ case QXmlNodeModelIndex::AxisFollowing:
+ /* Fallthrough. */
+ case QXmlNodeModelIndex::AxisPreceding:
+ {
+ /* We walk up along the ancestors, and for each parent, we grab its preceding/following
+ * siblings, and evaluate the descendant axis. The descendant axes gets added
+ * to a list and we then merge those iterators. */
+ QVector<QXmlNodeModelIndexIteratorPointer> descendantIterators;
+
+ QXmlNodeModelIndex current(ni);
+ while(!current.isNull())
+ {
+ QXmlNodeModelIndex candidate(nextFromSimpleAxis(axis == QXmlNodeModelIndex::AxisPreceding ? PreviousSibling : NextSibling, current));
+ if(candidate.isNull())
+ {
+ /* current is an ancestor. We don't want it, so next iteration we
+ * will grab its preceding sibling. */
+ current = nextFromSimpleAxis(Parent, current);
+ }
+ else
+ {
+ current = candidate;
+ descendantIterators.append(iterate(current, QXmlNodeModelIndex::AxisDescendantOrSelf)->toReversed());
+ }
+ }
+
+ return makeSequenceMappingIterator<QXmlNodeModelIndex>(&mergeIterator,
+ IteratorVector::Ptr(new IteratorVector(descendantIterators)),
+ DynamicContext::Ptr());
+ }
+ }
+
+ Q_ASSERT_X(false, Q_FUNC_INFO, "Unknown axis, internal error.");
+ return makeEmptyIterator<QXmlNodeModelIndex>();
+}
+
+/*!
+ \fn QXmlNodeModelIndex QAbstractXmlNodeModel::nextFromSimpleAxis(SimpleAxis axis, const QXmlNodeModelIndex &origin) const
+
+ When QtXmlPatterns evaluate path expressions, it emulate them through a
+ combination of calls with QSimpleXmlNodeModel::SimpleAxis values. Therefore,
+ the implementation of this function must return the node, if any, that
+ appears on the \a axis emanating from the \a origin.
+
+ If no such node is available, a default constructed
+ QXmlNodeModelIndex is returned.
+
+ QSimpleXmlNodeModel eliminates the need to handle redundant corner
+ cases by guaranteeing that it will never ask for:
+
+ \list
+ \o Children or siblings for attributes.
+ \o Children for comments, processing instructions, and text nodes.
+ \o Siblings or parents for document nodes.
+ \endlist
+
+ A typical implementation performs a \c switch on the value of \a
+ axis:
+
+ \code
+ QXmlNodeModelIndex MyTreeModel::nextFromSimpleAxis(SimpleAxis axis, const QXmlNodeModelIndex &origin) const
+ {
+ // Convert the QXmlNodeModelIndex to a value that is specific to what we represent.
+ const MyValue value = toMyValue(ni);
+
+ switch(axis)
+ {
+ case Parent:
+ return toNodeIndex(value.parent());
+ case FirstChild:
+ case PreviousSibling:
+ case NextSibling:
+ // and so on
+ }
+ }
+ \endcode
+
+ */
+
+/*!
+ \fn QXmlNodeModelIndex QAbstractXmlNodeModel::createIndex(qint64 data) const
+
+ Creates a node index with \a data as its internal data. \a data is
+ not constrained.
+ */
+
+/*!
+ \fn QXmlNodeModelIndex QAbstractXmlNodeModel::createIndex(void *pointer, qint64 additionalData) const
+
+ Creates a node index with \a pointer and \a additionalData as
+ its internal data.
+
+ What \a pointer and \a additionalData is, is not constrained.
+ */
+
+/*!
+ \fn QXmlNodeModelIndex QAbstractXmlNodeModel::createIndex(qint64 data, qint64 additionalData) const;
+ \overload
+
+ Creates a QXmlNodeModelIndex containing \a data and \a
+ additionalData.
+ */
+
+/*!
+ \fn QXmlName QAbstractXmlNodeModel::name(const QXmlNodeModelIndex &ni) const
+
+ Returns the name of \a ni. The caller guarantees that \a ni is not
+ \c null and that it belongs to this QAbstractXmlNodeModel.
