一种实用的工作流异常处理机制

提出了一种基于虚拟组织集成框架IFVO的工作流管理系统的异常处理机制,深入分析了工作流系统异常处理的相关问题,并结合实例阐述了该机制的实现和应用。     

基于事务和Agent联邦的工作流异常处理机制

异常处理和恢复是工作流管理系统(workflow management system,WFMS)不可缺少的部分.在把工作流异常分为技能级异常、活动级异常和工作流级异常的基础上,结合工作流中活动的事务性,提出了基于事务的异常处理策略,并在基于Agent联邦中各Agent的合作性,提出了异常的检测方法和传递机制,提高了系统处理异常的灵活性.     

异常处理机制研究

介绍了异常处理机制,包括异常的抛出、捕获、传播,并描述了异常的处理模式、传播机制、处理环境。不同应用领域的异常处理机制不同,以Java语言和工作流管理系统为例,分别介绍和讨论了程序设计语言层面和企业层面上的异常处理机制。     

基于多Agent虚拟组织工作流管理系统的异常处理机制

异常处理和恢复是工作流管理系统不可缺少的部分，文章结合基于多Agent虚拟组织的工作流管理系统SalFlow，提供了一套异常发现，处理和传递的方法，并提出了面向广义资源的工作流事务模型，以支持数据的一致性控制以及工作流的撤消和恢复。     

基于多代理的工作流管理系统中的监测研究

基于多代理的工作流管理系统成为工作流应用中的一种重要的形式。作为实用的软件系统必须提供一种监测机制,以保证系统的健壮性、稳定性。该文在分析基于多代理的工作流管理系统的结构以及异常产生和异常之间的相互关系后,根据实际情况提出了一套监测策略,首先提出三层系统模型,把异常的检测和处理也相应地分成三层,然后通过在程序中增加异常触发机制和向后恢复的方法实现系统的健壮性,稳定性。     

工作流异常处理技术的研究

在工作流系统中,异常事件出现是不可避免的,如何处理工作流异常非常重要,本文先介绍了工作流异常的的基本概念,然后阐述了工作流异常的处理方法,提出了工作流异常处理机制设计和工作流异常处理规则的数据结构。     

基于访问控制模型的工作流任务指派异常处理

在电子政务、电子商务等工作流应用环境中,工作流任务指派异常主要由指派主体不可用导致,进行该类异常处理必须考虑访问控制系统的授权、约束、委托模型。结合访问控制相关知识,提出了通用的异常处理方法,通过引入相应的基本概念、异常事件及操作。给出了基于访问控制模型的工作流任务指派异常处理实现的ECA规则示例。该方法不仅可以降低工作流管理系统（WFMS）异常处理的复杂度,而且具有一定通用性,利于构建大型综合应用系统的统一异常处理机制。     

工作流管理系统异常处理的方法与层次

工作流技术在信息处理领域的应用越来越受到重视,但应用中环境和用户要求的不断发展和变化需要工作流管理系统具有灵活的处理能力,工作流系统的异常处理正是要解决这种不断要求的变化。文章介绍了工作流异常处理的应用范围,总结了不同的应用方法,从系统的角度提出了工作流未来的异常处理层次,并在研究可适应性工作流技术方面进行了探讨。     

工作流管理系统柔性机制

随着工作流管理系统在各个领域的应用,系统的柔性机制引起人们的极大关注。该文介绍柔性化工作流管理系统的基本概念及架构,描述从多个方面对工作流管理系统进行柔性化扩展的特点和实现机制。设计并实现一个具有更强适应能力的柔性工作流管理系统,实践证明该机制有效。该系统的实现也为异地的业务流程处理,甚至是跨平台间的业务组织和流程调用提供了良好的工作基础。     

基于CPN的工作流异常处理模型设计

工作流异常处理是工作流管理系统中的重要组成部分,但是它的实现既复杂又耗时。为了支持面向服务的工作流,层次化地描述异常处理,提出一种基于CPN的异常处理模型。在形式化描述工作流异常的基础上,采用补偿法作为异常处理方式,详细描述了处理结构中的异常监控、异常分析和补偿案例执行三个子过程。结合茶餐厅的运营模型的仿真实验证明了该模型可有效地分离工作流的异常处理逻辑和运行逻辑,并支持工作流管理系统的实施。     

