1/*
2 * This file is part of the syndication library
3 *
4 * Copyright (C) 2006 Frank Osterfeld <osterfeld@kde.org>
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Library General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Library General Public License for more details.
15 *
16 * You should have received a copy of the GNU Library General Public License
17 * along with this library; see the file COPYING.LIB. If not, write to
18 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
19 * Boston, MA 02110-1301, USA.
20 *
21 */
22
23#ifndef SYNDICATION_CATEGORY_H
24#define SYNDICATION_CATEGORY_H
25
26#include <QtCore/QString>
27#include <boost/shared_ptr.hpp>
28
29#include "ksyndication_export.h"
30
31namespace Syndication {
32
33class Category;
34typedef boost::shared_ptr<Category> CategoryPtr;
35
36/**
37 * A category for categorizing items or whole feeds.
38 * A category can be an informal string set by the feed author ("General",
39 * "Stuff I like"), a tag assigned by readers, as known from flickr.com
40 * or de.licio.us ("KDE", "funny"), or a term from a formally defined ontology.
41 *
42 * To represent the category in a user interface, use label() (or term() as
43 * fallback). To create a key for e.g. storage purposes, use scheme() + term().
44 *
45 * @author Frank Osterfeld
46 */
47class SYNDICATION_EXPORT Category
48{
49 public:
50
51 /**
52 * destructor
53 */
54 virtual ~Category();
55
56 /**
57 * returns whether this object is a null category
58 */
59 virtual bool isNull() const = 0;
60
61
62 /**
63 * A term identifying the category, e.g. "general", "life", "books"
64 * or "Basketball & other sport I like".
65 * The term must be unique in its scheme (see scheme()).
66 *
67 * In user interfaces, use it only if there is no label() available.
68 * TODO: specify format (HTML, plain text?) and enforce it in the impl
69 * @return category term. This string is never empty.
70 */
71 virtual QString term() const = 0;
72
73 /**
74 * An optional scheme the term is part of. This can be some
75 * vocabulary/ontology such as Dublin Core.
76 * Think of it as the term's namespace, grouping a set of categories.
77 * When managing categories, scheme() + term() identifies a category
78 * unambigously and can be used as key.
79 *
80 * @return the scheme this category is part of, or a null string
81 * if not specified
82 */
83 virtual QString scheme() const = 0;
84
85 /**
86 * An optional human-readable label of the category. If specified, this
87 * string should be used to represent this category in a user interface.
88 * If not specified, use term() instead.
89 * TODO: specify format (HTML, plain text?) and enforce it in the impl
90 * @return the label of this category, or a null string if not specified
91 */
92 virtual QString label() const = 0;
93
94 /**
95 * Description of the category for debugging purposes.
96 *
97 * @return debug string
98 */
99 virtual QString debugInfo() const;
100};
101
102} // namespace Syndication
103
104#endif // SYNDICATION_CATEGORY_H
105