+
+ If a node does not have a name, e.g., comment nodes, a null QXmlName
+ is returned. QXmlNames must be created with the instance of
+ QXmlQuery that is being used for evaluating queries using this
+ QAbstractXmlNodeModel.
+
+ This function maps to the \c dm:node-name() accessor.
+
+ If \a ni is a processing instruction, a QXmlName is returned with
+ the local name as the target name and the namespace URI and prefix
+ both empty.
+
+ \sa {http://www.w3.org/TR/xpath-datamodel/#dm-node-name}{XQuery 1.0 and XPath 2.0 Data Model (XDM), 5.11 node-name Accessor}
+ \sa QXmlName
+ */
+
+/*!
+ \fn QVector<QXmlName> QAbstractXmlNodeModel::namespaceBindings(const QXmlNodeModelIndex &n) const
+
+ Returns the in-scope namespaces of \a n. The caller guarantees that
+ \a n is not \c null and that it belongs to this QAbstractXmlNodeModel.
+
+ This function corresponds to the \c dm:namespace-nodes accessor.
+
+ The returned vector of namespace declarations includes namespaces
+ of the ancestors of \a n.
+
+ The caller guarantees that \a n is an Element that belongs to this
+ QAbstractXmlNodeModel.
+ */
+
+/*!
+ \internal
+ Sends the namespaces declared on \a n to \a receiver.
+
+ As a consequence, no namespaces are sent unless this node is an
+ element and has namespaces declared.
+
+ The caller guarantees that \a n is not \c null and that it belongs
+ to this QAbstractXmlNodeModel instance.
+
+ Note that it is not the namespaces that are in scope on \a n, but
+ only the namespaces that are specifically declared on \a n.
+
+ \a receiver is the receiver that this node is supposed to send its
+ namespaces to. This is guaranteed by the caller to be a valid
+ pointer. \a n is the index of the node whose namespaces are to
+ be sent.
+ */
+void QAbstractXmlNodeModel::sendNamespaces(const QXmlNodeModelIndex &n,
+ QAbstractXmlReceiver *const receiver) const
+{
+ Q_ASSERT(receiver);
+ const QVector<QXmlName> nss(namespaceBindings(n));
+
+ /* This is by far the most common case. */
+ if(nss.isEmpty())
+ return;
+
+ const int len = nss.size();
+ for(int i = 0; i < len; ++i)
+ receiver->namespaceBinding(nss.at(i));
+}
+
+/*!
+ \fn QString QAbstractXmlNodeModel::stringValue(const QXmlNodeModelIndex &n) const
+
+ Returns the string value for node \a n.
+
+ The caller guarantees that \a n is not \c null and that it belong to
+ this QAbstractXmlNodeModel instance.
+
+ This function maps to the \c dm:string-value() accessor, which the
+ specification completely specifies. Here's a summary:
+
+ \list
+
+ \o For processing instructions, the string value is the data
+ section(excluding any whitespace appearing between the name and the
+ data).
+
+ \o For text nodes, the string value equals the text node.
+
+ \o For comments, the content of the comment
+
+ \o For elements, the concatenation of all text nodes that are
+ descendants. Note, this is not only the children, but the
+ childrens' childrens' text nodes, and so forth.
+
+ \o For document nodes, the concatenation of all text nodes in the
+ document.
+
+ \endlist
+
+ \sa {http://www.w3.org/TR/xpath-datamodel/#dm-string-value}{XQuery 1.0 and XPath 2.0 Data Model (XDM), 5.13 string-value Accessor}
+ */
+
+/*!
+ \fn QVariant QAbstractXmlNodeModel::typedValue(const QXmlNodeModelIndex &node) const
+
+ Returns the typed value for node \a node.
+
+ The typed value is an atomic value, which an element or attribute
+ contains.
+
+ The caller guarantees that \a node is either an element or an
+ attribute. The implementor guarantees that the returned QVariant has
+ a value which is supported in XQuery. It cannot be an arbitrary
+ QVariant value. The implementor also guarantees that stringValue()
+ returns a lexical representation of typedValue()(this is guaranteed
+ by QSimpleXmlNodeModel::stringValue()).
