Combining Sequence Diagrams and OCL for Liveness

Formalizing Liveness-Enriched Sequence Diagrams Using ASMs

“…To address the important dichotomy between must and may we have shown in [4] how to achieve necessity, both at the global and the local level, using an extension of OCL for liveness. The idea is that by default a sequence diagram only reflects possible behaviour (except for the assert operator) or possible but forbidden behaviour (given by the neg operator).…”

“…Further, though they have been influenced by LSCs, they can still not adequately distinguish between must and may elements, necessary and possible behaviour. In a companion paper [4], we have addressed the dichotomy of necessary and possible elements and behaviour by simply enriching a sequence diagram with constraints for liveness. The constraints are given in a simple temporal extension of UML's constraint language OCL 2.0 [10].…”

“…The constraints are given in a simple temporal extension of UML's constraint language OCL 2.0 [10]. The extension consists of a liveness template after eventually (essentially as introduced in [2] but more expressive in [4]). This template can be used at the local level of a message or a lifeline, and at the global level of an interaction.…”

“…Nonetheless, fundamental liveness properties can still not be expressed in the new sequence diagrams. In recent work [4], we have proposed to solve this by enriching sequence diagrams with a simple but powerful Object Constraint Language (OCL) template for liveness. This template extends the one given in [2].…”

Relating computer systems to sequence diagrams: the impact of underspecification and inherent nondeterminism

“…In [CF04,CF05], Cavarra and Küster-FIlipe present an operational semantics for UML 2.x sequence diagrams inspired by LSC. Liveness properties are expressed by adding OCL (Object Constraint Language [OMG06]) constraints to the sequence diagrams.…”