Combining Problem Frames and UML in the Description of Software Requirements

Problem frames are a sound and convenient approach to requirements modeling. Nevertheless, they are far less popular than other less rigorous approaches. One reason is that they employ a notation that is neither very appealing nor easy to use. The problem frames notation is sufficiently different from other development languages –especially UML– to create an “impedance mismatch”: using problem frames to describe requirements does not help the transition to the design phase, makes it difficult for programmers to fully comprehend requirements, and does not favor traceability. As a consequence, problem frames are rarely adopted in software development processes employing UML as a design language. UML itself provides a linguistic support for requirements modeling, which however suffers from several limitations, especially as far as precision and formality are concerned. The goal of this paper is to combine problem frames and UML in order to both improving the linguistic support for problem frames –while preserving the underlying concepts– and to improve the UML development practice by introducing the problem frames approach, making it seamlessly applicable in the context of the familiar UML language.