基于迁移策略的动态工作流的研究与设计

为了使工作流系统能够在运行过程中支持过程定义的动态可变,探讨工作流在过程方面发生动态修改的分类,分析重启、继续执行、迁移等多种动态修改策略的优缺点,重点研究了迁移策略的实现,提出了一种基于迁移策略的动态工作流的设计方法。该方法首先加载数据表中的过程定义信息,并根据反射机制动态创建相应的工作流对象及其方法。然后设计了一种迁移策略执行算法,根据迁移规则XML配置文件,动态完成运行时的旧工作流到新工作流的转换,从而提高了工作流系统的动态性。

Research and design of dynamic workflow engine based on migration strategy

In order to make the workflow system to support the dynamic variable of procedure definition in operation pro-cess,the classification of workflow which may occur the dynamic modification in the process is discussed. The advantages anddisadvantages of dynamic modification strategies,including restart,continuous execution and migration are analyzed. The imple-mentation of migration strategy is researched emphatically. A design method of dynamic workflow based on migration strategy isproposed. The information of process definition in the data table is loaded,and the appropriate workflow objects and theirmethods according to the reflection mechanism are dynamically created in this method. An executing algorithm of migration strate-gy is also designed. According to the migration rules which are written by XML,the workflow system accomplishes the conver-sion from the old workflow to the new workflow to improve the dynamic property of the workflow system.