Head First Java Chapter 11 MiniMiniMusicApp

I am learning Java with the book Head FIrst Java second edition. Now, i am at chapter 11 and want to run the MiniMiniMusicApp.java program.
I get an error :
javax.sound.midi.MidiUnavailableException
at javax.sound.midi.MidiSystem.getDefaultDeviceWrapper(MidiSystem.java:1078)
at javax.sound.midi.MidiSystem.getReceiver(MidiSystem.java:240)
at javax.sound.midi.MidiSystem.getSequencer(MidiSystem.java:442)
at javax.sound.midi.MidiSystem.getSequencer(MidiSystem.java:348)
at MiniMiniMusicApp.play(MiniMiniMusicApp.java:10)
at MiniMiniMusicApp.main(MiniMiniMusicApp.java:45)
Caused by: java.lang.IllegalArgumentException: Requested device not installed
at javax.sound.midi.MidiSystem.getDefaultDevice(MidiSystem.java:1130)
at javax.sound.midi.MidiSystem.getDefaultDeviceWrapper(MidiSystem.java:1076)
... 5 more

I have installed Java JDK 1.6.0.21 on Ubuntu. Is this a well-known problem or do i miss some files?

Martin Jansen welcome to JR!
It's difficult to answer the question without the book, because, everyone here don't have the book right now. So, please post the question!

Ok, this is the program i have typed in from the book:

No compiler errors, but at runtime the error as i have written above.

import javax.sound.midi.*;

public class MiniMiniMusicApp
{
	public void play()
	{
		try	// take the risk, try it!
		{
			// Get a sequencer and open it
			Sequencer player = MidiSystem.getSequencer();
			player.open();
			// Make a new Sequence
			Sequence seq = new Sequence(Sequence.PPQ, 4);
			// Get a new Track from the Sequence
			Track track = seq.createTrack();
			
			// Fill the track with MidEvents and give the Sequence to the Sequencer
			ShortMessage a = new ShortMessage();
			a.setMessage(144, 1, 44, 100);
			MidiEvent noteOn = new MidiEvent(a, 1);
			track.add(noteOn);
			
			ShortMessage b = new ShortMessage();
			b.setMessage(128, 1, 44, 100);
			MidiEvent noteOff = new MidiEvent(b, 1);
			track.add(noteOff);
			
			player.setSequence(seq);
			
			// Start the Sequencer
			player.start();
		
		}
		
		catch (Exception ex) 
			// in case things don't work out, be sure to catch any problems
		{
			ex.printStackTrace();
		}
	}	// close play
	
	public static void main(String[] args)
	{
		MiniMiniMusicApp mini = new MiniMiniMusicApp();
		mini.play();
	}	// close main
}	// close class

Please => UseCodeTags when you post a code snaps! Use the EDIT button and insert the code tags there! It'll be more readable!

Your code works fine on my Windows XP machine. That makes me believe the issue is OS related. The error message says "Requested device not installed". Do you have a working sound device?

Yes, i use an Asus Eee PC 1201N with well working sound. But i think i must look further to the sound device of my netbook.

Finally I found a solution (workaround) to run my java program MiniMiniMusicApp on Ubuntu. It seems that Java 1.6 don't support PulseAudio, the audiodevice is already opened by another application or it is a permission problem .
With the command: padsp java MiniMiniMusicApp it works!

(padsp starts the specified program and redirects its access to OSS compatible audio devices (/dev/dsp and auxiliary devices) to a PulseAudio sound server).

Moved to Java in General.