#ifndef DOMNodeFilter_HEADER_GUARD_

#define DOMNodeFilter_HEADER_GUARD_

/*

 * Licensed to the Apache Software Foundation (ASF) under one or more

 * contributor license agreements.  See the NOTICE file distributed with

 * this work for additional information regarding copyright ownership.

 * The ASF licenses this file to You under the Apache License, Version 2.0

 * (the "License"); you may not use this file except in compliance with

 * the License.  You may obtain a copy of the License at

 * 

 *      http://www.apache.org/licenses/LICENSE-2.0

 * 

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

/*

 * $Id: DOMNodeFilter.hpp 568078 2007-08-21 11:43:25Z amassari $

 */

#include <xercesc/dom/DOMNode.hpp>

XERCES_CPP_NAMESPACE_BEGIN

/**

 * Filters are objects that know how to "filter out" nodes. If a

 * <code>DOMNodeIterator</code> or <code>DOMTreeWalker</code> is given a

 * <code>DOMNodeFilter</code>, it applies the filter before it returns the next

 * node. If the filter says to accept the node, the traversal logic returns

 * it; otherwise, traversal looks for the next node and pretends that the

 * node that was rejected was not there.

 * <p>The DOM does not provide any filters. <code>DOMNodeFilter</code> is just an

 * interface that users can implement to provide their own filters.

 * <p><code>DOMNodeFilters</code> do not need to know how to traverse from node

 * to node, nor do they need to know anything about the data structure that

 * is being traversed. This makes it very easy to write filters, since the

 * only thing they have to know how to do is evaluate a single node. One

 * filter may be used with a number of different kinds of traversals,

 * encouraging code reuse.

 * <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>.

 * @since DOM Level 2

 */

class CDOM_EXPORT DOMNodeFilter

{

protected:

    // -----------------------------------------------------------------------

    //  Hidden constructors

    // -----------------------------------------------------------------------

    /** @name Hidden constructors */

    //@{    

    DOMNodeFilter() {};

    //@}    

private:

    // -----------------------------------------------------------------------

    // Unimplemented constructors and operators

    // -----------------------------------------------------------------------

    /** @name Unimplemented constructors and operators */

    //@{

    DOMNodeFilter(const DOMNodeFilter &);

    DOMNodeFilter & operator = (const DOMNodeFilter &);

    //@}

public:

    // -----------------------------------------------------------------------

    //  All constructors are hidden, just the destructor is available

    // -----------------------------------------------------------------------

    /** @name Destructor */

    //@{

    /**

     * Destructor

     *

     */

    virtual ~DOMNodeFilter() {};

    //@}

    // -----------------------------------------------------------------------

    //  Class Types

    // -----------------------------------------------------------------------

    /** @name Public Contants */

    //@{

    /**

     * Constants returned by acceptNode.

     *

     * <p><code>FILTER_ACCEPT:</code>

     * Accept the node. Navigation methods defined for

     * <code>DOMNodeIterator</code> or <code>DOMTreeWalker</code> will return this

     * node.</p>

     *

     * <p><code>FILTER_REJECT:</code>

     * Reject the node. Navigation methods defined for

     * <code>DOMNodeIterator</code> or <code>DOMTreeWalker</code> will not return

     * this node. For <code>DOMTreeWalker</code>, the children of this node

     * will also be rejected. <code>DOMNodeIterators</code> treat this as a

     * synonym for <code>FILTER_SKIP.</code></p>

     *

     * <p><code>FILTER_SKIP:</code>

     * Skip this single node. Navigation methods defined for

     * <code>DOMNodeIterator</code> or <code>DOMTreeWalker</code> will not return

     * this node. For both <code>DOMNodeIterator</code> and

     * <code>DOMTreeWalker</code>, the children of this node will still be

     * considered.</p>

     *

     * @since DOM Level 2

     */

    enum FilterAction {FILTER_ACCEPT = 1,

                       FILTER_REJECT = 2,

                       FILTER_SKIP   = 3};

