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Java javax.sound.sampled Class AudioSystem（JDK8）

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Java™ Platform
Standard Ed. 8
javax.sound.sampled

Class AudioSystem


  • public class AudioSystem
extends Object
    The AudioSystem class acts as the entry point to the sampled-audio system resources. This class lets you query and access the mixers that are installed on the system. AudioSystem includes a number of methods for converting audio data between different formats, and for translating between audio files and streams. It also provides a method for obtaining a Line directly from the AudioSystem without dealing explicitly with mixers.

    Properties can be used to specify the default mixer for specific line types. Both system properties and a properties file are considered. The sound.properties properties file is read from an implementation-specific location (typically it is the lib directory in the Java installation directory). If a property exists both as a system property and in the properties file, the system property takes precedence. If none is specified, a suitable default is chosen among the available devices. The syntax of the properties file is specified in Properties.load. The following table lists the available property keys and which methods consider them:

    Audio System Property Keys
    Property Key Interface Affected Method(s)
    javax.sound.sampled.Clip Clip getLine(javax.sound.sampled.Line.Info), getClip()
    javax.sound.sampled.Port Port getLine(javax.sound.sampled.Line.Info)
    javax.sound.sampled.SourceDataLine SourceDataLine getLine(javax.sound.sampled.Line.Info), getSourceDataLine(javax.sound.sampled.AudioFormat)
    javax.sound.sampled.TargetDataLine TargetDataLine getLine(javax.sound.sampled.Line.Info), getTargetDataLine(javax.sound.sampled.AudioFormat)
    The property value consists of the provider class name and the mixer name, separated by the hash mark ("#"). The provider class name is the fully-qualified name of a concrete mixer provider class. The mixer name is matched against the String returned by the getName method of Mixer.Info. Either the class name, or the mixer name may be omitted. If only the class name is specified, the trailing hash mark is optional.

    If the provider class is specified, and it can be successfully retrieved from the installed providers, the list of Mixer.Info objects is retrieved from the provider. Otherwise, or when these mixers do not provide a subsequent match, the list is retrieved from getMixerInfo() to contain all available Mixer.Info objects.

    If a mixer name is specified, the resulting list of Mixer.Info objects is searched: the first one with a matching name, and whose Mixer provides the respective line interface, will be returned. If no matching Mixer.Info object is found, or the mixer name is not specified, the first mixer from the resulting list, which provides the respective line interface, will be returned. For example, the property javax.sound.sampled.Clip with a value "com.sun.media.sound.MixerProvider#SunClip" will have the following consequences when getLine is called requesting a Clip instance: if the class com.sun.media.sound.MixerProvider exists in the list of installed mixer providers, the first Clip from the first mixer with name "SunClip" will be returned. If it cannot be found, the first Clip from the first mixer of the specified provider will be returned, regardless of name. If there is none, the first Clip from the first Mixer with name "SunClip" in the list of all mixers (as returned by getMixerInfo) will be returned, or, if not found, the first Clip of the first Mixerthat can be found in the list of all mixers is returned. If that fails, too, an IllegalArgumentException is thrown.

    Since:
    1.3
    See Also:
    AudioFormat, AudioInputStream, Mixer, Line, Line.Info

    • Field Detail

      • NOT_SPECIFIED

        public static final int NOT_SPECIFIED
        An integer that stands for an unknown numeric value. This value is appropriate only for signed quantities that do not normally take negative values. Examples include file sizes, frame sizes, buffer sizes, and sample rates. A number of Java Sound constructors accept a value of NOT_SPECIFIED for such parameters. Other methods may also accept or return this value, as documented.
        See Also:
        Constant Field Values

    • Method Detail

      • getMixerInfo

        public static Mixer.Info[] getMixerInfo()
        Obtains an array of mixer info objects that represents the set of audio mixers that are currently installed on the system.
        Returns:
        an array of info objects for the currently installed mixers. If no mixers are available on the system, an array of length 0 is returned.
        See Also:
        getMixer(javax.sound.sampled.Mixer.Info)

      • getMixer

        public static Mixer getMixer(Mixer.Info info)
        Obtains the requested audio mixer.
        Parameters:
        info - a Mixer.Info object representing the desired mixer, or null for the system default mixer
        Returns:
        the requested mixer
        Throws:
        SecurityException - if the requested mixer is unavailable because of security restrictions
        IllegalArgumentException - if the info object does not represent a mixer installed on the system
        See Also:
        getMixerInfo()

