If, like me, you've got a newer version of Java installed on your system and couldn't run ModelChecker.jar without issues, follow this cheeky li'l guide to get set up.
Firstly, you're gonna need to get Java 1.8 if you don't already. This can be found here. Unfortunately, you need to make an Oracle account to download it :(
After installing, run /usr/libexec/java_home -V - this should list all of the versions you have installed. Check that there is 1.8.0_221, x86-64: "Java SE 8" listed.
Once you've got that sussed, go into your SWEN324HandBuild folder.