+
+ If the return QVariant is a default constructed variant, it signals
+ that \a node has no typed value.
+*/
+
+/*!
+ \internal
+ */
+QPatternist::ItemIteratorPtr QAbstractXmlNodeModel::sequencedTypedValue(const QXmlNodeModelIndex &ni) const
+{
+ const QVariant &candidate = typedValue(ni);
+ if(candidate.isNull())
+ return QPatternist::CommonValues::emptyIterator;
+ else
+ return makeSingletonIterator(AtomicValue::toXDM(candidate));
+}
+
+/*!
+ \internal
+ */
+QPatternist::ItemTypePtr QAbstractXmlNodeModel::type(const QXmlNodeModelIndex &) const
+{
+ Q_ASSERT_X(false, Q_FUNC_INFO,
+ "This function is internal and must not be called.");
+ return QPatternist::ItemTypePtr();
+}
+
+/*!
+ \internal
+
+ Returns the namespace URI on \a ni that corresponds to \a prefix.
+
+ If \a prefix is StandardPrefixes::empty, the namespace URI for the
+ default namespace is returned.
+
+ The default implementation use namespaceBindings(), in a straight
+ forward manner.
+
+ If no namespace exists for \a prefix, NamespaceResolver::NoBinding
+ is returned.
+
+ The caller guarantees to only call this function for element nodes.
+ */
+QXmlName::NamespaceCode QAbstractXmlNodeModel::namespaceForPrefix(const QXmlNodeModelIndex &ni,
+ const QXmlName::PrefixCode prefix) const
+{
+ Q_ASSERT(kind(ni) == QXmlNodeModelIndex::Element);
+
+ const QVector<QXmlName> nbs(namespaceBindings(ni));
+ const int len = nbs.size();
+
+ for(int i = 0; i < len; ++i)
+ {
+ if(nbs.at(i).prefix() == prefix)
+ return nbs.at(i).namespaceURI();
+ }
+
+ return NamespaceResolver::NoBinding;
+}
+
+
+/*!
+ \internal
+
+ Determines whether \a ni1 is deep equal to \a ni2.
+
+ isDeepEqual() is defined as evaluating the expression \c
+ fn:deep-equal($n1, $n2) where \c $n1 is \a ni1 and \c $n1 is \a
+ ni2. This function is associative, meaning the same value is
+ returned regardless of if isDeepEqual() is invoked with \a ni1 as
+ first argument or second. It is guaranteed that \a ni1 and \a ni2
+ are nodes, as opposed to the definition of \c fn:deep-equal().
+
+ Returns true if \a ni1 is deep-equal to \a ni2, otherwise false
+
+ \sa {"http://www.w3.org/TR/xpath-functions/#func-deep-equal"}{XQuery 1.0 and XPath 2.0 Functions and Operators, 15.3.1 fn:deep-equal}
+ */
+bool QAbstractXmlNodeModel::isDeepEqual(const QXmlNodeModelIndex &n1,
+ const QXmlNodeModelIndex &n2) const
+{
+ Q_ASSERT(!n1.isNull());
+ Q_ASSERT(!n2.isNull());
+
+ const QXmlNodeModelIndex::NodeKind nk = n1.kind();
+
+ if(nk != n2.kind())
+ return false;
+
+ if(n1.name() != n2.name())
+ return false;
+
+ switch(nk)
+ {
+ case QXmlNodeModelIndex::Element:
+ {
+ QXmlNodeModelIndexIteratorPointer atts1(n1.iterate(QXmlNodeModelIndex::AxisAttribute));
+ QXmlNodeModelIndex node(atts1->next());
+
+ const QXmlNodeModelIndex::List atts2(n2.iterate(QXmlNodeModelIndex::AxisAttribute)->toList());
+ const QXmlNodeModelIndex::List::const_iterator end(atts2.constEnd());
+
+ while(!node.isNull())
+ {
+ bool equal = false;
+ for(QXmlNodeModelIndex::List::const_iterator it = atts2.constBegin(); it != end; ++it)
+ {
+ if(isDeepEqual(node, (*it)))
+ equal = true;
+ }
+
+ if(!equal)
+ return false;
+
+ node = atts1->next();
+ }
+
+ /* Fallthrough, so we check the children. */
