audiosystem.java

gcc的组建

    Mixer.Info[] infos = getMixerInfo();
    for (int i = 0; i < infos.length; ++i)
      {
        Mixer mix = getMixer(infos[i]);
        try
        {
          return mix.getLine(info);
        }
        catch (LineUnavailableException _)
        {
          // Try the next provider.
        }
      }
    throw new LineUnavailableException("no Clip available");
  }

  /**
   * Return a mixer matching the provided description.  All the providers
   * on the system are searched for a matching mixer.
   * @param info description of the mixer
   * @return the matching mixer
   * @throws IllegalArgumentException if no provider supplies a matching mixer
   */
  public static Mixer getMixer(Mixer.Info info)
  {
    Iterator i = ServiceFactory.lookupProviders(MixerProvider.class);
    while (i.hasNext())
      {
        MixerProvider prov = (MixerProvider) i.next();
        if (prov.isMixerSupported(info))
          return prov.getMixer(info);
      }
    throw new IllegalArgumentException("mixer not found");
  }

  /**
   * Return an array of descriptions of all the mixers provided on the system.
   */
  public static Mixer.Info[] getMixerInfo()
  {
    HashSet result = new HashSet();
    Iterator i = ServiceFactory.lookupProviders(MixerProvider.class);
    while (i.hasNext())
      {
        MixerProvider prov = (MixerProvider) i.next();
        Mixer.Info[] is = prov.getMixerInfo();
        for (int j = 0; j < is.length; ++j)
          result.add(is[j]);
      }
    return (Mixer.Info[]) result.toArray(new Mixer.Info[result.size()]);
  }

  /**
   * Return a source data line matching the given audio format.
   * @param fmt the audio format
   * @throws LineUnavailableException if no source data line matching
   * this format is available
   * @since 1.5
   */
  public static SourceDataLine getSourceDataLine(AudioFormat fmt)
    throws LineUnavailableException
  {
    DataLine.Info info = new DataLine.Info(SourceDataLine.class, fmt);
    Mixer.Info[] mixers = getMixerInfo();
    for (int i = 0; i < mixers.length; ++i)
      {
        Mixer mix = getMixer(mixers[i]);
        if (mix.isLineSupported(info))
          return (SourceDataLine) mix.getLine(info);
      }
    throw new LineUnavailableException("source data line not found");
  }

  /**
   * Return a target data line matching the given audio format.
   * @param fmt the audio format
   * @throws LineUnavailableException if no target data line matching
   * this format is available
   * @since 1.5
   */
  public static SourceDataLine getSourceDataLine(AudioFormat fmt,
						 Mixer.Info mixer)
    throws LineUnavailableException
  {
    DataLine.Info info = new DataLine.Info(SourceDataLine.class, fmt);
    Mixer mix = getMixer(mixer);
    if (mix.isLineSupported(info))
      return (SourceDataLine) mix.getLine(info);
    throw new LineUnavailableException("source data line not found");
  }

  /**
   * Return an array of descriptions of all the source lines matching
   * the given line description.
   * @param info description of the lines to match
   */
  public static Line.Info[] getSourceLineInfo(Line.Info info)
  {
    HashSet result = new HashSet();
    Mixer.Info[] infos = getMixerInfo();
    for (int i = 0; i < infos.length; ++i)
      {
        Mixer mix = getMixer(infos[i]);
        Line.Info[] srcs = mix.getSourceLineInfo(info);
        for (int j = 0; j < srcs.length; ++j)
          result.add(srcs[j]);
      }
    return (Line.Info[]) result.toArray(new Line.Info[result.size()]);
  }

  /**
   * Find and return a target data line matching the given audio format.
   * @param fmt the format to match
   * @throws LineUnavailableException if no matching line was found 
   * @since 1.5
   */
  public static TargetDataLine getTargetDataLine(AudioFormat fmt)
    throws LineUnavailableException
  {
    DataLine.Info info = new DataLine.Info(TargetDataLine.class, fmt);
    Mixer.Info[] mixers = getMixerInfo();
    for (int i = 0; i < mixers.length; ++i)
      {
        Mixer mix = getMixer(mixers[i]);
        if (mix.isLineSupported(info))
          return (TargetDataLine) mix.getLine(info);
      }
    throw new LineUnavailableException("target data line not found");
  }

