1 /***************************************************************************
2 copyright : (C) 2002 - 2008 by Scott Wheeler
3 email : wheeler@kde.org
4 ***************************************************************************/
6 /***************************************************************************
7 * This library is free software; you can redistribute it and/or modify *
8 * it under the terms of the GNU Lesser General Public License version *
9 * 2.1 as published by the Free Software Foundation. *
11 * This library is distributed in the hope that it will be useful, but *
12 * WITHOUT ANY WARRANTY; without even the implied warranty of *
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14 * Lesser General Public License for more details. *
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21 * Alternatively, this file is available under the Mozilla Public *
22 * License Version 1.1. You may obtain a copy of the License at *
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24 ***************************************************************************/
26 #ifndef TAGLIB_ID3V2FRAMEFACTORY_H
27 #define TAGLIB_ID3V2FRAMEFACTORY_H
29 #include "taglib_export.h"
30 #include "tbytevector.h"
31 #include "id3v2frame.h"
32 #include "id3v2header.h"
38 class TextIdentificationFrame;
40 //! A factory for creating ID3v2 frames during parsing
43 * This factory abstracts away the frame creation process and instantiates
44 * the appropriate ID3v2::Frame subclasses based on the contents of the
47 * Reimplementing this factory is the key to adding support for frame types
48 * not directly supported by TagLib to your application. To do so you would
49 * subclass this factory reimplement createFrame(). Then by setting your
50 * factory to be the default factory in ID3v2::Tag constructor or with
51 * MPEG::File::setID3v2FrameFactory() you can implement behavior that will
52 * allow for new ID3v2::Frame subclasses (also provided by you) to be used.
54 * This implements both <i>abstract factory</i> and <i>singleton</i> patterns
55 * of which more information is available on the web and in software design
56 * textbooks (Notably <i>Design Patters</i>).
58 * \note You do not need to use this factory to create new frames to add to
59 * an ID3v2::Tag. You can instantiate frame subclasses directly (with new)
60 * and add them to a tag using ID3v2::Tag::addFrame()
62 * \see ID3v2::Tag::addFrame()
65 class TAGLIB_EXPORT FrameFactory
68 static FrameFactory *instance();
70 * Create a frame based on \a data. \a synchSafeInts should only be set
71 * false if we are parsing an old tag (v2.3 or older) that does not support
74 * \deprecated Please use the method below that accepts a ID3v2::Header
75 * instance in new code.
77 Frame *createFrame(const ByteVector &data, bool synchSafeInts) const;
80 * Create a frame based on \a data. \a version should indicate the ID3v2
81 * version of the tag. As ID3v2.4 is the most current version of the
82 * standard 4 is the default.
84 * \deprecated Please use the method below that accepts a ID3v2::Header
85 * instance in new code.
87 Frame *createFrame(const ByteVector &data, uint version = 4) const;
90 * Create a frame based on \a data. \a tagHeader should be a valid
91 * ID3v2::Header instance.
94 Frame *createFrame(const ByteVector &data, Header *tagHeader) const;
97 * Returns the default text encoding for text frames. If setTextEncoding()
98 * has not been explicitly called this will only be used for new text
99 * frames. However, if this value has been set explicitly all frames will be
100 * converted to this type (unless it's explitly set differently for the
101 * individual frame) when being rendered.
103 * \see setDefaultTextEncoding()
105 String::Type defaultTextEncoding() const;
108 * Set the default text encoding for all text frames that are created to
109 * \a encoding. If no value is set the frames with either default to the
110 * encoding type that was parsed and new frames default to Latin1.
112 * Valid string types for ID3v2 tags are Latin1, UTF8, UTF16 and UTF16BE.
114 * \see defaultTextEncoding()
116 void setDefaultTextEncoding(String::Type encoding);
120 * Constructs a frame factory. Because this is a singleton this method is
121 * protected, but may be used for subclasses.
126 * Destroys the frame factory. In most cases this will never be called (as
127 * is typical of singletons).
129 virtual ~FrameFactory();
132 * This method checks for compliance to the current ID3v2 standard (2.4)
133 * and does nothing in the common case. However if a frame is found that
134 * is not compatible with the current standard, this method either updates
135 * the frame or indicates that it should be discarded.
137 * This method with return true (with or without changes to the frame) if
138 * this frame should be kept or false if it should be discarded.
140 * See the id3v2.4.0-changes.txt document for further information.
142 virtual bool updateFrame(Frame::Header *header) const;
145 FrameFactory(const FrameFactory &);
146 FrameFactory &operator=(const FrameFactory &);
149 * This method is used internally to convert a frame from ID \a from to ID
150 * \a to. If the frame matches the \a from pattern and converts the frame
151 * ID in the \a header or simply does nothing if the frame ID does not match.
153 void convertFrame(const char *from, const char *to,
154 Frame::Header *header) const;
156 void updateGenre(TextIdentificationFrame *frame) const;
158 static FrameFactory *factory;
160 class FrameFactoryPrivate;
161 FrameFactoryPrivate *d;