Modeling and executing ConcurTaskTrees using a UML and SOIL-based metamodel

In this paper, we present a formal metamodel-based approach for modeling and executing ConcurTaskTrees (CTT). CTT is a modeling language for tasks that represent hierarchical tree-like, structured workflow models. In the metamodel soundness properties as well as operational semantics of the workflow language are captured. The models are created with an abstract syntax in the UML-based Specification Environment (USE). Thereafter, they can be executed in the same tool by calling operations from the metamodel that are implemented in the Simple OCL-based Imperative Language (SOIL). A plugin for the USE tool has been developed to give an appropriate interface to the user who can test dynamic control flow properties of the models with it.