A rule-based approach to proactive exception handling in business processes

Effectively handling exceptions in business process is an important capability of enterprises in the current global market environment, since their business processes are becoming more complex. Effective exception handling requires systematic support for the entire scope of exception handling: from exception prediction to exception prevention, and from exception detection to exception resolution. Most existing research approaches to exception handling in business process management and workflow areas have focused on reactive exception handling which resolves exceptions only after their occurrences. Therefore, a proactive exception handling approach is required to predict and prevent business process exceptions as early as possible before they occur, and detect and resolve exceptions as soon as possible after they occur. This paper presents comprehensive behavioral, functional, and informational requirements for proactive exception handling from the lifecycle perspective. Then, it proposes a rule language for proactive exception handling based on the requirements. The proposed rule language will enable effective and flexible exception handling by providing the information required for the entire scope of exception handling, especially, for exception prediction and prevention. Finally, the paper illustrates and validates the rule language with an example of exception prevention and a prototype system.     

流程违例处理的行为及分析

业务流程运行期间,外部或运行环境中的某些属性与流程设计时所设定的条件不一致时,将导致流程运行时的违例,违例处理方法涉及流程运行时违例的发现和处理。首先介绍了流程的违例及其分类;基于流程违例处理模式,使用CCS偶图对流程工作项级、案例级违例处理以及相关补偿处理进行分析和表述;在违例处理策略讨论的基础上,总结了违例处理模式的基本形式,并通过CCS偶图的动态特征分析了违例处理的动态行为。     

Context aware exception handling in business process execution language

ContextFault handling represents a very important aspect of business process functioning. However, fault handling has thus far been solved statically, requiring the definition of fault handlers and handling logic to be defined at design time, which requires a great deal of effort, is error-prone and relatively difficult to maintain and extend. It is sometimes even impossible to define all fault handlers at design time.ObjectiveTo address this issue, we describe a novel context-aware architecture for fault handling in executable business process, which enables dynamic fault handling during business process execution.MethodWe performed analysis of existing fault handling disadvantages of WS-BPEL. We designed the artifact which complements existing statically defined fault handling in such a way that faults can be defined dynamically during business process run-time. We evaluated the artifact with analysis of system performance and performed a comparison against a set of well known workflow exception handling patterns.ResultsWe designed an artifact, that comprises an Observer component, Exception Handler Bus, Exception Knowledge Base and Solution Repository. A system performance analysis shows a significantly decreased repair time with the use of context aware activities. We proved that the designed artifact extends the range of supported workflow exception handling patterns.ConclusionThe artifact presented in this research considerably improves static fault handling, as it enables the dynamic fault resolution of semantically similar faults with continuous enhancement of fault handling in run-time. It also results in broader support of workflow exception handling patterns.     

请求驱动的校务管理系统异常处理机制

异常处理机制是所有WEB应用设计中的关键组成部分,Spring MVC框架提供了异常处理接口和多种解析器. 通过源码分析法深入探讨了各种解析器的工作原理,总结得出它们的时间复杂度并进行了应用方式对照. 结合我校在校务管理系统基础框架上异常处理的应用需求情况,将异常划分为业务异常和系统异常两大类,设计并实施一个包含AJAX异常处理和ExceptionHandler统一异常处理的异常机制.     

