GUI does not work when opened via file explorer

[iimog]

As reported by a user:

(i) GUI started via terminal:

cd /home/user/bcgTree/bcgTreeGUI
java -jar bcgTree.jar

-> bcgTree GUI starts
-> in bcgTree GUI: check for dependencies is ok

(ii) GUI started via file explorer (nautilus):
Home - bcgTree - bcgTree GUI -> double click on bcgTree.jar
-> bcgTree GUI starts
-> in bcgTree GUI: check for dependencies is not (!) ok

[iimog]

I assume that this has something to do with the implicit working directory set when the jar is started via nautilus. Unfortunately I could not quickly reproduce because jar files are not associated with java in my setup so double clicking them in nautilus does not start bcgTree at all.