      • getSourceLineInfo

        public static Line.Info[] getSourceLineInfo(Line.Info info)
        Obtains information about all source lines of a particular type that are supported by the installed mixers.
        Parameters:
        info - a Line.Info object that specifies the kind of lines about which information is requested
        Returns:
        an array of Line.Info objects describing source lines matching the type requested. If no matching source lines are supported, an array of length 0 is returned.
        See Also:
        Mixer.getSourceLineInfo(Line.Info)

      • getTargetLineInfo

        public static Line.Info[] getTargetLineInfo(Line.Info info)
        Obtains information about all target lines of a particular type that are supported by the installed mixers.
        Parameters:
        info - a Line.Info object that specifies the kind of lines about which information is requested
        Returns:
        an array of Line.Info objects describing target lines matching the type requested. If no matching target lines are supported, an array of length 0 is returned.
        See Also:
        Mixer.getTargetLineInfo(Line.Info)

      • isLineSupported

        public static boolean isLineSupported(Line.Info info)
        Indicates whether the system supports any lines that match the specified Line.Info object. A line is supported if any installed mixer supports it.
        Parameters:
        info - a Line.Info object describing the line for which support is queried
        Returns:
        true if at least one matching line is supported, otherwise false
        See Also:
        Mixer.isLineSupported(Line.Info)

      • getLine

        public static Line getLine(Line.Info info)
                    throws LineUnavailableException
        Obtains a line that matches the description in the specified Line.Info object.

        If a DataLine is requested, and info is an instance of DataLine.Info specifying at least one fully qualified audio format, the last one will be used as the default format of the returned DataLine.

        If system properties javax.sound.sampled.Clip, javax.sound.sampled.Port, javax.sound.sampled.SourceDataLine and javax.sound.sampled.TargetDataLine are defined or they are defined in the file "sound.properties", they are used to retrieve default lines. For details, refer to the class description. If the respective property is not set, or the mixer requested in the property is not installed or does not provide the requested line, all installed mixers are queried for the requested line type. A Line will be returned from the first mixer providing the requested line type.

        Parameters:
        info - a Line.Info object describing the desired kind of line
        Returns:
        a line of the requested kind
        Throws:
        LineUnavailableException - if a matching line is not available due to resource restrictions
        SecurityException - if a matching line is not available due to security restrictions
        IllegalArgumentException - if the system does not support at least one line matching the specified Line.Info object through any installed mixer

      • getClip

        public static Clip getClip()
                    throws LineUnavailableException
        Obtains a clip that can be used for playing back an audio file or an audio stream. The returned clip will be provided by the default system mixer, or, if not possible, by any other mixer installed in the system that supports a Clip object.

        The returned clip must be opened with the open(AudioFormat) or open(AudioInputStream) method.

        This is a high-level method that uses getMixer and getLine internally.

        If the system property javax.sound.sampled.Clip is defined or it is defined in the file "sound.properties", it is used to retrieve the default clip. For details, refer to the class description.

        Returns:
        the desired clip object
        Throws:
        LineUnavailableException - if a clip object is not available due to resource restrictions
        SecurityException - if a clip object is not available due to security restrictions
        IllegalArgumentException - if the system does not support at least one clip instance through any installed mixer
        Since:
        1.5
        See Also:
        getClip(Mixer.Info)

      • getClip

        public static Clip getClip(Mixer.Info mixerInfo)
                    throws LineUnavailableException
        Obtains a clip from the specified mixer that can be used for playing back an audio file or an audio stream.

        The returned clip must be opened with the open(AudioFormat) or open(AudioInputStream) method.

        This is a high-level method that uses getMixer and getLine internally.

        Parameters:
        mixerInfo - a Mixer.Info object representing the desired mixer, or null for the system default mixer
        Returns:
        a clip object from the specified mixer
        Throws:
        LineUnavailableException - if a clip is not available from this mixer due to resource restrictions
        SecurityException - if a clip is not available from this mixer due to security restrictions
        IllegalArgumentException - if the system does not support at least one clip through the specified mixer
        Since:
        1.5
        See Also:
        getClip()

      • getSourceDataLine

        public static SourceDataLine getSourceDataLine(AudioFormat format)
                                        throws LineUnavailableException
        Obtains a source data line that can be used for playing back audio data in the format specified by the AudioFormat object. The returned line will be provided by the default system mixer, or, if not possible, by any other mixer installed in the system that supports a matching SourceDataLine object.