+ }
+ case QXmlNodeModelIndex::Document:
+ {
+ QXmlNodeModelIndexIteratorPointer itn1(n1.iterate(QXmlNodeModelIndex::AxisChild));
+ QXmlNodeModelIndexIteratorPointer itn2(n2.iterate(QXmlNodeModelIndex::AxisChild));
+
+ while(true)
+ {
+ QXmlNodeModelIndex no1(itn1->next());
+ QXmlNodeModelIndex no2(itn2->next());
+
+ while(!no1.isNull() && isIgnorableInDeepEqual(no1))
+ no1 = itn1->next();
+
+ while(!no2.isNull() && isIgnorableInDeepEqual(no2))
+ no2 = itn2->next();
+
+ if(!no1.isNull() && !no2.isNull())
+ {
+ if(!isDeepEqual(no1, no2))
+ return false;
+ }
+ else
+ return no1.isNull() && no2.isNull();
+ }
+
+ return true;
+ }
+ case QXmlNodeModelIndex::Attribute:
+ /* Fallthrough */
+ case QXmlNodeModelIndex::ProcessingInstruction:
+ /* Fallthrough. */
+ case QXmlNodeModelIndex::Text:
+ /* Fallthrough. */
+ case QXmlNodeModelIndex::Comment:
+ return n1.stringValue() == n2.stringValue();
+ case QXmlNodeModelIndex::Namespace:
+ {
+ Q_ASSERT_X(false, Q_FUNC_INFO, "Not implemented");
+ return false;
+ }
+ }
+
+ return false;
+}
+
+/*!
+ \class QXmlItem
+ \reentrant
+ \since 4.4
+ \brief The QXmlItem class contains either an XML node or an atomic value.
+ \ingroup xml-tools
+
+ In XQuery, all expressions evaluate to a sequence of items, where
+ each item is either an XML node or an atomic value. The query in the
+ following snippet evaluates to sequence of five items.
+
+ \quotefile doc/src/snippets/patternist/items.xq
+
+ The five items are: An element, an atomic value (binary data encoded
+ in base64), a date, a float, and an attribute.
+
+ QXmlItem is the class that represents these XQuery items in the
+ QtXmlPatterns API. A non-null instance of QXmlItem is either a node
+ or an atomic value. Calling isNode() or isAtomicValue() tells you
+ which it is. Atomic values are represented elsewhere in the Qt API
+ as instances of QVariant, and an instance of QXmlItem that
+ represents an atomic value can be converted to a QVariant by calling
+ toAtomicValue(). A QXmlItem that wraps a node is represented
+ elsewhere as an instance of QXmlNodeModelIndex. A node QXmlItem can
+ be converted to a QXmlNodeModelIndex by calling toNodeModelIndex().
+
+ A default constructed QXmlItem instance is neither a node nor an
+ atomic value. It is considered null, in which case isNull() returns
+ true.
+
+ An instance of QXmlItem will be left dangling if the
+ \l{QAbstractXmlNodeModel} {XML node model} it
+ refers to is deleted, if it is a QXmlNodeModelIndex.
+ */
+
+/*!
+ \typedef QXmlItem::Iterator
+ A QAbstractXmlForwardIterator over QXmlItem.
+ */
+
+/*!
+ Constructs a null QXmlItem that is neither a node nor an atomic
+ value. isNull() returns true for a default constructed instance.
+ */
+QXmlItem::QXmlItem()
+{
+ m_node.model = 0;
+ m_node.data = 0;
+ m_node.additionalData = 0;
+}
+
+bool QXmlItem::internalIsAtomicValue() const
+{
+ return m_node.model == reinterpret_cast<QAbstractXmlNodeModel *>(~0);
+}
+
+/*!
+ The copy constructor constructs a copy of \a other.
+ */
+QXmlItem::QXmlItem(const QXmlItem &other) : m_node(other.m_node)
+{
+ if(internalIsAtomicValue())
+ m_atomicValue->ref.ref();
+}
+
+/*!
+ Constructs an atomic value QXmlItem with \a atomicValue.
