Class cast exception when trying to get a control on the "Wave" mixer

Question

I am trying to get a control over the level of the Wave mixer. I can get the master, but I need a bit finer control than that. I think I have one, and it compiles, but I get a classCast exception at runtime:
volumeSearch:
for (int i = 0; i < mixerInfo.length; i++)
    Mixer.Info info = mixerInfo;
mixer = AudioSystem.getMixer(info);
System.out.println("info.getName() = " + info.getName());
if (mixer.isLineSupported(Port.Info.SPEAKER))
System.out.println(info.getName() + " supports a speaker");
lineOut = (Port) mixer.getLine(Port.Info.SPEAKER);
lineOut.open();
Control[] controls = lineOut.getControls();
System.out.println("Supported controls on the speaker:");
for (int j = 0; j < controls.length; j++)
Control control = controls[j];
System.out.println("\tcontrol.toString() = " + control.toString());
System.out.println("\tcontrol.getType() = " + control.getType());
if (control.getType().toString().contains("Wave") || control.getType().toString().contains("WAVE")||control.getType().toString().contains("wave")){
volumeControl = (FloatControl)controls[j];
break volumeSearch;
I get the class cast exception when I try to get the control at :volumeControl = (FloatControl)controls[j];
volumeControl is declared earlier in the class as a FloatControl.
Any tips?                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               

Answer 1

Hey guys, thanks for replying to my post!
Here's the rub: I am able to use the method you are describing, but it gives me control over the wrong mixer.
On the main mixer, it gives me control over the "Master" volume, which means that in addition to the wave output, it also controls every other output simultaneously, such as the Mic output. I am trying to get control of the "Wave" output. When adjusting the Wave out, it only effects digital audio output, but leaves the analog outputs (like the Mic volume) alone.
Now, when I call the complete method:
    private void initVolumeControl()
        Port lineOut;
        FloatControl vol;
        Mixer mixer;
        Mixer.Info[] mixerInfo = AudioSystem.getMixerInfo();
        try
            volumeSearch:
            for (int i = 0; i < mixerInfo.length; i++)
                Mixer.Info info = mixerInfo;
mixer = AudioSystem.getMixer(info);
System.out.println("info.getName() = " + info.getName());
if (mixer.isLineSupported(Port.Info.SPEAKER))
System.out.println(info.getName() + " supports a speaker");
lineOut = (Port) mixer.getLine(Port.Info.SPEAKER);
lineOut.open();
At this point, if I wanted to control the master volume, I would get the volume control over
the main mixer here
by calling
vol = (FloatControl) lineOut.getControl(FloatControl.Type.VOLUME);
But the problem is that gives me control over the main, and not the wave volume.
So, on the "lineOut", let's query it for all of the different controls available
Control[] controls = lineOut.getControls();
System.out.println("Supported controls on the speaker:");
for (int j = 0; j < controls.length; j++)
Control control = controls[j];
System.out.println("\tcontrol.toString() = " + control.toString());
System.out.println("\tcontrol.getType() = " + control.getType());
if (control.getType().toString().contains("Wave") || control.getType().toString().contains("WAVE") || control.getType().toString().contains("wave"))
volumeControl = (FloatControl)control;
break volumeSearch;
} catch (Exception e)
System.err.println("There was an error while trying to get a volume control");
e.printStackTrace();
And my output from this is:info.getName() = Primary Sound Driver
info.getName() = Realtek HD Audio output
info.getName() = Primary Sound Capture Driver
info.getName() = Realtek HD Audio Input
info.getName() = Java Sound Audio Engine
info.getName() = Port Realtek HD Audio output
Port Realtek HD Audio output supports a speaker
Speaker volume = 0.5000076
Supported controls on the speaker:
control.toString() = Volume with current value: 0.5000076 (range: 0.0 - 1.0)
control.getType() = Volume
control.toString() = Balance with current value: 3.0517345E-5 (range: -1.0 - 1.0)
control.getType() = Balance
control.toString() = Mute Control with current value: false
control.getType() = Mute
control.toString() = Wave Control containing Volume, Balance, and Mute Controls.
control.getType() = Wave
but I also get the exception:There was an error while trying to get a volume control
java.lang.ClassCastException: com.sun.media.sound.PortMixer$CompCtrl
at audiotools.AudioPlayer.initVolumeControl(AudioPlayer.java:236)
at audiotools.AudioPlayer.<init>(AudioPlayer.java:102)
at audiotools.AudioPlayer.getInstance(AudioPlayer.java:59)
at gui.windowmanager.WindowManager.run(WindowManager.java:208)
at java.lang.Thread.run(Thread.java:595)
So, as you can see, when I query the line that supports SPEAKER, it says it has an additional item (Mixer? Line?) called "Wave Control" that also has it's own Volume, Balance and Mute controls.
I need to get the Volume control associated with the "Wave", not the one associated with the "Master". The Master provides too general of a control on the system mixer.
Edited by: J_Y_C on Oct 30, 2008 6:09 AM