Formalization in Component Based Development

We present a unifying conceptual framework for components, component interfaces,contracts and composition of components by focusing on the collection of properties or qualities that they must share. A specific property, such as signature, functionality behaviour or timing is an aspect. Each aspect may be specified in a formal languageconvenient for its purpose and, in principle, unrelated to languages for other aspects.Each aspect forms its own semantic domain, although a semantic domain may be parameterized by values derived from other aspects. The proposed conceptual framework is introduced by small examples, using UML as concrete syntax for various aspects, and is illustrated by one larger case study based on an industrial prototype of a complex component based system.