Tool-Supported Step-By-Step Debugging for the Object Constraint Language.

Although originally designed as an extension for the Uni ed Modeling Language (UML), the Object Constraint Language (OCL) has been broadly adopted in the context of UML as well as other modeling and domain-speci c languages. However, appropriate tooling, supporting software developers on using OCL is still scarce and lacks debugging support. As OCL constraints are likely to become rather complex for real world examples, it is typically hard to comprehend the in uence of single OCL expressions on the result of an evaluated OCL constraint. Therefore, debugging is of topmost importance for both constraint comprehension and maintenance. In this paper, we evaluate existing debugging tools for OCL and come to the conclusion that no real step-by-step debugger for OCL exist, yet. Therefore, we analyze requirements for OCL debuggers and present an OCL debugger implementation for Dresden OCL.