  /**
   * Return a target data line matching the given audio format and
   * mixer.
   * @param fmt the audio format
   * @param mixer the mixer description
   * @return a target data line
   * @throws LineUnavailableException if no matching target data line was
   * found
   * @since 1.5
   */
  public static TargetDataLine getTargetDataLine(AudioFormat fmt,
						 Mixer.Info mixer)
    throws LineUnavailableException
  {
    DataLine.Info info = new DataLine.Info(TargetDataLine.class, fmt);
    Mixer mix = getMixer(mixer);
    if (mix.isLineSupported(info))
      return (TargetDataLine) mix.getLine(info);
    throw new LineUnavailableException("target data line not found");
  }

  /**
   * Given a source encoding, return an array of all target encodings to which
   * data in this form can be converted.
   * @param source the source encoding
   */
  public static AudioFormat.Encoding[] getTargetEncodings(AudioFormat.Encoding source)
  {
    HashSet result = new HashSet();
    Iterator i = ServiceFactory.lookupProviders(FormatConversionProvider.class);
    while (i.hasNext())
      {
        FormatConversionProvider prov = (FormatConversionProvider) i.next();
        if (! prov.isSourceEncodingSupported(source))
          continue;
        AudioFormat.Encoding[] es = prov.getTargetEncodings();
        for (int j = 0; j < es.length; ++j)
          result.add(es[j]);
      }
    return (AudioFormat.Encoding[]) result.toArray(new AudioFormat.Encoding[result.size()]);
  }

  /**
   * Given a source format, return an array of all the target encodings to
   * which data in this format can be converted.
   * @param source the source format
   */
  public static AudioFormat.Encoding[] getTargetEncodings(AudioFormat source)
  {
    HashSet result = new HashSet();
    Iterator i = ServiceFactory.lookupProviders(FormatConversionProvider.class);
    while (i.hasNext())
      {
        FormatConversionProvider prov = (FormatConversionProvider) i.next();
        AudioFormat.Encoding[] es = prov.getTargetEncodings(source);
        for (int j = 0; j < es.length; ++j)
          result.add(es[j]);
      }
    return (AudioFormat.Encoding[]) result.toArray(new AudioFormat.Encoding[result.size()]);
  }

  /**
   * Given a target encoding and a source audio format, return an array of all
   * matching audio formats to which data in this source format can be converted. 
   * @param encoding the target encoding
   * @param sourceFmt the source format
   */
  public static AudioFormat[] getTargetFormats(AudioFormat.Encoding encoding,
					       AudioFormat sourceFmt)
  {
    HashSet result = new HashSet();
    Iterator i = ServiceFactory.lookupProviders(FormatConversionProvider.class);
    while (i.hasNext())
      {
        FormatConversionProvider prov = (FormatConversionProvider) i.next();
        AudioFormat[] es = prov.getTargetFormats(encoding, sourceFmt);
        for (int j = 0; j < es.length; ++j)
          result.add(es[j]);
      }
    return (AudioFormat[]) result.toArray(new AudioFormat[result.size()]);
  }

  /**
   * Given a line description, return an array of descriptions of all
   * the matching target lines.
   * @param info the line description
   */
  public static Line.Info[] getTargetLineInfo(Line.Info info)
  {
    HashSet result = new HashSet();
    Mixer.Info[] infos = getMixerInfo();
    for (int i = 0; i < infos.length; ++i)
      {
        Mixer mix = getMixer(infos[i]);
        Line.Info[] targs = mix.getTargetLineInfo(info);
        for (int j = 0; j < targs.length; ++j)
          result.add(targs[j]);
      }
    return (Line.Info[]) result.toArray(new Line.Info[result.size()]);
  }

