Rules and Strategies in Java

ELAN was one of the first rule based language to introduce a clear separation between the notion of rule and the notion of control, also called strategy. Starting from this experience, our goal was to make available these constructs in a widely used language such as Java. In this paper we present the essential features we have considered when designing the Tom language, which is an extension of Java that integrates the notions of rules and strategies. Relying on the implementation, we explain how these ingredients can be implemented and smoothly integrated in a Java environment.