基于服务协作中间件的动态流程模型

A Dynamic Process Model Based on Service Cooperation Middleware

新兴的面向服务体系结构正在加速软件的发展和变化,无法适应动态环境的应用将逐渐失去作用,尤其对那些面临着需求频繁变更的业务流程管理系统而言更是如此.为了响应这种现实需求,基于Web服务和业务流程管理技术,提出了服务协作中间件(service cooperation middleware,简称SCM)模型,探讨了其内部机理与协作流程元模型的形式化.通过引入模型转换,扩充流程状态空间,定义了动态流程模型,动态流程的结构重构和行为自适应可以借助SCM的反射能力得以实现.针对SCM模型,设计了流程虚拟机(process virtual machine,简称PVM),流程在运行时由PVM控制执行.借助于模型驱动机制,业务流程可从设计到运行不断地进行模型变换.由此建立的业务流程能够更灵活、更广泛地适用于各种开放环境,提升企业分布计算.

Emerging service oriented architecture is increasing the evolution and variation of software resources. Applications that cannot adapt to dynamic environments will decrease their usefulness, particularly to business process management systems that face requirements changed frequently. In response to the realistic requirements, this paper, based on Web services and business process management techniques, propose a model of service cooperation middleware (SCM) for enterprise computing. First, it discusses the conceptual architecture and operation mechanisms of SCM, then formalizes the meta-model of cooperative processes deployed on SCM. By introducing a model transformation function into the formalization, a static process model can be extended to a dynamic one. In virtue of the reflection capability, structural reconstruction and behavioral adaptation of the dynamic processes can be achieved in SCM by introspection and effectuation. In terms of the conceptual model of SCM, a process virtual machine (PVM) is designed as a running container for cooperative processes. Borrowed from the power of MDA mechanism, the model of a business process can be transformed successively from design to run time. The business processes established on SCM can be more flexibly and extensively applied to various open environments, and leverage modern enterprise computing.