Can anyone tell me how to build a start script for a java game for Mac OS X?

I just created a game.command file which contains just this one line:
java -Djava.library.path=lib/lwjgl/native/macosx:lib -Dorg.lwjgl.opengl.Display.allowSoftwareOpenGL=true -jar game.jar


If I enter this in a console window the game runs as it should, but when launching (double clicking) this .command file I get this error:
Unable to access jarfile game.jar


I thought it would have something to do with paths, so I changed the line to this:
java -Djava.library.path=/Users/Spezi/Desktop/game/lib/lwjgl/native/macosx:/Users/Spezi/Desktop/game/lib -Dorg.lwjgl.opengl.Display.allowSoftwareOpenGL=true -jar /Users/Spezi/Desktop/game/game.jar


This works, but how can this be run without setting absolute paths?

Or is there another (maybe better) way to easily run it?

I'm at work right now and not near any Macs (unfortunately), but take a look at Eclipse.app and see how they do it. They set it up quite well to run as a "native" app.

You should be able to right click on Eclipse.app and select something like "open package contents" to see what's inside (foo.app is really a folder that the OS presents as a single entity).

In there should be info.plist and a few other things that allow a Java app to be launched just like a native one.

Thanks for the idea with the .app.

After hours of trying to build it on my own I googled a bit and found out about a programm called 'Jar Bundler' which made creating the structure an easy step.

So I got it double clickable running now, although some tiny hidden parameter to the command line would had also satisfied me.