No, it cannot. Here is source adapted from an answer to Adjusting master volume on coderanch. The source iterates the available lines, checks if they have a control of the right type, and if so, puts them in a GUI attached to a JSlider
import java.awt.*;
import javax.swing.*;
import javax.sound.sampled.*;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
public class SoundMixer {
public Component getGui() {
JPanel gui = new JPanel(new GridLayout(0,1));
Mixer.Info[] mixers = AudioSystem.getMixerInfo();
System.out.println(
"There are " + mixers.length + " mixer info objects");
for (Mixer.Info mixerInfo : mixers) {
System.out.println("mixer name: " + mixerInfo.getName());
Mixer mixer = AudioSystem.getMixer(mixerInfo);
Line.Info[] lineInfos = mixer.getSourceLineInfo();
for (Line.Info lineInfo : lineInfos) {
System.out.println(" Line.Info: " + lineInfo);
try {
Line line = mixer.getLine(lineInfo);
FloatControl volCtrl = (FloatControl)line.getControl(
FloatControl.Type.MASTER_GAIN);
VolumeSlider vs = new VolumeSlider(volCtrl);
gui.add( new JLabel(volCtrl.toString()) );
gui.add( vs.getVolume() );
System.out.println(
" volCtrl.getValue() = " + volCtrl.getValue());
} catch (LineUnavailableException e) {
e.printStackTrace();
} catch (IllegalArgumentException iaEx) {
System.out.println(" " + iaEx);
}
}
}
return gui;
}
public static void main(String[] args) {
Runnable r = new Runnable() {
@Override
public void run() {
SoundMixer sm = new SoundMixer();
Component c = sm.getGui();
JOptionPane.showMessageDialog(null, c);
}
};
// Swing GUIs should be created and updated on the EDT
// http://docs.oracle.com/javase/tutorial/uiswing/concurrency/initial.html
SwingUtilities.invokeLater(r);
}
}
class VolumeSlider {
JSlider volume;
VolumeSlider(final FloatControl volumeControl) {
volume = new JSlider(
(int) volumeControl.getMinimum() * 100,
(int) volumeControl.getMaximum() * 100,
(int) volumeControl.getValue() * 100);
ChangeListener listener = new ChangeListener() {
@Override
public void stateChanged(ChangeEvent e) {
float val = volume.getValue() / 100f;
volumeControl.setValue(val);
System.out.println(
"Setting volume of " + volumeControl.toString() +
" to " + val);
}
};
volume.addChangeListener(listener);
}
public JSlider getVolume() {
return volume;
}
}
On this Windows 7 machine I get two controls, both from the "Java Sound Audio Engine". Neither has any effect on the current system volume.
run:
There are 4 mixer info objects
mixer name: Primary Sound Driver
Line.Info: interface SourceDataLine supporting 8 audio formats, and buffers of at least 32 bytes
java.lang.IllegalArgumentException: Unsupported control type: Master Gain
Line.Info: interface Clip supporting 8 audio formats, and buffers of at least 32 bytes
java.lang.IllegalArgumentException: Unsupported control type: Master Gain
mixer name: Speakers (VIA High Definition Audio)
Line.Info: interface SourceDataLine supporting 8 audio formats, and buffers of at least 32 bytes
java.lang.IllegalArgumentException: Unsupported control type: Master Gain
Line.Info: interface Clip supporting 8 audio formats, and buffers of at least 32 bytes
java.lang.IllegalArgumentException: Unsupported control type: Master Gain
mixer name: Java Sound Audio Engine
Line.Info: interface SourceDataLine supporting 8 audio formats
volCtrl.getValue() = 0.0
Line.Info: interface Clip supporting 8 audio formats, and buffers of 0 to 4194304 bytes
volCtrl.getValue() = 0.0
mixer name: Port Speakers (VIA High Definition A
Setting volume of Master Gain with current value: 0.0 dB (range: -80.0 - 13.9794) to 0.0
Setting volume of Master Gain with current value: 0.0 dB (range: -80.0 - 13.9794) to -0.41
Setting volume of Master Gain with current value: 0.0 dB (range: -80.0 - 13.9794) to -0.68
...
Swap FloatControl.Type.MASTER_GAIN for FloatControl.Type.VOLUME to see.. no controls.
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