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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
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*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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package javax.sound.sampled;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
/**
* An instance of the {@code AudioFileFormat} class describes an audio file,
* including the file type, the file's length in bytes, the length in sample
* frames of the audio data contained in the file, and the format of the audio
* data.
* <p>
* The {@link AudioSystem} class includes methods for determining the format of
* an audio file, obtaining an audio input stream from an audio file, and
* writing an audio file from an audio input stream.
* <p>
* An {@code AudioFileFormat} object can include a set of properties. A property
* is a pair of key and value: the key is of type {@code String}, the associated
* property value is an arbitrary object. Properties specify additional
* informational meta data (like a author, copyright, or file duration).
* Properties are optional information, and file reader and file writer
* implementations are not required to provide or recognize properties.
* <p>
* The following table lists some common properties that should be used in
* implementations:
*
* <table border=1>
* <caption>Audio File Format Properties</caption>
* <tr>
* <th>Property key</th>
* <th>Value type</th>
* <th>Description</th>
* </tr>
* <tr>
* <td>"duration"</td>
* <td>{@link java.lang.Long Long}</td>
* <td>playback duration of the file in microseconds</td>
* </tr>
* <tr>
* <td>"author"</td>
* <td>{@link java.lang.String String}</td>
* <td>name of the author of this file</td>
* </tr>
* <tr>
* <td>"title"</td>
* <td>{@link java.lang.String String}</td>
* <td>title of this file</td>
* </tr>
* <tr>
* <td>"copyright"</td>
* <td>{@link java.lang.String String}</td>
* <td>copyright message</td>
* </tr>
* <tr>
* <td>"date"</td>
* <td>{@link java.util.Date Date}</td>
* <td>date of the recording or release</td>
* </tr>
* <tr>
* <td>"comment"</td>
* <td>{@link java.lang.String String}</td>
* <td>an arbitrary text</td>
* </tr>
* </table>
*
*
* @author David Rivas
* @author Kara Kytle
* @author Florian Bomers
* @see AudioInputStream
* @since 1.3
*/
public class AudioFileFormat {
/**
* File type.
*/
private Type type;
/**
* File length in bytes.
*/
private int byteLength;
/**
* Format of the audio data contained in the file.
*/
private AudioFormat format;
/**
* Audio data length in sample frames.
*/
private int frameLength;
/**
* The set of properties.
*/
private HashMap<String, Object> properties;
/**
* Constructs an audio file format object. This protected constructor is
* intended for use by providers of file-reading services when returning
* information about an audio file or about supported audio file formats.
*
* @param type the type of the audio file
* @param byteLength the length of the file in bytes, or
* {@code AudioSystem.NOT_SPECIFIED}
* @param format the format of the audio data contained in the file
* @param frameLength the audio data length in sample frames, or
* {@code AudioSystem.NOT_SPECIFIED}
* @see #getType
*/
protected AudioFileFormat(Type type, int byteLength, AudioFormat format, int frameLength) {
this.type = type;
this.byteLength = byteLength;
this.format = format;
this.frameLength = frameLength;
this.properties = null;
}
/**
* Constructs an audio file format object. This public constructor may be
* used by applications to describe the properties of a requested audio
* file.
*
* @param type the type of the audio file
* @param format the format of the audio data contained in the file
* @param frameLength the audio data length in sample frames, or
* {@code AudioSystem.NOT_SPECIFIED}
*/
public AudioFileFormat(Type type, AudioFormat format, int frameLength) {
this(type,AudioSystem.NOT_SPECIFIED,format,frameLength);
}
/**
* Construct an audio file format object with a set of defined properties.
* This public constructor may be used by applications to describe the
* properties of a requested audio file. The properties map will be copied
* to prevent any changes to it.
*
* @param type the type of the audio file
* @param format the format of the audio data contained in the file
* @param frameLength the audio data length in sample frames, or
* {@code AudioSystem.NOT_SPECIFIED}
* @param properties a {@code Map<String, Object>} object with properties
* @since 1.5
*/
public AudioFileFormat(Type type, AudioFormat format,
int frameLength, Map<String, Object> properties) {
this(type,AudioSystem.NOT_SPECIFIED,format,frameLength);
this.properties = new HashMap<String, Object>(properties);
}
/**
* Obtains the audio file type, such as {@code WAVE} or {@code AU}.
