AudioSystem.java 文件源码

/**
 * Obtains the encodings that the system can obtain from an audio input
 * stream with the specified encoding using the set of installed format
 * converters.
 *
 * @param  sourceEncoding the encoding for which conversion support is
 *         queried
 * @return array of encodings. If {@code sourceEncoding} is not supported,
 *         an array of length 0 is returned. Otherwise, the array will have
 *         a length of at least 1, representing {@code sourceEncoding}
 *         (no conversion).
 * @throws NullPointerException if {@code sourceEncoding} is {@code null}
 */
public static AudioFormat.Encoding[] getTargetEncodings(AudioFormat.Encoding sourceEncoding) {
    Objects.requireNonNull(sourceEncoding);

    List<FormatConversionProvider> codecs = getFormatConversionProviders();
    Vector<AudioFormat.Encoding> encodings = new Vector<>();

    AudioFormat.Encoding encs[] = null;

    // gather from all the codecs
    for(int i=0; i<codecs.size(); i++ ) {
        FormatConversionProvider codec = codecs.get(i);
        if( codec.isSourceEncodingSupported( sourceEncoding ) ) {
            encs = codec.getTargetEncodings();
            for (int j = 0; j < encs.length; j++) {
                encodings.addElement( encs[j] );
            }
        }
    }
    if (!encodings.contains(sourceEncoding)) {
        encodings.addElement(sourceEncoding);
    }

    return encodings.toArray(new AudioFormat.Encoding[encodings.size()]);
}