Java SourceDataLine.getControl方法代碼示例

import javax.sound.sampled.SourceDataLine; //導入方法依賴的package包/類
/**
 * Creates a new {@code StreamingPlayback}. StreamingPlayback objects will
 * always be created by their associated StreamingAudio object.
 *
 * @param audio
 *            The {@code Audio} that created this {@code StreamingPlayback}.
 * @param audioInStream
 *            The {@code AudioInputStream} used by this
 *            {@code StreamingPlayback}.
 * @param instanceID
 *            The {@code instanceID} of this {@code StreamingPlayback}.
 */
protected StreamingPlayback(Audio audio, AudioInputStream audioInStream,
		long instanceID) {

	super(audio, instanceID);
	this.audioInStream = audioInStream;

	AudioFormat audioFormat = audioInStream.getFormat();
	DataLine.Info info = new DataLine.Info(SourceDataLine.class,
			audioFormat);
	try {
		line = (SourceDataLine) AudioSystem.getLine(info);
		if (line != null) {
			line.open(audioFormat);
		}
		if (line.isControlSupported(FloatControl.Type.MASTER_GAIN)) {
			volCtrl = (FloatControl) line
					.getControl(FloatControl.Type.MASTER_GAIN);
		} else {
			logger.warning("Master-Gain control is not supported."
					+ " Volume will be fixed at the default level.");
		}
	} catch (LineUnavailableException ex) {
		ex.printStackTrace();
	}
}
 

import javax.sound.sampled.SourceDataLine; //導入方法依賴的package包/類
private void initSound() {
    if (quiet == null) {
        quiet = new byte[WAVE_LEN];
    }
    if (buffer == null) {
        byte[] buf = new byte[WAVE_LEN];
        double f1 = 0;
        for (int i = 0, n = WAVE_LEN; i < n; i++) {
            f1 = Math.sin(i * 3.141592 * 2 / WAVE_LEN) * 40;
            f1 += Math.sin(i * 3.141592 * 4 / WAVE_LEN) * 30;
            buf[i] = (byte) (f1);
        }
        buffer = buf;
    }
    if (soundEvent == null) {
        soundEvent = new TimeEvent(0, "Beeper") {
            public void execute(long t) {
                if (isSoundEnabled) {
                    ioTick(t);
                    cpu.scheduleCycleEvent(this, cpu.cycles + 1000);
                }
            }
        };
    }
    AudioFormat af = new AudioFormat(SAMPLE_RATE, 8, 1, true, false);
    DataLine.Info dli = new DataLine.Info(SourceDataLine.class, af, 16384);
    try {
        dataLine = (SourceDataLine) AudioSystem.getLine(dli);
        if (dataLine == null) {
            logw(WarningType.EMULATION_ERROR, "No audio data line available");
        } else {
            dataLine.open(dataLine.getFormat(), 16384);
            volume = (FloatControl) dataLine.getControl(FloatControl.Type.MASTER_GAIN);
        }
    } catch (Exception e) {
        logw(WarningType.EMULATION_ERROR, "Could not get audio data line: " + e);
    }
    if (dataLine != null) {
        isSoundEnabled = true;
        dataLine.start();
    }
}
 

import javax.sound.sampled.SourceDataLine; //導入方法依賴的package包/類
public static void playAudioFile(File file, int playDurationMillis)
{
	try
	{
		// Get AudioInputStream from given file.	
		AudioInputStream compressedInput = AudioSystem.getAudioInputStream(file);
		AudioInputStream decodedInput = null;
		if (compressedInput != null)
		{
			AudioFormat baseFormat = compressedInput.getFormat();
			AudioFormat format = new AudioFormat(AudioFormat.Encoding.PCM_SIGNED, baseFormat.getSampleRate(), 16,
					baseFormat.getChannels(), baseFormat.getChannels() * 2, baseFormat.getSampleRate(), false);
			// Get AudioInputStream that will be decoded by underlying VorbisSPI
			decodedInput = AudioSystem.getAudioInputStream(format, compressedInput);

			int oneSecondBytes = (int) Math.ceil(format.getFrameSize() * format.getFrameRate());
			int fadeOutDurationBytes = oneSecondBytes / 20;
			int playDurationBytes;
			if (playDurationMillis <= 0)
				playDurationBytes = Integer.MAX_VALUE;
			else
				playDurationBytes = oneSecondBytes * playDurationMillis / 1000;

			byte[] data = new byte[1024];
			SourceDataLine line = (SourceDataLine) AudioSystem.getLine(new DataLine.Info(SourceDataLine.class,
					format));
			line.open(format);

			FloatControl gainControl = (FloatControl) line.getControl(FloatControl.Type.MASTER_GAIN);
			float initialGain = gainControl.getValue();

			// Start
			line.start();
			int bytesRead;
			int totalBytes = 0;
			while ((bytesRead = decodedInput.read(data, 0, data.length)) != -1)
			{
				totalBytes += bytesRead;
				int playedBytes = totalBytes;
				if (totalBytes >= playDurationBytes)
				{
					bytesRead -= totalBytes - playDurationBytes;
					playedBytes = playDurationBytes;
				}

				if (playDurationBytes - playedBytes < fadeOutDurationBytes)
				{
					float fadePct = ((float) (playDurationBytes - playedBytes)) / fadeOutDurationBytes;
					gainControl.setValue(initialGain * fadePct + gainControl.getMinimum() * (1.0f - fadePct));
				}

				line.write(data, 0, bytesRead);

				if (totalBytes >= playDurationBytes)
					break;
			}
			// Stop
			line.drain();
			gainControl.setValue(initialGain);
			line.stop();
			line.close();
			decodedInput.close();
			compressedInput.close();
		}
	}
	catch (Exception e)
	{
		e.printStackTrace();
	}
}