Principles of UML-based component modeling

With the proliferation of middleware technologies and component infrastructures, there is a growing need to support high-level, platform.independent ways of modeling components and component-based systems. This need is reflected in the model-driven architecture vision of the Object Management Group (OMG). However, component modeling involves much more than merely depicting physical deployment units using the Unified Modeling Language's (UML) component notation. On the contrary, since components are often large, highly complex subsystemsof an application, they can be fully described only using the full range of the UML's modeling portfolio. This chapter explains how this can be done. It suggests for basic principles by which the UML should be used to document components and component-based systems in a rigorous, engineering-based manner. These principles essentially clarify how the core principles of software ngineering (information hiding, separation of concerns, etc.) can be applied at the model level in terms of suites of interrelated UML diagrams.