Declarative Representation of UML State Machines for Querying and Simulation

Among the various aspects of the Unified Modeling Language, state machines are utilized to model the dynamic behavior of reactive systems. In this paper we present a platform where we transform a state machine into a declarative model, implemented as a database of clauses in Prolog. To tackle the complexity of composite states, we propose an algorithm for flattening the state machine’s representation. Both initial and flattened declarative models allow for querying on the quality attributes, the behavior and the well-formedness of the underlying machine. To complement the query-based analysis, we present a simulation process and we describe its automation and tool support. We demonstrate the analysis through a case study. The approach can assist software developers while performing validation of requirements.