Research And Implement Of Distributed Workflow Engine

Business processes play important roles in enterprise's management, for there are various business processes in modern production and management activities. Among the functions WFMS should implements, modeling the business processes, supporting automation and continues improvement and passing various messages according to user defined business rules are most essential. The requirements to WFMS vary largely in different practical scenarios. Sometimes the ability of real-time response, accuracy and regularity are critical, while in other situations flexibility, stability, security considerations are much more important.The topic of flexibility, cooperation and integration in WFMS is still opening. In this article, we discuss the design of distributed workflow engine and technology of implementation based on practical experiences. Then we introduce a prototype system named D-FlowEngine.In the 1st chapter, we firstly introduce the origin, development and future of workflow management. Then we describe the status in quo and the opening problems in this area.In the 2nd chapter, we discuss several implement technologies in distributed computation such as CORBA, DCOM, Java RMI, J2EE, Web Service. Then on this basis, we propose a distributed architecture of WFMS. Finally we analyze several key points of it.In the 3rd chapter, a practical distributed workflow model that is composed of process model, data model, application model and supporting model was given. Then we propose an inherent hierarchy of it, which is critical to reusability and version management of workflow model and workflow instance execution flexibility.In the 4th chapter, based on technologies in quo, we proposed a data consistency-protecting framework that includes lock mechanism, data protecting model, multi-version management and process-level transaction failure model.In the 5th chapter, based on the distributed workflow model above, we proposed a solution to routing and evolvement schedule of process, which satisfy user's multi-level alteration requirement. Aiming at the problem in assigning executors of task, we propose a flexible role resolve model that can adapt smoothly to various environments.In the end, all of the works in this dissertation are summed up, and their futures are prospected.