Spotlet is an "old" class included in kjava package that was used to create j2me applications for the Palm OS.I think you shouldn't be using it nowdays because it is a little old fashioned.It was used when all this world of j2me started, to help people develop java applications for handhelds runinng Palm OS.
Instead you should be using the Midlet class because the MIDP profile is oriented for this type of devices.