This was written as a personal exercice after watching this great presentation about VM's by Terence Parr.
NOTE: I built this in order to learn the basics of VM's, and learn some Java while I was at it. It's an extremely simplistic implementation!
There's a makefile. In the project root, simply run make to build, or make run to build and run. make clean cleans up the built objects.
It handles 18 basic bytecode instructions, including calling a function whilst preserving state. Check out vm.Bytecode to see all 18 Instructions.
To run a program, simply create an int[] array with any instruction set and hand it over to the VM. Setting the trace property to true will print the stack trace as the program runs. See the main function in vm.Test for more information.