+
+ \sa isAtomicValue()
+ */
+QXmlItem::QXmlItem(const QVariant &atomicValue)
+{
+ if(atomicValue.isNull())
+ {
+ /* Then we behave just like the default constructor. */
+ m_node.model = 0;
+ m_node.data = 0;
+ m_node.additionalData = 0;
+ return;
+ }
+
+ /*
+ We can't assign directly to m_atomicValue, because the
+ temporary will self-destruct before we've ref'd it.
+ */
+ const QPatternist::Item temp(QPatternist::AtomicValue::toXDM(atomicValue));
+
+ if(temp)
+ {
+ temp.asAtomicValue()->ref.ref();
+ m_node.model = reinterpret_cast<const QAbstractXmlNodeModel *>(~0);
+ m_atomicValue = temp.asAtomicValue();
+ }
+ else
+ {
+ m_atomicValue = 0;
+ m_node.model = 0;
+ }
+
+ m_node.additionalData = 0;
+}
+
+/*!
+ Constructs a node QXmlItem that is a copy of \a node.
+
+ \sa isNode()
+ */
+QXmlItem::QXmlItem(const QXmlNodeModelIndex &node) : m_node(node.m_storage)
+{
+}
+
+
+/*!
+ Destructor.
+ */
+QXmlItem::~QXmlItem()
+{
+ if(internalIsAtomicValue() && !m_atomicValue->ref.deref())
+ delete m_atomicValue;
+}
+
+bool QPatternist::NodeIndexStorage::operator!=(const NodeIndexStorage &other) const
+{
+ return data != other.data
+ || additionalData != other.additionalData
+ || model != other.model;
+}
+
+/*!
+ Assigns \a other to \c this.
+ */
+QXmlItem &QXmlItem::operator=(const QXmlItem &other)
+{
+ if(m_node != other.m_node)
+ {
+ if(internalIsAtomicValue() && !m_atomicValue->ref.deref())
+ delete m_atomicValue;
+
+ m_node = other.m_node;
+
+ if(internalIsAtomicValue())
+ m_atomicValue->ref.ref();
+ }
+
+ return *this;
+}
+
+/*!
+ Returns true if this item is a Node. Returns false if it
+ is an atomic value or null.
+
+ \sa isNull(), isAtomicValue()
+ */
+bool QXmlItem::isNode() const
+{
+ return QPatternist::Item::fromPublic(*this).isNode();
+}
+
+/*!
+ Returns true if this item is an atomic value. Returns false
+ if it is a node or null.
+
+ \sa isNull(), isNode()
+ */
+bool QXmlItem::isAtomicValue() const
+{
+ return internalIsAtomicValue();
+}
+
+/*!
+ If this QXmlItem represents an atomic value, it is converted
+ to an appropriate QVariant and returned. If this QXmlItem is
+ not an atomic value, the return value is a default constructed
+ QVariant. You can call isAtomicValue() to test whether the
+ item is an atomic value.
+
+ \sa isAtomicValue()
+ */
+QVariant QXmlItem::toAtomicValue() const
+{
+ if(isAtomicValue())
+ return QPatternist::AtomicValue::toQt(m_atomicValue);
+ else
+ return QVariant();
+}
+
+/*!
+ If this QXmlItem represents a node, it returns the item as a
+ QXmlNodeModelIndex. If this QXmlItem is not a node, the return
+ value is undefined. You can call isNode() to test whether the
+ item is a node.
+
+ \sa isNode()
+ */
+QXmlNodeModelIndex QXmlItem::toNodeModelIndex() const
+{
+ if(isNode())
+ return reinterpret_cast<const QXmlNodeModelIndex &>(m_node);
+ else
+ return QXmlNodeModelIndex();
+}
+
+/*!
+ Returns true if this QXmlItem is neither a node nor an
+ atomic value. Default constructed instances of QXmlItem
+ are null.
+ */
+bool QXmlItem::isNull() const
+{
+ return !m_node.model;
+}
+
+/*!
+ \class QXmlNodeModelIndex
+ \brief The QXmlNodeModelIndex class identifies a node in an XML node model subclassed from QAbstractXmlNodeModel.