        The returned line should be opened with the open(AudioFormat) or open(AudioFormat, int) method.

        This is a high-level method that uses getMixer and getLine internally.

        The returned SourceDataLine's default audio format will be initialized with format.

        If the system property javax.sound.sampled.SourceDataLine is defined or it is defined in the file "sound.properties", it is used to retrieve the default source data line. For details, refer to the class description.

        Parameters:
        format - an AudioFormat object specifying the supported audio format of the returned line, or null for any audio format
        Returns:
        the desired SourceDataLine object
        Throws:
        LineUnavailableException - if a matching source data line is not available due to resource restrictions
        SecurityException - if a matching source data line is not available due to security restrictions
        IllegalArgumentException - if the system does not support at least one source data line supporting the specified audio format through any installed mixer
        Since:
        1.5
        See Also:
        getSourceDataLine(AudioFormat, Mixer.Info)

      • getSourceDataLine

        public static SourceDataLine getSourceDataLine(AudioFormat format,
                                               Mixer.Info mixerinfo)
                                        throws LineUnavailableException
        Obtains a source data line that can be used for playing back audio data in the format specified by the AudioFormat object, provided by the mixer specified by the Mixer.Info object.

        The returned line should be opened with the open(AudioFormat) or open(AudioFormat, int) method.

        This is a high-level method that uses getMixer and getLine internally.

        The returned SourceDataLine's default audio format will be initialized with format.

        Parameters:
        format - an AudioFormat object specifying the supported audio format of the returned line, or null for any audio format
        mixerinfo - a Mixer.Info object representing the desired mixer, or null for the system default mixer
        Returns:
        the desired SourceDataLine object
        Throws:
        LineUnavailableException - if a matching source data line is not available from the specified mixer due to resource restrictions
        SecurityException - if a matching source data line is not available from the specified mixer due to security restrictions
        IllegalArgumentException - if the specified mixer does not support at least one source data line supporting the specified audio format
        Since:
        1.5
        See Also:
        getSourceDataLine(AudioFormat)

      • getTargetDataLine

        public static TargetDataLine getTargetDataLine(AudioFormat format)
                                        throws LineUnavailableException
        Obtains a target data line that can be used for recording audio data in the format specified by the AudioFormat object. The returned line will be provided by the default system mixer, or, if not possible, by any other mixer installed in the system that supports a matching TargetDataLine object.

        The returned line should be opened with the open(AudioFormat) or open(AudioFormat, int) method.

        This is a high-level method that uses getMixer and getLine internally.

        The returned TargetDataLine's default audio format will be initialized with format.

        If the system property javax.sound.sampled.TargetDataLine is defined or it is defined in the file "sound.properties", it is used to retrieve the default target data line. For details, refer to the class description.

        Parameters:
        format - an AudioFormat object specifying the supported audio format of the returned line, or null for any audio format
        Returns:
        the desired TargetDataLine object
        Throws:
        LineUnavailableException - if a matching target data line is not available due to resource restrictions
        SecurityException - if a matching target data line is not available due to security restrictions
        IllegalArgumentException - if the system does not support at least one target data line supporting the specified audio format through any installed mixer
        Since:
        1.5
        See Also:
        getTargetDataLine(AudioFormat, Mixer.Info), AudioPermission

      • getTargetDataLine

        public static TargetDataLine getTargetDataLine(AudioFormat format,
                                               Mixer.Info mixerinfo)
                                        throws LineUnavailableException
        Obtains a target data line that can be used for recording audio data in the format specified by the AudioFormat object, provided by the mixer specified by the Mixer.Info object.

        The returned line should be opened with the open(AudioFormat) or open(AudioFormat, int) method.

        This is a high-level method that uses getMixer and getLine internally.

        The returned TargetDataLine's default audio format will be initialized with format.

