Object-Oriented Requirements: a Unified Framework for Specifications, Scenarios and Tests

TL;DR

This paper proposes a unified object-oriented framework for requirements, scenarios, and tests, aiming to combine the practicality of use cases with the reusability and extendibility of OO principles.

Contribution

It introduces a generalized class concept that encompasses use cases, user stories, and test artifacts, bridging procedural and object-oriented requirements.

Findings

Unified framework enables requirements to reflect stakeholder views and support evolution.

Class concept generalizes scenarios, use cases, and test cases within an OO paradigm.

Framework facilitates reuse and extendibility of requirements artifacts.

Abstract

A paradox of requirements specifications as dominantly practiced in the industry is that they often claim to be object-oriented (OO) but largely rely on procedural (non-OO) techniques. Use cases and user stories describe functional flows, not object types. To gain the benefits provided by object technology (such as extendibility, reusability, reliability), requirements should instead take advantage of the same data abstraction concepts - classes, inheritance, information hiding - as OO design and OO programs. Many people find use cases and user stories appealing because of the simplicity and practicality of the concepts. Can we reconcile requirements with object-oriented principles and get the best of both worlds? This article proposes a unified framework. It shows that the concept of class is general enough to describe not only "objects" in a narrow sense but also scenarios such as use cases and user stories and other important artifacts such as test cases and oracles. Having a single framework opens the way to requirements that enjoy the benefits of both approaches: like use cases and user stories, they reflect the practical views of stakeholders; like object-oriented requirements, they lend themselves to evolution and reuse.