    /**

     * Constants for whatToShow

     *

     * <p><code>SHOW_ALL:</code>

     * Show all <code>DOMNode(s)</code>.</p>

     *

     * <p><code>SHOW_ELEMENT:</code>

     * Show <code>DOMElement</code> nodes.</p>

     *

     * <p><code>SHOW_ATTRIBUTE:</code>

     * Show <code>DOMAttr</code> nodes. This is meaningful only when creating an

     * <code>DOMNodeIterator</code> or <code>DOMTreeWalker</code> with an

     * attribute node as its <code>root</code>; in this case, it means that

     * the attribute node will appear in the first position of the iteration

     * or traversal. Since attributes are never children of other nodes,

     * they do not appear when traversing over the document tree.</p>

     *

     * <p><code>SHOW_TEXT:</code>

     * Show <code>DOMText</code> nodes.</p>

     *

     * <p><code>SHOW_CDATA_SECTION:</code>

     * Show <code>DOMCDATASection</code> nodes.</p>

     *

     * <p><code>SHOW_ENTITY_REFERENCE:</code>

     * Show <code>DOMEntityReference</code> nodes.</p>

     *

     * <p><code>SHOW_ENTITY:</code>

     * Show <code>DOMEntity</code> nodes. This is meaningful only when creating

     * an <code>DOMNodeIterator</code> or <code>DOMTreeWalker</code> with an

     * <code>DOMEntity</code> node as its <code>root</code>; in this case, it

     * means that the <code>DOMEntity</code> node will appear in the first

     * position of the traversal. Since entities are not part of the

     * document tree, they do not appear when traversing over the document

     * tree.</p>

     *

     * <p><code>SHOW_PROCESSING_INSTRUCTION:</code>

     * Show <code>DOMProcessingInstruction</code> nodes.</p>

     *

     * <p><code>SHOW_COMMENT:</code>

     * Show <code>DOMComment</code> nodes.</p>

     *

     * <p><code>SHOW_DOCUMENT:</code>

     * Show <code>DOMDocument</code> nodes.</p>

     *

     * <p><code>SHOW_DOCUMENT_TYPE:</code>

     * Show <code>DOMDocumentType</code> nodes.</p>

     *

     * <p><code>SHOW_DOCUMENT_FRAGMENT:</code>

     * Show <code>DOMDocumentFragment</code> nodes.</p>

     *

     * <p><code>SHOW_NOTATION:</code>

     * Show <code>DOMNotation</code> nodes. This is meaningful only when creating

     * an <code>DOMNodeIterator</code> or <code>DOMTreeWalker</code> with a

     * <code>DOMNotation</code> node as its <code>root</code>; in this case, it

     * means that the <code>DOMNotation</code> node will appear in the first

     * position of the traversal. Since notations are not part of the

     * document tree, they do not appear when traversing over the document

     * tree.</p>

     *

     * @since DOM Level 2

     */

    enum ShowType {

        SHOW_ALL                       = 0x0000FFFF,

        SHOW_ELEMENT                   = 0x00000001,

        SHOW_ATTRIBUTE                 = 0x00000002,

        SHOW_TEXT                      = 0x00000004,

        SHOW_CDATA_SECTION             = 0x00000008,

        SHOW_ENTITY_REFERENCE          = 0x00000010,

        SHOW_ENTITY                    = 0x00000020,

        SHOW_PROCESSING_INSTRUCTION    = 0x00000040,

        SHOW_COMMENT                   = 0x00000080,

        SHOW_DOCUMENT                  = 0x00000100,

        SHOW_DOCUMENT_TYPE             = 0x00000200,

        SHOW_DOCUMENT_FRAGMENT         = 0x00000400,

        SHOW_NOTATION                  = 0x00000800

    };

    //@}

    // -----------------------------------------------------------------------

    //  Virtual DOMNodeFilter interface

    // -----------------------------------------------------------------------

    /** @name Functions introduced in DOM Level 2 */

    //@{

    /**

     * Test whether a specified node is visible in the logical view of a

     * <code>DOMTreeWalker</code> or <code>DOMNodeIterator</code>. This function

     * will be called by the implementation of <code>DOMTreeWalker</code> and

     * <code>DOMNodeIterator</code>; it is not normally called directly from

     * user code. (Though you could do so if you wanted to use the same

     * filter to guide your own application logic.)

     * @param node The node to check to see if it passes the filter or not.

     * @return A constant to determine whether the node is accepted,

     *   rejected, or skipped, as defined above.

     * @since DOM Level 2

     */

    virtual short acceptNode (const DOMNode* node) const =0;

    //@}

};

XERCES_CPP_NAMESPACE_END

#endif