Exceptions in Component Interaction Protocols - Necessity

At ADL level, most of the current interaction protocols designed to specify components’ behavior at their interfaces do not allow to capture exceptions explicitly. Based on our experience with real-life component based applications, handling exceptions as first class entities in a (formal) behavior specification is an absolute necessity. Otherwise, due to the need to capture exceptions indirectly, the specification becomes very complex, therefore hard to read and, consequently, errorprone. After analyzing potential approaches to introducing exceptions to LTS-based interaction specification (expressed via terms/expressions) in ADL, the paper presents the way we built exceptions into the behavior protocols. Finally, we discuss the positive experience with applying these exception-aware behavior protocols to a real-life Fractal component model application.