摘要： 互联网上存在丰富的Web服务以及自动服务组合方法，但这些自动组合方法(如经典的Roman模型)均要求服务暴露其行为，以此作为服务是否可自动合成的先决条件。现有的Web服务描述文档(如W3C的WSDL标准)缺乏对服务行为的有效描述，使得这些自动化服务组合方法在实际中不可行。针对该问题，提出一种在WSDL中扩展服务行为描述的服务接口方案，基于GMF实现服务行为编辑器，帮助用户在WSDL中协同添加或编辑服务行为，并利用Axis2开源框架开发客户端生成器，根据WSDL中的服务行为反向自动生成具有服务行为的客户端。以k-lookahead算法为例在Seekda服务库中应用该服务方案，实验结果验证了其可行性。

关键词: WSDL扩展, 服务组合, Roman模型, k-lookahead算法, 服务客户端, 行为编辑器

Abstract: There exist abundant services on the Internet and numerous automatic composition methods. Composing these services by such automatic methods in the light of SOA certainly servers the next generation software development. However, almost such methods (including those elegant methods rooted in so-called Roman model) heavily rely on the provision of service behaviors, which is definitely deficient in practice as well as in standard(e.g. WSDL from W3C). To fill this gap, this paper develops a mechanism and an interaction protocol to bridge automatic composition methods with services in real world. This paper constructs a collaborative graphical tool to leverage Web Services Description Language(WSDL) files with service behavior annotations, and a client generator based on Axis2 to make generated client behavior-aware. It tests the approach with k-lookahead algorithm against some popular service repositories including Seekda. The results are very promising.

Key words: WSDL extension, service composition, Roman model, k-lookahead algorithm, service client, behavior editor

中图分类号: 

• TP393.07