/*
* @(#)AudioFileFormat.java 1.23 03/12/19
*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package javax.sound.sampled;
import java.io.File;
import java.io.OutputStream;
import java.io.IOException;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
/**
* An instance of the <code>AudioFileFormat</code> 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 <code>{@link AudioSystem}</code> 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</code> object can
* include a set of properties. A property is a pair of key and value:
* the key is of type <code>String</code>, 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>
* <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
* @version 1.23 03/12/19
* @see AudioInputStream
* @since 1.3
*/
public class AudioFileFormat {
// INSTANCE VARIABLES
/**
* 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</code>
* @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</code>
*
* @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</code>
*/
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</code>
* @param properties a <code>Map<String,Object></code> 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</code> or <code>AU</code>.
* @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></code> object containing
* all properties. If no properties are recognized, an empty map is
* returned.
*
* @see #getProperty(String)
* @since 1.5
*/
public Map<String,Object> properties() {
Map<String,Object> ret;
if (properties == null) {
ret = new HashMap<String,Object>(0);
} else {
ret = (Map<String,Object>) (properties.clone());
}
return (Map<String,Object>) 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</code>.
*
* @param key the key of the desired property
* @return the value of the property with the specified key,
* or <code>null</code> 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
*/
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</code> 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");
// INSTANCE VARIABLES
/**
* File type name.
*/
private final String name;
/**
* File type extension.
*/
private final String extension;
// CONSTRUCTOR
/**
* 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;
}
// METHODS
/**
* Finalizes the equals method
*/
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
*/
public final int hashCode() {
if (toString() == null) {
return 0;
}
return toString().hashCode();
}
/**
* Provides the file type's name as the <code>String</code> representation
* of the file type.
* @return the file type's name
*/
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;
}
} // class Type
} // class AudioFileFormat
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