We present prominent features of AUTOFOCUS, a tool prototype for the formally based development of reactive systems. AUTOFOCUS supports system development offering integrated, comprehensive and mainly graphical description techniques to specify both different views and different levels of abstraction of the system. To avoid illdefined specifications, consistency conditions on these system descriptions can be formulated and checked. Furthermore, we show how consistent and executable specifications of systems or components can be animated using the Java code generation of the AUTOFOCUS simulator. Finally, we demonstrate how AUTOFOCUS can be used to simulate the specified system in its system environment using a graphic animation tool as an example.

In this paper we present a case study on Auto-Focus, a tool prototype for the development of distributed and concurrent systems based on the concepts of the formal method Focus. We develop (specify, consistency-check and simulate) the controller of a pedestrian traffic light using different graphical description techniques to illustrate an engineering process for concurrent systems.