        Parameters:
        format - an AudioFormat object specifying the supported audio format of the returned line, or null for any audio format
        mixerinfo - a Mixer.Info object representing the desired mixer, or null for the system default mixer
        Returns:
        the desired TargetDataLine object
        Throws:
        LineUnavailableException - if a matching target data line is not available from the specified mixer due to resource restrictions
        SecurityException - if a matching target data line is not available from the specified mixer due to security restrictions
        IllegalArgumentException - if the specified mixer does not support at least one target data line supporting the specified audio format
        Since:
        1.5
        See Also:
        getTargetDataLine(AudioFormat), AudioPermission

      • getTargetEncodings

        public static AudioFormat.Encoding[] getTargetEncodings(AudioFormat.Encoding sourceEncoding)
        Obtains the encodings that the system can obtain from an audio input stream with the specified encoding using the set of installed format converters.
        Parameters:
        sourceEncoding - the encoding for which conversion support is queried
        Returns:
        array of encodings. If sourceEncodingis not supported, an array of length 0 is returned. Otherwise, the array will have a length of at least 1, representing sourceEncoding (no conversion).

      • getTargetEncodings

        public static AudioFormat.Encoding[] getTargetEncodings(AudioFormat sourceFormat)
        Obtains the encodings that the system can obtain from an audio input stream with the specified format using the set of installed format converters.
        Parameters:
        sourceFormat - the audio format for which conversion is queried
        Returns:
        array of encodings. If sourceFormatis not supported, an array of length 0 is returned. Otherwise, the array will have a length of at least 1, representing the encoding of sourceFormat (no conversion).

      • isConversionSupported

        public static boolean isConversionSupported(AudioFormat.Encoding targetEncoding,
                                            AudioFormat sourceFormat)
        Indicates whether an audio input stream of the specified encoding can be obtained from an audio input stream that has the specified format.
        Parameters:
        targetEncoding - the desired encoding after conversion
        sourceFormat - the audio format before conversion
        Returns:
        true if the conversion is supported, otherwise false

      • getTargetFormats

        public static AudioFormat[] getTargetFormats(AudioFormat.Encoding targetEncoding,
                                             AudioFormat sourceFormat)
        Obtains the formats that have a particular encoding and that the system can obtain from a stream of the specified format using the set of installed format converters.
        Parameters:
        targetEncoding - the desired encoding after conversion
        sourceFormat - the audio format before conversion
        Returns:
        array of formats. If no formats of the specified encoding are supported, an array of length 0 is returned.

      • isConversionSupported

        public static boolean isConversionSupported(AudioFormat targetFormat,
                                            AudioFormat sourceFormat)
        Indicates whether an audio input stream of a specified format can be obtained from an audio input stream of another specified format.
        Parameters:
        targetFormat - the desired audio format after conversion
        sourceFormat - the audio format before conversion
        Returns:
        true if the conversion is supported, otherwise false

      • getAudioFileFormat

        public static AudioFileFormat getAudioFileFormat(InputStream stream)
                                          throws UnsupportedAudioFileException,
                                                 IOException
        Obtains the audio file format of the provided input stream. The stream must point to valid audio file data. The implementation of this method may require multiple parsers to examine the stream to determine whether they support it. These parsers must be able to mark the stream, read enough data to determine whether they support the stream, and, if not, reset the stream's read pointer to its original position. If the input stream does not support these operations, this method may fail with an IOException.
        Parameters:
        stream - the input stream from which file format information should be extracted
        Returns:
        an AudioFileFormat object describing the stream's audio file format
        Throws:
        UnsupportedAudioFileException - if the stream does not point to valid audio file data recognized by the system
        IOException - if an input/output exception occurs
        See Also:
        InputStream.markSupported(), InputStream.mark(int)

      • getAudioFileFormat

        public static AudioFileFormat getAudioFileFormat(URL url)
                                          throws UnsupportedAudioFileException,
                                                 IOException
        Obtains the audio file format of the specified URL. The URL must point to valid audio file data.
        Parameters:
        url - the URL from which file format information should be extracted
        Returns:
        an AudioFileFormat object describing the audio file format
        Throws:
        UnsupportedAudioFileException - if the URL does not point to valid audio file data recognized by the system
        IOException - if an input/output exception occurs

      • getAudioFileFormat

        public static AudioFileFormat getAudioFileFormat(File file)
                                          throws UnsupportedAudioFileException,
                                                 IOException
        Obtains the audio file format of the specified File. The File must point to valid audio file data.
        Parameters:
        file - the File from which file format information should be extracted
        Returns:
        an AudioFileFormat object describing the audio file format
        Throws:
        UnsupportedAudioFileException - if the File does not point to valid audio file data recognized by the system
        IOException - if an I/O exception occurs

