Mission modes for safety critical java

Abstract

Java is now considered as a language for the domain of safety critical applications. A restricted version of the Real-Time Specification for Java (RTSJ) is currently under development within the Java Specification Request (JSR) 302. The application model follows the Ravenscar Ada approach with a fixed number of threads during the mission phase. This static approach simplifies certification against safety critical standards such as DO-178B. In this paper we extend this restrictive model by mission modes. Mission modes are intended to cover different modes of a real-time application during runtime without a complete restart. Mission modes are still simpler to analyze with respect to WCET and schedulability than the full dynamic RTSJ model. Furthermore our approach to thread stopping during a mode change provides a clean coordination between the runtime system and the application threads. © IHP International Federation for Information Processing 2007.