+ \reentrant
+ \since 4.4
+ \ingroup xml-tools
+
+ QXmlNodeModelIndex is an index into an \l{QAbstractXmlNodeModel}
+ {XML node model}. It contains:
+
+ \list
+ \o A pointer to an \l{QAbstractXmlNodeModel} {XML node model},
+ which is returned by model(), and
+ \o Some data, which is returned by data(), internalPointer(),
+ and additionalData().
+ \endlist
+
+ Because QXmlNodeModelIndex is intentionally a simple class, it
+ doesn't have member functions for accessing the properties of
+ nodes. For example, it doesn't have functions for getting a
+ node's name or its list of attributes or child nodes. If you find
+ that you need to retrieve this kind of information from your
+ query results, there are two ways to proceed.
+
+ \list
+
+ \o Send the output of your XQuery to an \l{QAbstractXmlReceiver}
+ {XML receiver}, or
+
+ \o Let your XQuery do all the work to produce the desired result.
+
+ \endlist
+
+ The second case is explained by example. Suppose you want to
+ populate a list widget with the values of certain attributes from a
+ set of result elements. You could write an XQuery to return the set
+ of elements, and then you would write the code to iterate over the
+ result elements, get their attributes, and extract the desired
+ string values. But the simpler way is to just augment your XQuery to
+ finding the desired attribute values. Then all you have to do is
+ evaluate the XQuery using the version of QXmlQuery::evaluateTo()
+ that populates a QStringList, which you can send directly to your
+ widget.
+
+ QXmlNodeModelIndex doesn't impose any restrictions on the \c data
+ value an QXmlNodeModelIndex should contain. The meaning of the data
+ left to the associated \l {QAbstractXmlNodeModel} {node model}.
+ Because QXmlNodeModelIndex depends on a particular subclass of
+ QAbstractXmlNodeModel for its existence, the only way you can create
+ an instance of QXmlNodeModelIndex is by asking the node model to
+ create one for you with QAbstractXmlNodeModel::createIndex(). Since
+ that function is protected, it is usually a good ide to write a
+ public function that creates a QXmlNodeModelIndex from arguments that
+ are appropriate for your particular node model.
+
+ A default constructed node index is said to be null, i.e., isNull()
+ returns true.
+
+ QXmlNodeModelIndex and QAbstractXmlNodeModel follow the same design
+ pattern used for QModelIndex and QAbstractItemModel.
+ */
+
+/*!
+ \since 4.4
+ \relates QHash
+
+ Computes a hash key from the QXmlNodeModelIndex \a index, and
+ returns it. This function would be used by QHash if you wanted
+ to build a hash table for instances of QXmlNodeModelIndex.
+
+ The hash is computed on QXmlNodeModelIndex::data(),
+ QXmlNodeModelIndex::additionalData(), and
+ QXmlNodeModelIndex::model(). This means the hash key can be used for
+ node indexes from different node models.
+ */
+uint qHash(const QXmlNodeModelIndex &index)
+{
+ return uint(index.data() + index.additionalData() + quintptr(index.model()));
+}
+
+/*!
+ \enum QXmlNodeModelIndex::NodeKind
+
+ Identifies a kind of node.
+
+ \value Attribute Identifies an attribute node
+ \value Text Identifies a text node
+ \value Comment Identifies a comment node
+ \value Document Identifies a document node
+ \value Element Identifies an element node
+ \value Namespace Identifies a namespace node
+ \value ProcessingInstruction Identifies a processing instruction.
+
+ Note that the optional XML declaration at very beginning of the XML
+ document is not a processing instruction
+
+ \sa QAbstractXmlNodeModel::kind()
+*/
+
+/*!
+ \typedef QXmlNodeModelIndex::List
+
+ Typedef for QList<QXmlNodeModelIndex>.
+ */
+
+/*!
+ Returns true if this node is the same as \a other. This operator
+ does not compare values, children, or names of nodes. It compares
+ node identities, i.e., whether two nodes are from the same document
+ and are found at the exact same place.
+ */
+bool QXmlNodeModelIndex::operator==(const QXmlNodeModelIndex &other) const
+{
+ return !(m_storage != other.m_storage);
+}
+
+/*!
+ Returns true if \a other is the same node as this.
