posted 20 years ago
My assignment is similar. Basically, if the interface has a method, you need to provide implementation for the classes that implement the interface. Otherwise, you would have to declare the implementing class abstract.
If the assignment does not tell you that you must invoke the implemented method, then you don't have to unless you need to invoke such a method to satisfy another "must". Doing more than is required give you no extra points, but it sure gives an opportunity for the judges to knock points off! I wouldn't be surprised if doing extra loses points because "extra" equals "scope creep"...
Give a man a fish, he'll eat for one day. Teach a man to fish, he'll drink all your beer.
Cheers, Jeff (SCJP 1.4 all those years ago...)