In: ACM SIGAda Ada Letters , Proceedings of the 1999 annual ACM SIGAda international conference on Ada, Volume XIX Issue 3, pages 211-220. ACM Press, September 1999.
Abstract: One important role for Ada programming is to aid engineering of concurrent and distributed software. In a concurrent and distributed environment, objects may execute concurrently and need to be synchronized to serve a common goal. Three basic methods by which objects in a concurrent environment can be constructed and synchronized have been identified [1]. To formalize the semantics of these methods and to provide a formal model of their core behavior, we provide some graphic models based on the Petri net formalism. The purpose of this formal modeling is to illustrate the possibility of automatic program analysis for object-oriented features in Ada-95. Models for the three distributed- object synchronization methods are discussed, and a potential deadlock situation for one of the methods/models is illustrated. We conclude with some comparison of the three methods in terms of the model abstractions.
Keywords: Ada-95; Petri net formalism; concurrent objects; distributed software; synchronization methods.