Multiple Viewpoint Contract-Based Specification and Design

Contracts for System Design

“…This calls for including non-functional characteristics as part of the component interface specifications, which is best achieved by using multiple viewpoints [40,46,42]. Contract-based design supports multiple viewpoints by giving a mathematically precise answer to what it means to fuse them.…”

“…Chapter 5 deals with Assume/Guarantee contracts [40,46]. This framework is the most straightforward instance of the meta-theory.…”

Providing tool support for specifying safety-critical systems by enforcing syntactic contract conditions

“…This support is provided by applying the work in [6,68,73,75,76] that present a formal and general contracts [53] theory for modeling and specifying systems.…”

“…These tasks (I)-(IV) are also described in FuSa standards; however, the fact is that in contracts theory [6,68,73,75,76], these tasks are given formal semantics, i.e., interpretations in formal (mathematical) conditions. The present paper capitalizes on this fact by considering the support that can be provided for tasks (I)-(IV) by having a tool that evaluates these formal contract conditions.…”

“…Despite the fact that formal representations have several advantages over non-formal ones, formal languages are difficult to use by non-experts [23] and in industrial practice, 'overcoming the burden of formalization is a major challenge' [10]. Therefore, instead of focusing on enforcing all of the contract conditions in [6,68,73,75,76], the present paper instead identifies necessary conditions of the formal interpretations of tasks (I)-(IV) where these conditions can be evaluated even when requirements and architectures are not represented formally; in the following, such necessary conditions will be called syntactic contract conditions.…”