Process And Implementation Of Workflow Exception Handling Based On Extended UML Activity Diagram

In these years, workflow developed fast, because company extended and market changed rapidly, the information that needed to handle was more and more, its task did not only realize business automatically, but also express the complex information and dual with kinds of conditions. Although there was a great dual of WFMS with handling exception, they were not express workflow in detail, only had the function of handling exception. Today's workflow needs descriptive and functionality, only in this way can it develop a new height.This thesis studies workflow models and chooses UML activity diagram and extends it from several aspects which workflows need have. From graphics, it adds some nodes about email and state and gives them the certain semantics. The UML activity diagram can describe the workflow flexibly and comprehensively.In the aspect of workflow exception which could be forecasted, after studying transaction, this paper adds the structural unit and functional unit. They restrict recovery range and set recovery point automatically. In the workflow exception, this paper proposes MPA rules which make trigger of exception and priority associated. In the aspect of workflow exception which could not be forecasted, this thesis runs T-workflow recovery strategy by consistency units. This method bases the principle of recovering the same layer and spreading and set recovery size to unit level. It also could improve workflow efficiency by reducing the execution of compensation task of every activity node by setting up the compensation tasks for different units.Finally, the paper realizes the exception of UML activity diagram in JBPM (Java Business Process Management) which doesn't have the function of handling exception.Mainly realize the extending of UML activity diagram in JPDL (Java Process Definition Language) and add some rules and realize recovery algorithm.