AudioSystem.java 文件源码

/**
 * Obtains an audio input stream of the indicated format, by converting the
 * provided audio input stream.
 *
 * @param  targetFormat the desired audio format after conversion
 * @param  sourceStream the stream to be converted
 * @return an audio input stream of the indicated format
 * @throws IllegalArgumentException if the conversion is not supported
 * @throws NullPointerException if {@code targetFormat} or
 *         {@code sourceStream} are {@code null}
 * @see #getTargetEncodings(AudioFormat)
 * @see #getTargetFormats(AudioFormat.Encoding, AudioFormat)
 * @see #isConversionSupported(AudioFormat, AudioFormat)
 * @see #getAudioInputStream(AudioFormat.Encoding, AudioInputStream)
 */
public static AudioInputStream getAudioInputStream(AudioFormat targetFormat,
                                                   AudioInputStream sourceStream) {
    if (sourceStream.getFormat().matches(targetFormat)) {
        return sourceStream;
    }

    List<FormatConversionProvider> codecs = getFormatConversionProviders();

    for(int i = 0; i < codecs.size(); i++) {
        FormatConversionProvider codec = codecs.get(i);
        if(codec.isConversionSupported(targetFormat,sourceStream.getFormat()) ) {
            return codec.getAudioInputStream(targetFormat,sourceStream);
        }
    }

    // we ran out of options...
    throw new IllegalArgumentException("Unsupported conversion: " + targetFormat + " from " + sourceStream.getFormat());
}