An approach to representing and utilizing specification pattern knowledge for computer-aided formalization of requirements

Abstract

Formalizing requirements in formal specifications usually requires high skills for abstraction and experience in using the formal notation in which the specification is written. This poses a challenge to many practitioners who have to deal with realistic systems within the required schedule and budget. To handle this challenge, a pattern system has been proposed for computer-aided construction of formal expressions. It organizes various inter-related patterns on computer, each of which deals with the formalization of a kind of informal ideas. But how to represent such knowledge to facilitate its automatic utilization and maintenance remains a problem. This paper presents an approach to representing and utilizing the pattern knowledge on the basis of a formal definition of the pattern system. The application process of the pattern system is described in HFSM (Hierarchical Finite State Machine) and treated as knowledge. By performing a proposed algorithm, necessary information can be retrieved from the HFSM for capturing informal requirements and automatically generating formal expressions. We also describe a prototype tool that implements the approach and present a case study on modeling a bank data management system.