A comprehensive approach for the development of modular software architecture description languages

Abstract

Research over the past decade has revealed that modeling software architecture at the level of components and connectors is useful in a growing variety of contexts. This has led to the development of a plethora of notations for representing software architectures, each focusing on different aspects of the systems being modeled. In general, these notations have been developed without regard to reuse or extension. This makes the effort in adapting an existing notation to a new purpose commensurate with developing a new notation from scratch. To address this problem, we have developed an approach that allows for the rapid construction of new architecture description languages (ADLs). Our approach is unique because it encapsulates ADL features in modules that are composed to form ADLs. We achieve this by leveraging the extension mechanisms provided by XML and XML schemas. We have defined a set of generic, reusable ADL modules called xADL 2.0, useful as an ADL by itself, but also extensible to support new applications and domains. To support this extensibility, we have developed a set of reflective syntax-based tools that adapt to language changes automatically, as well as several semantically-aware tools that provide support for advanced features of xADL 2.0. We demonstrate the effectiveness, scalability, and flexibility of our approach through a diverse set of experiences. First, our approach has been applied in industrial contexts, modeling software architectures for aircraft software and spacecraft systems. Second, we show how xADL 2.0 can be extended to support the modeling features found in two different representations for modeling product-line architectures. Finally, we show how our infrastructure has been used to support its own development. The technical contribution of our infrastructure is augmented by several research contributions: the first decomposition of an architecture description language into modules, insights about how to develop new language modules and a process for integrating them, and insights about the roles of different kinds of tools in a modular ADL-based infrastructure.

On the Composition and Reuse of Viewpoints across Architecture Frameworks

“…Other "classical" ADLs (from the 1990s) include Darwin [17], RAPIDE [18] and Wright. More recent ADLs can be quite elaborate with numerous model kinds and viewpoints (such as AADL [19], ArchiMate [20], SysML and xADL [21]). …”

Model-Driven Techniques to Enhance Architectural Languages Interoperability

“…Language extensibility in the software architecture domain has been adopted in the xADL [9] XML-based architecture description language (based on XML extension mechanisms), in AADL [10] (through its annexes), in UML (with its profiles), and in our approach for ALs interoperability named DUALLY [7]. However, DUALLY, which is at the best of our knowledge the most mature framework to support interoperability among various ALs, has shown a certain number of shortcomings.…”

Good Architecture = Good (ADL + Practices)

“…Throughout a project, it can serve as a baseline against which the various stakeholders analyze, understand, build their decisions, and evaluate the software [1]. The languages (Acme [2], xADL [3], ByADL [4], UML as an ADL [5]) used to elaborate architectures highlight concepts (such as connectors, components, etc.) that meet two requirements: (i) be enough expressive to represent all targeted systems, and (ii) allow the architect to focus his attention on key issues such as information hiding, coupling, cohesion, precision, etc.…”