Due to lack of strictly defined formal semantics, an UML activity diagram is unsuitable for the tasks of formal analysis, verification and assertion on the system it describes. In this paper, Petri net is used to defi...Due to lack of strictly defined formal semantics, an UML activity diagram is unsuitable for the tasks of formal analysis, verification and assertion on the system it describes. In this paper, Petri net is used to define the formal semantics of an UML activity diagram containing object flow states, laying a foundation for the precise description and analysis of a workflow system.展开更多
UML 2.0 activity diagrams (ADs) are largely used as a modeling language for flow-oriented behaviors in software and business processes. Unfortunately, their place/transition operational semantics is unable to capture ...UML 2.0 activity diagrams (ADs) are largely used as a modeling language for flow-oriented behaviors in software and business processes. Unfortunately, their place/transition operational semantics is unable to capture and preserve semantics of the newly defined high-level activities constructs such as Interruptible Activity Region. Particularly, basic Petri nets do not preserve the non-locality semantics and reactivity concept of ADs. This is mainly due to the absence of global synchronization mechanisms in basic Petri nets. Zero-safe nets are a high-level variant of Petri nets that ensure transitions global coordination thanks to a new kind of places, called zero places. Indeed, zero-safe nets naturally address Interruptible Activity Region that needs a special semantics, forcing the control flow by external events and defining a certain priority level of executions. Therefore, zero-safe nets are adopted in this work as semantic framework for UML 2.0 activity diagrams.展开更多
文摘Due to lack of strictly defined formal semantics, an UML activity diagram is unsuitable for the tasks of formal analysis, verification and assertion on the system it describes. In this paper, Petri net is used to define the formal semantics of an UML activity diagram containing object flow states, laying a foundation for the precise description and analysis of a workflow system.
文摘UML 2.0 activity diagrams (ADs) are largely used as a modeling language for flow-oriented behaviors in software and business processes. Unfortunately, their place/transition operational semantics is unable to capture and preserve semantics of the newly defined high-level activities constructs such as Interruptible Activity Region. Particularly, basic Petri nets do not preserve the non-locality semantics and reactivity concept of ADs. This is mainly due to the absence of global synchronization mechanisms in basic Petri nets. Zero-safe nets are a high-level variant of Petri nets that ensure transitions global coordination thanks to a new kind of places, called zero places. Indeed, zero-safe nets naturally address Interruptible Activity Region that needs a special semantics, forcing the control flow by external events and defining a certain priority level of executions. Therefore, zero-safe nets are adopted in this work as semantic framework for UML 2.0 activity diagrams.
