Pattern-Based Translation of BPMN Process Models to BPEL Web Services

The business process modeling notation (BPMN) is a graph-oriented language primarily targeted at domain analysts and supported by many modeling tools. The business process execution language for Web services (BPEL) on the other hand is a mainly block-structured language targeted at software developers and supported by several execution platforms. Translating BPMN models into BPEL code is a necessary step towards standards-based business process development environments. This translation is challenging since BPMN and BPEL represent two fundamentally different classes of languages. Existing BPMN-to-BPEL translations rely on the identification of block-structured patterns in BPMN models that are mapped onto structured BPEL constructs. This article advances the state of the art in BPMN-to-BPEL translation by defining methods for identifying not only perfectly block-structured fragments in BPMN models, but quasi-structured fragments that can be turned into perfectly structured ones and flow-based acyclic fragments that can be mapped onto a combination of structured constructs and control links. Beyond its direct relevance in the context of BPMN and BPEL, this article addresses issues that arise generally when translating between graph-oriented and block-structured flow definition languages.