xercesc/dom/DOMNodeIterator.hpp

0001 /*
0002  * Licensed to the Apache Software Foundation (ASF) under one or more
0003  * contributor license agreements.  See the NOTICE file distributed with
0004  * this work for additional information regarding copyright ownership.
0005  * The ASF licenses this file to You under the Apache License, Version 2.0
0006  * (the "License"); you may not use this file except in compliance with
0007  * the License.  You may obtain a copy of the License at
0008  *
0009  *      http://www.apache.org/licenses/LICENSE-2.0
0010  *
0011  * Unless required by applicable law or agreed to in writing, software
0012  * distributed under the License is distributed on an "AS IS" BASIS,
0013  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
0014  * See the License for the specific language governing permissions and
0015  * limitations under the License.
0016  */
0017
0018 /*
0019  * $Id$
0020  */
0021
0022 #if !defined(XERCESC_INCLUDE_GUARD_DOMNODEITERATOR_HPP)
0023 #define XERCESC_INCLUDE_GUARD_DOMNODEITERATOR_HPP
0024
0025 #include <xercesc/dom/DOMNodeFilter.hpp>
0026 #include <xercesc/dom/DOMNode.hpp>
0027
0028 XERCES_CPP_NAMESPACE_BEGIN
0029
0030
0031 /**
0032  * <code>DOMNodeIterators</code> are used to step through a set of nodes, e.g.
0033  * the set of nodes in a <code>DOMNodeList</code>, the document subtree
0034  * governed by a particular <code>DOMNode</code>, the results of a query, or
0035  * any other set of nodes. The set of nodes to be iterated is determined by
0036  * the implementation of the <code>DOMNodeIterator</code>. DOM Level 2
0037  * specifies a single <code>DOMNodeIterator</code> implementation for
0038  * document-order traversal of a document subtree. Instances of these
0039  * <code>DOMNodeIterators</code> are created by calling
0040  * <code>DOMDocumentTraversal</code><code>.createNodeIterator()</code>.
0041  * <p>See also the <a href='http://www.w3.org/TR/2000/REC-DOM-Level-2-Traversal-Range-20001113'>Document Object Model (DOM) Level 2 Traversal and Range Specification</a>.
0042  * @since DOM Level 2
0043  */
0044 class CDOM_EXPORT DOMNodeIterator
0045 {
0046 protected:
0047     // -----------------------------------------------------------------------
0048     //  Hidden constructors
0049     // -----------------------------------------------------------------------
0050     /** @name Hidden constructors */
0051     //@{
0052     DOMNodeIterator() {}
0053     DOMNodeIterator(const DOMNodeIterator &) {}
0054     //@}
0055
0056 private:
0057     // -----------------------------------------------------------------------
0058     // Unimplemented constructors and operators
0059     // -----------------------------------------------------------------------
0060     /** @name Unimplemented operators */
0061     //@{
0062     DOMNodeIterator & operator = (const DOMNodeIterator &);
0063     //@}
0064
0065 public:
0066     // -----------------------------------------------------------------------
0067     //  All constructors are hidden, just the destructor is available
0068     // -----------------------------------------------------------------------
0069     /** @name Destructor */
0070     //@{
0071     /**
0072      * Destructor
0073      *
0074      */
0075     virtual ~DOMNodeIterator() {};
0076     //@}
0077
0078     // -----------------------------------------------------------------------
0079     //  Virtual DOMNodeFilter interface
0080     // -----------------------------------------------------------------------
0081     /** @name Functions introduced in DOM Level 2 */
0082     //@{
0083     // -----------------------------------------------------------------------
0084     //  Getter methods
0085     // -----------------------------------------------------------------------
0086     /**
0087      * The <code>root</code> node of the <code>DOMNodeIterator</code>, as specified
0088      * when it was created.
0089      * @since DOM Level 2
0090      */
0091     virtual DOMNode*           getRoot() = 0;
0092     /**
0093      * Return which node types are presented via the iterator.
0094      * This attribute determines which node types are presented via the
0095      * <code>DOMNodeIterator</code>. The available set of constants is defined
0096      * in the <code>DOMNodeFilter</code> interface.  Nodes not accepted by
0097      * <code>whatToShow</code> will be skipped, but their children may still
0098      * be considered. Note that this skip takes precedence over the filter,
0099      * if any.
