Classifying and Modeling Exceptions through Object Process Methodology

Yudit Somekh, Dov Dori, and Mor Peleg

International Conference on Systems Engineering and Modeling-ICSEM'07, Haifa, Israel, March 20-23, 2007.


Exception handling is a fundamental issue that needs to be addressed by complex, safety-critical systems, such as embedded, real time, and medical decision-support systems. Modeling exceptions appropriately is a crucial step in a system design process, since correcting errors detected after the design phase can be very costly. Object Process Methodology (OPM) is a methodology that uses a single graphical model for describing systems, including their timing exceptions, and has been shown to be an effective modeling methodology. We have developed taxonomy of exceptions, and refined and extended OPM for eliciting, detecting, and handling different types of exceptions. Exceptions design patterns have been developed and a guideline-based methodology for utilizing and customizing these patterns in a system model is proposed. Using an industry-based cellular phone case study, we demonstrate the value of our approach in eliciting and modeling exceptions in complex reactive systems.