基于ECA规则的GIS服务链异常恢复策略  

Exception recovery strategy for GIS service chain based on ECA rules

作　　者：易雄鹰[1] 任应超[1] 伍胜[2] 董鹏[3] 

机构地区：[1]中国科学院遥感与数字地球研究所遥感科学国家重点实验室,北京100101 [2]西南大学计算机与信息科学学院,重庆400715 [3]中国科学院遥感与数字地球研究所,北京100101

出　　处：《计算机工程与设计》2016年第2期396-400,共5页Computer Engineering and Design

基　　金：国家863高技术研究发展计划基金项目(2012AA12A401);中央高校基本业务费专项基金项目(XDJK2014C144)

摘　　要：为降低因GIS服务链异常导致的人工重规划机率,提高GIS服务链的鲁棒性,提出一种基于ECA规则的GIS服务链异常恢复策略。以保证GIS服务链事务正确性和完整性为目标,分析服务组合及工作流异常处理的常见策略,设计GIS服务链异常处理的基本模式和组合模式,分别对应简单场景和复杂场景的异常处理。利用ECA规则要素与异常处理元素映射关系,对BPEL语法进行扩充,以BPEL代码形式实现上述几种异常处理模式。结合实例,展示了该策略的实现效果,验证了采用该策略的GIS服务链具有更好的容错性。To decrease the chances of manual re-planning for geographic information system（GIS）service chain caused by exception,and improve its robust performance,an exception recovery strategy for GIS service chain based on event-condition-action（ECA）rules was presented.For the correctness and integrality of GIS service chain,popular exception handling strategies for service composition and workflow were analyzed,basic patterns and composite pattern were designed,corresponding to simple exception handling and complex exception handling respectively.By utilizing the mapping relationship between ECA elements and business process execution language（BPEL）,the basic exception handling syntax of BPEL was extended.Based on these,the patterns designed above were implemented in BPEL code form.A case study was presented to demonstrate the effects and better fault tolerance capability of GIS service chain.

关 键 词：异常处理 恢复 服务链 业务流程执行语言 事务 

分 类 号：TP399[自动化与计算机技术—计算机应用技术]