      • getAudioInputStream

        public static AudioInputStream getAudioInputStream(InputStream stream)
                                            throws UnsupportedAudioFileException,
                                                   IOException
        Obtains an audio input stream from the provided input stream. The stream must point to valid audio file data. The implementation of this method may require multiple parsers to examine the stream to determine whether they support it. These parsers must be able to mark the stream, read enough data to determine whether they support the stream, and, if not, reset the stream's read pointer to its original position. If the input stream does not support these operation, this method may fail with an IOException.
        Parameters:
        stream - the input stream from which the AudioInputStream should be constructed
        Returns:
        an AudioInputStream object based on the audio file data contained in the input stream.
        Throws:
        UnsupportedAudioFileException - if the stream does not point to valid audio file data recognized by the system
        IOException - if an I/O exception occurs
        See Also:
        InputStream.markSupported(), InputStream.mark(int)

      • getAudioInputStream

        public static AudioInputStream getAudioInputStream(URL url)
                                            throws UnsupportedAudioFileException,
                                                   IOException
        Obtains an audio input stream from the URL provided. The URL must point to valid audio file data.
        Parameters:
        url - the URL for which the AudioInputStream should be constructed
        Returns:
        an AudioInputStream object based on the audio file data pointed to by the URL
        Throws:
        UnsupportedAudioFileException - if the URL does not point to valid audio file data recognized by the system
        IOException - if an I/O exception occurs

      • getAudioInputStream

        public static AudioInputStream getAudioInputStream(File file)
                                            throws UnsupportedAudioFileException,
                                                   IOException
        Obtains an audio input stream from the provided File. The File must point to valid audio file data.
        Parameters:
        file - the File for which the AudioInputStream should be constructed
        Returns:
        an AudioInputStream object based on the audio file data pointed to by the File
        Throws:
        UnsupportedAudioFileException - if the File does not point to valid audio file data recognized by the system
        IOException - if an I/O exception occurs

      • getAudioFileTypes

        public static AudioFileFormat.Type[] getAudioFileTypes()
        Obtains the file types for which file writing support is provided by the system.
        Returns:
        array of unique file types. If no file types are supported, an array of length 0 is returned.

      • isFileTypeSupported

        public static boolean isFileTypeSupported(AudioFileFormat.Type fileType)
        Indicates whether file writing support for the specified file type is provided by the system.
        Parameters:
        fileType - the file type for which write capabilities are queried
        Returns:
        true if the file type is supported, otherwise false

      • getAudioFileTypes

        public static AudioFileFormat.Type[] getAudioFileTypes(AudioInputStream stream)
        Obtains the file types that the system can write from the audio input stream specified.
        Parameters:
        stream - the audio input stream for which audio file type support is queried
        Returns:
        array of file types. If no file types are supported, an array of length 0 is returned.

      • isFileTypeSupported

        public static boolean isFileTypeSupported(AudioFileFormat.Type fileType,
                                          AudioInputStream stream)
        Indicates whether an audio file of the specified file type can be written from the indicated audio input stream.
        Parameters:
        fileType - the file type for which write capabilities are queried
        stream - the stream for which file-writing support is queried
        Returns:
        true if the file type is supported for this audio input stream, otherwise false

      • write

        public static int write(AudioInputStream stream,
                        AudioFileFormat.Type fileType,
                        OutputStream out)
                 throws IOException
        Writes a stream of bytes representing an audio file of the specified file type to the output stream provided. Some file types require that the length be written into the file header; such files cannot be written from start to finish unless the length is known in advance. An attempt to write a file of such a type will fail with an IOException if the length in the audio file type is AudioSystem.NOT_SPECIFIED.
        Parameters:
        stream - the audio input stream containing audio data to be written to the file
        fileType - the kind of audio file to write
        out - the stream to which the file data should be written
        Returns:
        the number of bytes written to the output stream
        Throws:
        IOException - if an input/output exception occurs
        IllegalArgumentException - if the file type is not supported by the system
        See Also:
        isFileTypeSupported(javax.sound.sampled.AudioFileFormat.Type), getAudioFileTypes()
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Java™ Platform
Standard Ed. 8

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