+ */
+bool QXmlNodeModelIndex::operator!=(const QXmlNodeModelIndex &other) const
+{
+ return !(operator==(other));
+}
+
+/*!
+ \fn QXmlNodeModelIndex::QXmlNodeModelIndex()
+
+ Default constructor. Creates an item that is \c null.
+
+ \sa isNull()
+ */
+
+/*!
+ \fn QXmlNodeModelIndex::QXmlNodeModelIndex(const QXmlNodeModelIndex &other)
+
+ Standard copy constructor. Creates a QXmlNodeModelIndex instance that
+ is a copy of \a other.
+ */
+
+/*!
+ \fn bool QXmlNodeModelIndex::isNull() const
+
+ Returns true if this QXmlNodeModelIndex is a default constructed
+ value, otherwise false.
+
+ A null QXmlNodeModelIndex doesn't represent any node and cannot
+ be used in conjunction with QAbstractXmlNodeModel.
+ */
+
+/*!
+ \fn const QAbstractXmlNodeModel *QXmlNodeModelIndex::model() const
+
+ Returns the QAbstractXmlNodeModel that this node index refers to.
+ QXmlNodeModelIndex does not own QAbstractXmlNodeModel and does not
+ keep track of its lifetime, so this pointer will dangle if the
+ QAbstractXmlNodeModel is deallocated first.
+
+ There is no setter for the node model because instances of
+ QXmlNodeModelIndex instances are only created with
+ QAbstractXmlNodeModel::createIndex().
+*/
+
+/*!
+ \fn qint64 QXmlNodeModelIndex::data() const
+
+ Returns the first data value. The node index holds two data values.
+ additionalData() returns the second one.
+
+ \sa additionalData()
+*/
+
+/*!
+ \fn void *QXmlNodeModelIndex::internalPointer() const
+
+ Returns the first data value as a void* pointer.
+
+ \sa additionalData()
+*/
+
+/*!
+ \fn qint64 QXmlNodeModelIndex::additionalData() const
+
+ Returns the second data value. The node index holds two data values.
+ data() returns the first one.
+
+ \sa data()
+*/
+
+/*!
+ \fn void QXmlNodeModelIndex::reset()
+ \internal
+
+ Resets this QXmlNodeModelIndex to be null. It is equivalent to
+ writing:
+
+ \snippet doc/src/snippets/code/src_xmlpatterns_api_qabstractxmlnodemodel.cpp 0
+ */
+
+/*!
+ \fn QXmlName QXmlNodeModelIndex::name() const
+ \internal
+*/
+
+/*!
+ \typedef QXmlNodeModelIndex::Iterator
+ \internal
+
+ Typedef for QAbstractXmlForwardIterator<QXmlNodeModelIndex>.
+ */
+/*!
+ \fn QXmlNodeModelIndex QXmlNodeModelIndex::root() const
+ \internal
+*/
+
+/*!
+ \fn QExplicitlySharedDataPointer<QAbstractXmlForwardIterator<QXmlNodeModelIndex> > QXmlNodeModelIndex::iterate(const Axis axis) const
+ \internal
+*/
+
+/*!
+ \fn QExplicitlySharedDataPointer<QAbstractXmlForwardIterator<QPatternist::Item> > QXmlNodeModelIndex::sequencedTypedValue() const
+ \internal
+*/
+
+/*!
+ \fn QUrl QXmlNodeModelIndex::documentUri() const
+ \internal
+*/
+
+/*!
+ \fn QUrl QXmlNodeModelIndex::baseUri() const
+ \internal
+*/
+
+/*!
+ \fn NodeKind QXmlNodeModelIndex::kind() const
+ \internal
+*/
+
+/*!
+ \fn bool QXmlNodeModelIndex::isDeepEqual(const QXmlNodeModelIndex &other) const
+ \internal
+*/
+
+/*!
+ \fn DocumentOrder QXmlNodeModelIndex::compareOrder(const QXmlNodeModelIndex &other) const
+ \internal
+*/
+
+/*!
+ \fn void QXmlNodeModelIndex::sendNamespaces(QAbstractXmlReceiver *const receiver) const
+ \internal
+*/
+
+/*!
