MultiClip.java 文件源码

/**
 * Plays the clip with the specified volume.
 * @param volume the volume the play at
 * @param listener the line listener
 * @throws LineUnavailableException if a clip object is not available or
 *         if the line cannot be opened due to resource restrictions
 */
public void start(float volume, LineListener listener) throws LineUnavailableException {
    Clip clip = getClip();
    if (clip == null)
        return;

    // PulseAudio does not support Master Gain
    if (clip.isControlSupported(FloatControl.Type.MASTER_GAIN)) {
        // set volume
        FloatControl gainControl = (FloatControl) clip.getControl(FloatControl.Type.MASTER_GAIN);
        float dB = (float) (Math.log(volume) / Math.log(10.0) * 20.0);
        gainControl.setValue(dB);
    }

    if (listener != null)
        clip.addLineListener(listener);
    clip.setFramePosition(0);
    clip.start();
}