File indexing completed on 2024-07-21 12:16:49

0001 /*
0002     This file is part of the syndication library
0003     SPDX-FileCopyrightText: 2005 Frank Osterfeld <osterfeld@kde.org>
0004 
0005     SPDX-License-Identifier: LGPL-2.0-or-later
0006 */
0007 
0008 #ifndef SYNDICATION_SPECIFICDOCUMENT_H
0009 #define SYNDICATION_SPECIFICDOCUMENT_H
0010 
0011 #include "syndication_export.h"
0012 
0013 #include <QSharedPointer>
0014 
0015 class QString;
0016 
0017 namespace Syndication
0018 {
0019 class DocumentVisitor;
0020 class SpecificDocument;
0021 
0022 //@cond PRIVATE
0023 typedef QSharedPointer<SpecificDocument> SpecificDocumentPtr;
0024 //@endcond
0025 
0026 /**
0027  * Document interface for format-specific feed documents as parsed from a
0028  * document source (see DocumentSource).
0029  * The Document classes from the several syndication formats must implement
0030  * this interface. It's main purpose is to provide access for document visitors
0031  * (see DocumentVisitor).
0032  * Usually it is not necessary to access the format-specific document at all,
0033  * use Feed for a format-agnostic interface to all feed documents supported by
0034  * the library.
0035  *
0036  * @author Frank Osterfeld
0037  */
0038 class SYNDICATION_EXPORT SpecificDocument
0039 {
0040 public:
0041     /**
0042      * virtual dtor
0043      */
0044     virtual ~SpecificDocument();
0045 
0046     /**
0047      * This must be implemented for the double dispatch
0048      * technique (Visitor pattern).
0049      *
0050      * The usual implementation is
0051      * @code
0052      * return visitor->visit(this);
0053      * @endcode
0054      *
0055      * See also DocumentVisitor.
0056      *
0057      * @param visitor the visitor "visiting" this object
0058      */
0059     virtual bool accept(DocumentVisitor *visitor) = 0;
0060 
0061     /**
0062      * Returns whether this document is valid or not.
0063      * Invalid documents do not contain any useful
0064      * information.
0065      */
0066     virtual bool isValid() const = 0;
0067 
0068     /**
0069      * Returns a description of the document for debugging purposes.
0070      *
0071      * @return debug string
0072      */
0073     virtual QString debugInfo() const = 0;
0074 };
0075 
0076 } // namespace Syndication
0077 
0078 #endif // SYNDICATION_SPECIFICDOCUMENT_H