The Design and Implementation of Real-time Event-based Applications with RTSJ

This paper presents a framework to design real-time event-based applications using Java. The real-time specification/or Java (RTSJ) is well designed for hard periodic real-time systems. Though it also proposes classes to model asynchronous events and deal with sporadic or aperiodic tasks, it remains insufficient. The literature proposes the use of periodic servers called task servers to handle non-periodic traffics in real-time systems. Unfortunately, there is no support for task servers in RTSJ. In order to fix this lack, we propose an RTSJ extension model. To validate our design, we adapt and implement two policies: the polling server and the deferrable server policies. To show how efficient these policies are, we compare implementation results and results obtained with a discrete-event-based simulator.