A NAVIGATIONAL DATA MODEL FOR OBJECT MODELING TECHNIQUE DEVELOPMENT ENVIRONMENT

Extant tools supporting Object Modeling Technique (OMT) have a serious drawback that they fail to capture a lot of relationships inherently existing among design objects. This drawback may not only disallow des igners to freely navigate the relationships but also make it difficult to automatically enforce integrity constraints derived from the relat ionships. To overcome the drawback, we propose a navigational data mod el called FONASSE (FOur-dimensional NAvigation Spaceship for Software Engineering), The data model captures four structural relationships am ong design objects: part of, the other development stage of, the other representation of, and version of. A considerable part of structural semantics the design objects inherently have, can be well captured wit h the relationships. Since the four relationships are mutually exclusi ve with each other, designers may navigate a set of design objects in a four-dimensional space. Supporting the relationships at system level also entails the automatic enforcement of corresponding integrity con straints, We identified four integrity constraints, each of which is d erived from one of the four relationships. In this paper, FONASSE is f ully developed as a model suitable to the four-dimensional navigation. As a first step towards such development, a navigation function is de fined to formally specify the semantics of queries related with the na vigation. The queries, which turn out to be a specification of navigat ion paths, can be uniformly formulated by the combination of the navig ation functions. The integrity constraints corresponding to the relati onships are also expressed in terms of the navigation functions. Final ly, we provide a scenario to explain the navigational characteristic o f our model. (C) 1998 Elsevier Science Inc. All rights reserved.