Extended event–condition–action rules and fuzzy Petri nets based exception handling for workflow management

Exception handling plays a key role in dynamic workflow management that enables streamlined business processes. Handling application-specific exceptions is a knowledge-intensive process involving different decision-making strategies and a variety of knowledge, especially much fuzzy knowledge. Current efforts in workflow exception management are not adequate to support the knowledge-based exception handling. This paper proposes a hybrid exception handling approach based on two extended knowledge models, i.e., generalized fuzzy event–condition–action (GFECA) rule and typed fuzzy Petri net extended by process knowledge (TFPN-PK). The approach realizes integrated representation and reasoning of fuzzy and non-fuzzy knowledge as well as specific application domain knowledge and workflow process knowledge. In addition, it supports two handling strategies, i.e., direct decision and analysis-based decision, during exception management. The approach fills in the gaps in existing related researches, i.e., only providing the capability of direct exception handling and neglecting fuzzy knowledge. Based on TFPN-PK, a weighted fuzzy reasoning algorithm is designed to address the reasoning problem of uncertain goal propositions and known goal concepts by combining forward reasoning with backward reasoning and therefore to facilitate cause analysis and handling of workflow exceptions. A prototype system is developed to implement the proposed approach.     

基于补偿业务生成图的组合服务异常处理方法研究

为提高组合Web服务执行的一致性、可靠性,提出一种基于补偿业务生成图的组合服务异常处理方法.基于业务流程中任务间补偿依赖关系,讨论了补偿业务生成图的自动生成问题.重点讨论了补偿任务、补偿目标和服务转让应用模式,并相应地介绍了支持框架和相关技术.在此基础上设计了补偿依赖关系、补偿业务生成图的自动生成及组合服务执行过程中异常处理算法.当业务流程出现异常采取向前或向后恢复处理时,该方法在保证补偿实现的同时,兼顾补偿服务不存在或补偿服务代价过高的问题,提高了业务流程执行过程中的自动化水平和自适应能力.仿真结果证实,该方法保证了异常发生时组合服务执行的可靠性和一致性.     

浅谈C#程序中的异常处理机制

程序设计中,异常是一个不可忽略的元素,因此,有效的异常处理是程序完善的重要标志。重点介绍了C#语言中的异常处理机制。主要包括异常的基础知识、异常处理机制、程序设计中的异常三个部分。异常基础知识部分,讲解了什么是异常,异常发生的情况及主要的异常类,使读者对程序异常有基本的认识。异常处理机制部分,从应用程序和理论两方面对C#语言中对异常的处理机制进行讲解,详细分析了三种异常处理语句。程序设计中的异常部分,通过一个简单的程序开发中的例子扩展异常机制在程序设计中的应用,拓宽软件开发人员的设计思路。     

PL/SQL中的异常管理

在大型数据库应用程序的构建过程中,难免程序在运行时不会出错,然而,代码如何响应和处理这些错误往往决定着一个应用程序的成功与否.从异常类型、如何引发异常、如何自定义异常、如何处理异常4个方面来探究PL/SQL中的异常处理机制.     

基于轻量级Java EE框架的异常处理研究

正确使用异常处理机制对设计可靠、健壮的程序十分重要。对轻量级框架Struts2、Spring和Hibernate的异常处理进行分析,通过研究数据层、业务层、表现层的异常处理方式,结合异常抛出的种类以及在异常发生时的程序流程控制,提出了Java EE系统开发中,层与层之间异常的声明与处理方式,以及异常信息的包装再处理过程。     

Exception handling refactorings: Directed by goals and driven by bug fixing

Exception handling design can improve robustness, which is an important quality attribute of software. However, exception handling design remains one of the less understood and considered parts in software development. In addition, like most software design problems, even if developers are requested to design with exception handling beforehand, it is very difficult to get the right design at the first shot. Therefore, improving exception handling design after software is constructed is necessary. This paper applies refactoring to incrementally improve exception handling design. We first establish four exception handling goals to stage the refactoring actions. Next, we introduce exception handling smells that hinder the achievement of the goals and propose exception handling refactorings to eliminate the smells. We suggest exception handling refactoring is best driven by bug fixing because it provides measurable quality improvement results that explicitly reveal the benefits of refactoring. We conduct a case study with the proposed refactorings on a real world banking application and provide a cost-effectiveness analysis. The result shows that our approach can effectively improve exception handling design, enhance software robustness, and save maintenance cost. Our approach simplifies the process of applying big exception handling refactoring by dividing the process into clearly defined intermediate milestones that are easily exercised and verified. The approach can be applied in general software development and in legacy system maintenance.