Hi, I've a .class file which I've compiled from my .java file. I tried to make .desktop file, though I've very little, little than you might be thinking. I just copied the instructions given in the wiki about .desktop file except the Exec, here I entered as follows:
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Exec=cacao -cp /usr/share/java/swt.gtk.jar:. /media/mmc1/myApplication
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To be honest, I don't know what I'm doing. I just thought it would interprete it as a command in the xterm. So, result is obvious, nothing happens when I click the icon in the application list. I would be grateful if someone could guide me through it. Thanks

I copied and pasted the info from various threads to the wiki.
I take it from the command line, "cacao -cp /usr/share/java/swt.gtk.jar:. /media/mmc1/myApplication" launches the .class file? do you have myApplication.class ?

The only help I could offer is to suggest viewing the other .desktop files for some other options, like replacing Exec= to Command= (speculating) or something of that sort.

Because java loads classes, and not class files, I believe you want yout exec line to look like this: This will look in any directories in the classpath parameter (in this case, /usr/share/java/swt.gtk.jar, ., and /media/mmc1) for a .class file containing a class named myApplication.

As a side note, you might need chmod +x on your class file, which the sd card won't allow (it's mounted wit noexec), so you might have to either edit /etc/fstab to remove noexec, or move the class file to somewhere in the root filesystem, and chmod +x it.

Or, was your original command working fine in xterm? I've been wrong before...