Model based functional testing using pattern directed filmstrips

Model driven functional system testing generates test scenarios from behavioural and structural models. In order to autmatically generate tests, conditions such as invariants and pre-/post-conditions must be precisely defined. UML provides the Object Constraint Language (OCL) for this purpose; however OCL expressions can become very complex. This paper describes an approach that allows many commonly found OCL patterns to be expressed as snapshot patterns that correspond directly to the information model diagrams. Behaviour is constructed as chains of snapshots, or filmstrips. Snapshots and filmstrips are as expressive as UML behaviour models and OCL but it is argued that they are more accessible and more modular.