  /**
   * Return true if the currently installed providers are able to
   * convert data from the given source format to the given target encoding.
   * @param targ the target encoding
   * @param source the source format
   */
  public static boolean isConversionSupported(AudioFormat.Encoding targ,
					      AudioFormat source)
  {
    Iterator i 
      = ServiceFactory.lookupProviders(FormatConversionProvider.class);
    while (i.hasNext())
      {
        FormatConversionProvider prov = (FormatConversionProvider) i.next();
        if (prov.isConversionSupported(targ, source))
          return true;
      }
    return false;
  }

  /**
   * Return true if the currently installed providers are able to convert
   * the given source format to the given target format.
   * @param targ the target format
   * @param source the source format
   */
  public static boolean isConversionSupported(AudioFormat targ,
					      AudioFormat source)
  {
    Iterator i 
      = ServiceFactory.lookupProviders(FormatConversionProvider.class);
    while (i.hasNext())
      {
        FormatConversionProvider prov = (FormatConversionProvider) i.next();
        if (prov.isConversionSupported(targ, source))
          return true;
      }
    return false;
  }

  private static boolean isFileTypeSupported(AudioFileFormat.Type[] types,
                                             AudioFileFormat.Type type)
  {
    for (int i = 0; i < types.length; ++i)
      {
        if (types[i].equals(type))
          return true;
      }
    return false;
  }

  /**
   * Return true if the given audio file format is supported by one of
   * the providers installed on the system.
   * @param type the audio file format type
   */
  public static boolean isFileTypeSupported(AudioFileFormat.Type type)
  {
    return isFileTypeSupported(getAudioFileTypes(), type);
  }

  /**
   * Return true if the given audio file format is supported for the
   * given audio input stream by one of the providers installed on the 
   * system.
   * @param type the audio file format type
   * @param ais the audio input stream
   */
  public static boolean isFileTypeSupported(AudioFileFormat.Type type,
					    AudioInputStream ais)
  {
    return isFileTypeSupported(getAudioFileTypes(ais), type);
  }

  /**
   * Return true if some provider on the system supplies a line
   * matching the argument. 
   * @param info the line to match
   */
  public static boolean isLineSupported(Line.Info info)
  {
    Mixer.Info[] infos = getMixerInfo();
    for (int i = 0; i < infos.length; ++i)
      {
        if (getMixer(infos[i]).isLineSupported(info))
          return true;
      }
    return false;
  }

  /**
   * Write an audio input stream to the given file, using the specified
   * audio file format.  All the providers installed on the system will
   * be searched to find one that supports this operation.
   * @param ais the audio input stream to write
   * @param type the desired audio file format type
   * @param out the file to write to
   * @return the number of bytes written
   * @throws IOException if an I/O error occurs while writing
   * @throws IllegalArgumentException if the file type is not supported
   */
  public static int write(AudioInputStream ais, AudioFileFormat.Type type,
			  File out)
    throws IOException
  {
    Iterator i = ServiceFactory.lookupProviders(AudioFileWriter.class);
    while (i.hasNext())
      {
        AudioFileWriter w = (AudioFileWriter) i.next();
        if (w.isFileTypeSupported(type, ais))
          return w.write(ais, type, out);
      }
    throw new IllegalArgumentException("file type not supported by system");
  }

  /**
   * Write an audio input stream to the given output stream, using the
   * specified audio file format.  All the providers installed on the
   * system will be searched to find one that supports this operation.
   * @param ais the audio input stream to write
   * @param type the desired audio file format type
   * @param os the output stream to write to
   * @return the number of bytes written
   * @throws IOException if an I/O error occurs while writing
   * @throws IllegalArgumentException if the file type is not supported
   */
  public static int write(AudioInputStream ais, AudioFileFormat.Type type,
			  OutputStream os)
    throws IOException
  {
    Iterator i = ServiceFactory.lookupProviders(AudioFileWriter.class);
    while (i.hasNext())
      {
        AudioFileWriter w = (AudioFileWriter) i.next();
        if (w.isFileTypeSupported(type, ais))
          return w.write(ais, type, os);
      }
    throw new IllegalArgumentException("file type not supported by system");
  }
}