+ \fn QVector<QXmlName> QXmlNodeModelIndex::namespaceBindings() const
+ \internal
+*/
+
+/*!
+ \fn QXmlNodeModelIndex QAbstractXmlNodeModel::elementById(const QXmlName &id) const
+
+ Returns the index of the element identified as \a id. XQuery's \c
+ id() function calls this function.
+
+ The node index returned will be the element node whose value is of
+ type \c ID and equals \a id, or it will be the element node that has
+ an attribute whose typed value is of type \c ID and equals \a id. If
+ there is no such element, a default constructed QXmlNodeModelIndex
+ instance is returned. The implementor guarantees that if the returned
+ node index is not null, it identifies an element.
+
+ It is not sufficient for an attribute or element to merely be called
+ \c id. Its value type must also be \c ID. However, the reserved name
+ \c xml:id is sufficient.
+
+ In \a id, the \c{namespace URI} and the \c{prefix} are undefined, and
+ the \c{local name} is the ID that should be looked up.
+
+ \sa {http://www.w3.org/TR/xpath-functions/#func-id}{XQuery 1.0 and XPath 2.0 Functions and Operators, 15.5.2 fn:id}
+ */
+
+/*!
+ \fn QVector<QXmlNodeModelIndex> QAbstractXmlNodeModel::nodesByIdref(const QXmlName &idref) const
+
+ Returns the elements and/or attributes that have an \c IDREF value
+ equal to \a idref. XQuery's \c idref() function calls this function.
+
+ The implementor guarantees that the nodes identified by the returned
+ indexes are elements or attributes.
+
+ It is not sufficient for an attribute or element to merely be called
+ \c idref. It must also be of type \c IDREF. Elements must be typed as
+ \c xs:IDREF or \c xs:IDREFS, or, in the case of attributes, as \c
+ IDREF or \c IDREFS in the schema.
+
+ In \a idref, the \c{namespace URI} and the \c{prefix} are undefined,
+ and the \c{local name} is the ID that should be looked up.
+
+ \sa {http://www.w3.org/TR/xpath-functions/#func-idref}{XQuery 1.0 and XPath 2.0 Functions and Operators, 15.5.3 fn:idref}
+ */
+
+/*!
+ \fn QXmlName::NamespaceCode QXmlNodeModelIndex::namespaceForPrefix(const QXmlName::PrefixCode prefix) const
+ \internal
+*/
+
+/*!
+ \fn QString QXmlNodeModelIndex::stringValue() const
+ \internal
+*/
+
+/*!
+ \fn QPatternist::ItemTypePtr QXmlNodeModelIndex::type() const
+ \internal
+*/
+
+/*!
+ \fn bool QXmlNodeModelIndex::is(const QXmlNodeModelIndex &other) const
+ \internal
+*/
+
+/*!
+ \enum QAbstractXmlNodeModel::NodeCopySetting
+ \internal
+
+ Controls how nodes are copied with copyNodeTo.
+
+ \value InheritNamespaces Copies the node with the \c copy-namespaces
+ setting being \c inherit. If not set, \c no-inherit is assumed.
+ \value PreserveNamespaces Copies the node with the \c copy-namespaces
+ settings being \c preserve. If not set, \c no-preserve is assumed.
+ */
+
+/*!
+ \typedef QAbstractXmlNodeModel::NodeCopySettings
+ \internal
+ */
+
+/*!
+ \internal
+
+ Copies node \a node to \a receiver, steered by \a copySettings.
+
+ The caller guarantees that \a node is not \c null, and that is
+ belongs to this QAbstractXmlNodeModel instance.
+
+ The caller guarantees that \a receiver is not \c null.
+*/
+void QAbstractXmlNodeModel::copyNodeTo(const QXmlNodeModelIndex &node,
+ QAbstractXmlReceiver *const receiver,
+ const NodeCopySettings &copySettings) const
+{
+ Q_UNUSED(node);
+ Q_UNUSED(receiver);
+ Q_UNUSED(copySettings);
+ Q_ASSERT_X(false, Q_FUNC_INFO,
+ "This function is not expected to be called.");
+}
+
+QT_END_NAMESPACE