Quality Assurance for Behavioral UML and OCL Models using Filmstripping

Abstract

In Model-Driven Engineering (MDE), models are used as an abstraction of a system. The Unified Modeling Language (UML) along with Object Constraint Language (OCL) is used to describe for a system the structural aspects, e.g., in terms of invariants, and the behavioral aspects, e.g., in terms of pre- and postconditions. As the size and complexity of models grow, there is an increasing need for testing their correctness. Therefore, a developer-friendly and efficient testing technique is essential that concentrates not only on the structural properties but also on the behavioral properties of the model. This thesis deals with enhancing and optimizing the behavioral testing technique available in the tool USE (UML-based Specification Environment). It allows the modeler to validate models and to verify properties by building test scenarios. In this thesis, we propose a new method for developing comprehensive OCL postconditions of an operation in UML and OCL models, including so-called frame conditions. Frame conditions define the elements which remain unchanged during the transition from one system state to another and are essential for model validation and verification methods. The method is realized by a transformation chain from an initial user-developed model into a semi-automatically derived test case model for checking the model quality. Configurations and additional OCL invariants are essential to construct a test scenario for model validation. In this thesis, we extend our tool USE by providing an option that automatically generates the configurations needed for the model behavioral testing. Furthermore, an approach is proposed to automatically transform a diagrammatic test case schema into a corresponding OCL invariant, reducing the overhead of a developer of writing it manually. The schema is a visual representation of a behavioral test scenario constructed by the developer. We also introduce a catalogue of different patterns to help the developer in constructing different dynamic scenarios for model testing.