We exploit the main similarity between the aspect-oriented programming paradigm and the inter-object, scenario-based approach to specification, in order to construct a new way of executing systems based on the latter. Specifically, we transform multimodal scenario-based specifications, given in the visual language of live sequence charts (LSC), into what we call scenario aspects , implemented in AspectJ. Unlike synthesis approaches, which attempt to take the inter-object scenarios and construct intra-object state-based per-object specifications or a single controller automaton, we follow the ideas behind the LSC play-out algorithm to coordinate the simultaneous monitoring and direct execution of the specified scenarios. Thus, the structure of the specification is reflected in the structure of the generated code; the high-level inter-object requirements and their structure are not lost in the translation. The transformation/compilation scheme is fully implemented in a UML2-compliant tool we term the S2A compiler (for Scenarios to Aspects), which provides full code generation of reactive behavior from inter-object multimodal scenarios. S2A supports advanced scenario-based programming features, such as multiple instances and exact and symbolic parameters. We demonstrate our work with an application whose inter-object behaviors are specified using LSCs. We discuss advantages and challenges of the compilation scheme in the context of the more general vision of scenario-based programming.

In this paper - as a natural extension of the idea of using visual formalisms for the modeling itself - we present a technique for the visualization and exploration of execution traces of such models. Our approach is different from previous approaches, most of which consider execution traces at the code level, look for interaction patterns in the traces, or generate concrete sequence diagrams from recorded execution traces. In contrast, we take an inter-object scenario-based behavioral model given by the designer as input, and visualize the activation and progress of the scenarios therein as they "come to life" during execution. We illustrate the ideas using modal scenarios, given in a UML-compliant dialect of live sequence charts (LSC).