Tojvm is a "toy VM", an attempt to implement a JVM in Go. Currently it's rather incomplete, and many instructions are missing. However, it can do basic arithmetics, create objects, call methods and modify their fields. I hope to add more instructions later, but if you get interested in how it works - PRs and comments are always welcome!
This should not be used in production, the performance will suffer anyway. Only use for didactic purposes.