ConExT-U: A Context-Aware Exception Handling Mechanism for Task-Based Ubiquitous Systems

Abstract

Context-awareness is a central aspect in the design of ubiquitous systems, characterizing their ability to observe the environments context changes and adapt its structure and behavior according. Since those systems can be able to make autonomous decisions (i.e., without direct user intervention), dependability becomes an important requirement. The exception handling is a well-known error recovery technique employed to improve the software robustness and contributes to the overall software systems reliability and dependability. However, despite its benefits, exception handling still not widely used in the development of ubiquitous systems. In fact, we argue that is consequence of the lack of a proper exception handling mechanism to support it during the development and execution phases. In order to address this problem, we propose a contextaware exception handling mechanism designed specifically for context-aware ubiquitous systems. The proposed mechanism is implemented as a Java-based framework that provides a taskbased model for building robust ubiquitous systems. A prototype of a ubiquitous parking control system is implemented to explore and validate the features of the proposed mechanism.

CatchML - A Language for Modeling and Verification of Context-Aware Exception Handling Behaviour

“…The aforementioned abstractions provide a standard way to represent behavioral aspects regarding: the definition and detection of exceptional context; the grouping, selection and implementation of handling measures; and the resumption of the control flow. Furthermore, they have also been cited in other research studies [Damasceno et al 2006, Kulkarni and Tripathi 2010, Filho et al 2014] that address context-aware exception handling. We leverage the CAEHV method to provide a high-level solution for modeling and verification context-aware exception handling.…”