Component-based specification of software architecture constraints

Abstract

Component-based software engineering provides for developers the ability to easily reuse and assemble software entities to build complex software. Component-based specification of software functional characteristics has been and is largely addressed, however this is not yet the case for what concerns software non-functional characteristics. In this paper, we propose a new way to express component-based software non-functional documentation, and we will focus more specifically on architecture constraints which formalize parts of architecture decisions, as executable, customizable, reusable and composable building blocks represented by components. Checking of architecture constraints is provided via service invocation through ports of a special kind of components, called constraint-components. The signatures of these checking services can be defined in required interfaces of business components, to document decisions taken while designing their architecture. They can also be part of other required interfaces of constraint components, making it possible to build higher-level or more complex constraints while reusing existing ones. We present an example of implementation of constraint components using, an ADL which is introduced in this paper. Architecture constraints can then be checked on the architecture of business components at design-time using the CLACS tool support, which has been implemented as an Eclipse plugin.