JAVA - Microprogram

Calling all geeks!
I really need someone's help with this, I am a first year student (or freshman as i believe they are called 'across the pond') majoring in Maths and doing a bit of Java programming aswell. I have been set an assignment by my lecturer and I haven't got a clue how to get started. The problem is;

'Given a stack of 3 operands and 2 operations, evaluate in Java the way that a simple microprogram would work to execute this instruction.
e.g. (5*(3-2)).'

At best my Java knowledge is limited, so any help would be appreciated!