*
* @return the audio file type
* @see Type#WAVE
* @see Type#AU
* @see Type#AIFF
* @see Type#AIFC
* @see Type#SND
*/
public Type getType() {
return type;
}
/**
* Obtains the size in bytes of the entire audio file (not just its audio
* data).
*
* @return the audio file length in bytes
* @see AudioSystem#NOT_SPECIFIED
*/
public int getByteLength() {
return byteLength;
}
/**
* Obtains the format of the audio data contained in the audio file.
*
* @return the audio data format
*/
public AudioFormat getFormat() {
return format;
}
/**
* Obtains the length of the audio data contained in the file, expressed in
* sample frames.
*
* @return the number of sample frames of audio data in the file
* @see AudioSystem#NOT_SPECIFIED
*/
public int getFrameLength() {
return frameLength;
}
/**
* Obtain an unmodifiable map of properties. The concept of properties is
* further explained in the {@link AudioFileFormat class description}.
*
* @return a {@code Map<String, Object>} object containing all properties.
* If no properties are recognized, an empty map is returned.
* @see #getProperty(String)
* @since 1.5
*/
@SuppressWarnings("unchecked") // Cast of result of clone
public Map<String, Object> properties() {
Map<String,Object> ret;
if (properties == null) {
ret = new HashMap<>(0);
} else {
ret = (Map<String,Object>) (properties.clone());
}
return Collections.unmodifiableMap(ret);
}
/**
* Obtain the property value specified by the key. The concept of properties
* is further explained in the {@link AudioFileFormat class description}.
* <p>
* If the specified property is not defined for a particular file format,
* this method returns {@code null}.
*
* @param key the key of the desired property
* @return the value of the property with the specified key, or {@code null}
* if the property does not exist
* @see #properties()
* @since 1.5
*/
public Object getProperty(String key) {
if (properties == null) {
return null;
}
return properties.get(key);
}
/**
* Provides a string representation of the file format.
*
* @return the file format as a string
*/
@Override
public String toString() {
StringBuffer buf = new StringBuffer();
//$$fb2002-11-01: fix for 4672864: AudioFileFormat.toString() throws unexpected NullPointerException
if (type != null) {
buf.append(type.toString() + " (." + type.getExtension() + ") file");
} else {
buf.append("unknown file format");
}
if (byteLength != AudioSystem.NOT_SPECIFIED) {
buf.append(", byte length: " + byteLength);
}
buf.append(", data format: " + format);
if (frameLength != AudioSystem.NOT_SPECIFIED) {
buf.append(", frame length: " + frameLength);
}
return new String(buf);
}
/**
* An instance of the {@code Type} class represents one of the standard
* types of audio file. Static instances are provided for the common types.
*/
public static class Type {
// FILE FORMAT TYPE DEFINES
/**
* Specifies a WAVE file.
*/
public static final Type WAVE = new Type("WAVE", "wav");
/**
* Specifies an AU file.
*/
public static final Type AU = new Type("AU", "au");
/**
* Specifies an AIFF file.
*/
public static final Type AIFF = new Type("AIFF", "aif");
/**
* Specifies an AIFF-C file.
*/
public static final Type AIFC = new Type("AIFF-C", "aifc");
/**
* Specifies a SND file.
*/
public static final Type SND = new Type("SND", "snd");
/**
* File type name.
*/
private final String name;
/**
* File type extension.
*/
private final String extension;
/**
* Constructs a file type.
*
* @param name the string that names the file type
* @param extension the string that commonly marks the file type
* without leading dot
*/
public Type(String name, String extension) {
this.name = name;
this.extension = extension;
}
/**
* Finalizes the equals method.
*/
@Override
public final boolean equals(Object obj) {
if (toString() == null) {
return (obj != null) && (obj.toString() == null);
}
if (obj instanceof Type) {
return toString().equals(obj.toString());
}
return false;
}
/**
* Finalizes the hashCode method.
*/
@Override
public final int hashCode() {
if (toString() == null) {
return 0;
}
return toString().hashCode();
}
/**
* Provides the file type's name as the {@code String} representation of
* the file type.
*
* @return the file type's name
*/
@Override
public final String toString() {
return name;
}
/**
* Obtains the common file name extension for this file type.
*
* @return file type extension
*/
public String getExtension() {
return extension;
}
}
}