0100      * @since DOM Level 2
0101      *
0102      */
0103     virtual DOMNodeFilter::ShowType getWhatToShow() = 0;
0104
0105     /**
0106      * The <code>DOMNodeFilter</code> used to screen nodes.
0107      *
0108      * @since DOM Level 2
0109      */
0110     virtual DOMNodeFilter*     getFilter() = 0;
0111
0112     /**
0113      * Return the expandEntityReferences flag.
0114      * The value of this flag determines whether the children of entity
0115      * reference nodes are visible to the <code>DOMNodeIterator</code>. If
0116      * false, these children  and their descendants will be rejected. Note
0117      * that this rejection takes precedence over <code>whatToShow</code> and
0118      * the filter. Also note that this is currently the only situation where
0119      * <code>DOMNodeIterators</code> may reject a complete subtree rather than
0120      * skipping individual nodes.
0121      * <br>
0122      * <br> To produce a view of the document that has entity references
0123      * expanded and does not expose the entity reference node itself, use
0124      * the <code>whatToShow</code> flags to hide the entity reference node
0125      * and set <code>expandEntityReferences</code> to true when creating the
0126      * <code>DOMNodeIterator</code>. To produce a view of the document that has
0127      * entity reference nodes but no entity expansion, use the
0128      * <code>whatToShow</code> flags to show the entity reference node and
0129      * set <code>expandEntityReferences</code> to false.
0130      *
0131      * @since DOM Level 2
0132      */
0133     virtual bool               getExpandEntityReferences() = 0;
0134
0135     // -----------------------------------------------------------------------
0136     //  Query methods
0137     // -----------------------------------------------------------------------
0138     /**
0139      * Returns the next node in the set and advances the position of the
0140      * <code>DOMNodeIterator</code> in the set. After a
0141      * <code>DOMNodeIterator</code> is created, the first call to
0142      * <code>nextNode()</code> returns the first node in the set.
0143      * @return The next <code>DOMNode</code> in the set being iterated over, or
0144      *   <code>null</code> if there are no more members in that set.
0145      * @exception DOMException
0146      *   INVALID_STATE_ERR: Raised if this method is called after the
0147      *   <code>detach</code> method was invoked.
0148      * @since DOM Level 2
0149      */
0150     virtual DOMNode*           nextNode() = 0;
0151
0152     /**
0153      * Returns the previous node in the set and moves the position of the
0154      * <code>DOMNodeIterator</code> backwards in the set.
0155      * @return The previous <code>DOMNode</code> in the set being iterated over,
0156      *   or <code>null</code> if there are no more members in that set.
0157      * @exception DOMException
0158      *   INVALID_STATE_ERR: Raised if this method is called after the
0159      *   <code>detach</code> method was invoked.
0160      * @since DOM Level 2
0161      */
0162     virtual DOMNode*           previousNode() = 0;
0163
0164     /**
0165      * Detaches the <code>DOMNodeIterator</code> from the set which it iterated
0166      * over, releasing any computational resources and placing the
0167      * <code>DOMNodeIterator</code> in the INVALID state. After
0168      * <code>detach</code> has been invoked, calls to <code>nextNode</code>
0169      * or <code>previousNode</code> will raise the exception
0170      * INVALID_STATE_ERR.
0171      * @since DOM Level 2
0172      */
0173     virtual void               detach() = 0;
0174     //@}
0175
0176     // -----------------------------------------------------------------------
0177     //  Non-standard Extension
0178     // -----------------------------------------------------------------------
0179     /** @name Non-standard Extension */
0180     //@{
0181     /**
0182      * Called to indicate that this NodeIterator is no longer in use
0183      * and that the implementation may relinquish any resources associated with it.
0184      * (release() will call detach() where appropriate)
0185      *
0186      * Access to a released object will lead to unexpected result.
0187      */
0188     virtual void               release() = 0;
0189     //@}
0190 };
0191
0192 #define GetDOMNodeIteratorMemoryManager GET_DIRECT_MM(fDocument)
0193
0194 XERCES_CPP_NAMESPACE_END
0195
0196 #endif