1/*
2 * Copyright (c) 1999, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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24 */
25
26package javax.sound.midi.spi;
27
28import java.io.File;
29import java.io.IOException;
30import java.io.InputStream;
31import java.net.URL;
32
33import javax.sound.midi.InvalidMidiDataException;
34import javax.sound.midi.MidiFileFormat;
35import javax.sound.midi.Sequence;
36
37/**
38 * A {@code MidiFileReader} supplies MIDI file-reading services. Classes
39 * implementing this interface can parse the format information from one or more
40 * types of MIDI file, and can produce a {@link Sequence} object from files of
41 * these types.
42 *
43 * @author Kara Kytle
44 * @since 1.3
45 */
46public abstract class MidiFileReader {
47
48    /**
49     * Obtains the MIDI file format of the input stream provided. The stream
50     * must point to valid MIDI file data. In general, MIDI file readers may
51     * need to read some data from the stream before determining whether they
52     * support it. These parsers must be able to mark the stream, read enough
53     * data to determine whether they support the stream, and, if not, reset the
54     * stream's read pointer to its original position. If the input stream does
55     * not support this, this method may fail with an {@code IOException}.
56     *
57     * @param  stream the input stream from which file format information should
58     *         be extracted
59     * @return a {@code MidiFileFormat} object describing the MIDI file format
60     * @throws InvalidMidiDataException if the stream does not point to valid
61     *         MIDI file data recognized by the system
62     * @throws IOException if an I/O exception occurs
63     * @throws NullPointerException if {@code stream} is {@code null}
64     * @see InputStream#markSupported
65     * @see InputStream#mark
66     */
67    public abstract MidiFileFormat getMidiFileFormat(InputStream stream)
68            throws InvalidMidiDataException, IOException;
69
70    /**
71     * Obtains the MIDI file format of the {@code URL} provided. The {@code URL}
72     * must point to valid MIDI file data.
73     *
74     * @param  url the {@code URL} from which file format information should be
75     *         extracted
76     * @return a {@code MidiFileFormat} object describing the MIDI file format
77     * @throws InvalidMidiDataException if the {@code URL} does not point to
78     *         valid MIDI file data recognized by the system
79     * @throws IOException if an I/O exception occurs
80     * @throws NullPointerException if {@code url} is {@code null}
81     */
82    public abstract MidiFileFormat getMidiFileFormat(URL url)
83            throws InvalidMidiDataException, IOException;
84
85    /**
86     * Obtains the MIDI file format of the {@code File} provided. The
87     * {@code File} must point to valid MIDI file data.
88     *
89     * @param  file the {@code File} from which file format information should
90     *         be extracted
91     * @return a {@code MidiFileFormat} object describing the MIDI file format
92     * @throws InvalidMidiDataException if the {@code File} does not point to
93     *         valid MIDI file data recognized by the system
94     * @throws IOException if an I/O exception occurs
95     * @throws NullPointerException if {@code file} is {@code null}
96     */
97    public abstract MidiFileFormat getMidiFileFormat(File file)
98            throws InvalidMidiDataException, IOException;
99
100    /**
101     * Obtains a MIDI sequence from the input stream provided. The stream must
102     * point to valid MIDI file data. In general, MIDI file readers may need to
103     * read some data from the stream before determining whether they support
104     * it. These parsers must be able to mark the stream, read enough data to
105     * determine whether they support the stream, and, if not, reset the
106     * stream's read pointer to its original position. If the input stream does
107     * not support this, this method may fail with an {@code IOException}.
108     *
109     * @param  stream the input stream from which the {@code Sequence} should be
110     *         constructed
111     * @return a {@code Sequence} object based on the MIDI file data contained
112     *         in the input stream
113     * @throws InvalidMidiDataException if the stream does not point to valid
114     *         MIDI file data recognized by the system
115     * @throws IOException if an I/O exception occurs
116     * @throws NullPointerException if {@code stream} is {@code null}
117     * @see InputStream#markSupported
118     * @see InputStream#mark
119     */
120    public abstract Sequence getSequence(InputStream stream)
121            throws InvalidMidiDataException, IOException;
122
123    /**
124     * Obtains a MIDI sequence from the {@code URL} provided. The {@code URL}
125     * must point to valid MIDI file data.
126     *
127     * @param  url the {@code URL} for which the {@code Sequence} should be
128     *         constructed
129     * @return a {@code Sequence} object based on the MIDI file data pointed to
130     *         by the {@code URL}
131     * @throws InvalidMidiDataException if the {@code URL} does not point to
132     *         valid MIDI file data recognized by the system
133     * @throws IOException if an I/O exception occurs
134     * @throws NullPointerException if {@code url} is {@code null}
135     */
136    public abstract Sequence getSequence(URL url)
137            throws InvalidMidiDataException, IOException;
138
139    /**
140     * Obtains a MIDI sequence from the {@code File} provided. The {@code File}
141     * must point to valid MIDI file data.
142     *
143     * @param  file the {@code File} from which the {@code Sequence} should be
144     *         constructed
145     * @return a {@code Sequence} object based on the MIDI file data pointed to
146     *         by the {@code File}
147     * @throws InvalidMidiDataException if the {@code File} does not point to
148     *         valid MIDI file data recognized by the system
149     * @throws IOException if an I/O exception occurs
150     * @throws NullPointerException if {@code file} is {@code null}
151     */
152    public abstract Sequence getSequence(File file)
153            throws InvalidMidiDataException, IOException;
154}
155