COSC 1030: Assignment #1

Abstract Classes/Testing

Due: October 5, 2000, 1 pm

Part A: The CombinationLock Class

You are to implement a class called CombinationLock. Its job is to represent a combination lock.

The assignment can be found in /cs/course/1030/a1 on Ariel. The abstract class CombinationLock has already been created with the required abstract methods and can be found in It constains a description of what must be done. You are required to extend it and implement the methods. Note that you must supply a constructor that takes the combination as its argument as directed. You are also given a driver program,, to test your implementation.

Part B: Black-Box Testing

You are also required to do black-box testing of several classes: CombinationLock1.class, CombinationLock2.class, CombinationLock3.class, CombinationLock4.class, and CombinationLock5.class. They are genuine implementations of the CombinationLock class but may have one or more errors. By black-box testing, come up with a theory of the error(s) in each of these implementations.  Give a description that is as precise as possible of (1) what errors you find and (2) what the possible causes of the error(s) may be.

Remember to include a copy of the marking sheet supplied as the cover page of your report.

Revised: Sept. 25, 2000