【作者】 李志杰；

【导师】 熊前兴；

【作者基本信息】 武汉理工大学 ， 计算机应用技术， 2008， 硕士

【摘要】 随着Web服务应用的不断扩展,网上提供服务的数量越来越多,但有研究报告指出,提供的Web服务中,只有大约34%可用,每周大约有16%的已注册的Web服务失效,并且在可用的服务中服务的质量参差不齐。原来具有较高服务质量的服务,也可能由于条件的变化,服务质量急剧下降。因此面临两个问题:一是用户希望找到的服务不仅功能上满足要求,同时应该具有较高的服务质量。二是服务提供者所声称的服务质量可能由于条件的变化已经不复存在或有所下降,要能够从用户的角度对服务质量做出实时的评测。另外,目前的Web服务执行方式还是人工的,服务消费者必须事先人为地了解服务的技术细节才能调用服务。这种方式不管是对专业人员还是普通用户都造成了很大的麻烦,使得对Web服务的测试实施复杂,耗时费力,从而阻碍了Web服务应用的普及。针对上述问题,本文对Web服务自动执行问题、基于服务质量的服务发现问题、服务质量指标值量化及综合评价问题进行了深入的研究。论文建立私有UDDI注册中心用于存储服务注册信息;采用分类tModel的方法描述服务质量信息并存储在注册表中,很好的解决了Web服务质量的描述问题;采用“量化”的方法把服务质量指标值不同的描述形式统一成UDDI规范中的离散值;运用WSDL4J技术对WSDL文档进行解析,Axis提供的API对服务进行调用实现了Web服务的自动执行,方便了对Web服务服务质量的测试,提高了测试的效率。论文所设计和实现的Web服务搜索系统对服务质量相关的指标值进行了实时的测量,可以用于对服务质量进行实时的评价,从而使服务消费者能及时的了解服务质量的变化情况。本文设计和实现的Web服务搜索系统能够基于服务质量进行服务搜索,实现了Web服务的自动执行,能够对Web服务的服务质量进行实时的评测,具有一定的实际价值。更多还原

【Abstract】 As the application of Web services ceaselessly expand, more and more services were provided on the Internet, but a study report pointed out that only about 34 percent of them is available, 16 percent of the registered Web services fails weekly and the quality of available services is very different. The high quality of service may decline sharply due to changes in conditions. So web services face two problems: First, the user wants to find services that not only meet functional requirements but also with high quality. Second, because of changes of environment, the quality claimed by service provider has been declined or disappeared, so it is necessary to evaluate the quality of service timely from the user’s side. In addition, the current implementation of Web services is still artificial, service consumers must first artificially understand the technical details of services, and then can invoke services. This way has caused a lot of trouble to both technical users and ordinary users. It makes the implementation of Web services testing complex, time-consuming, thereby impedes the popularization of Web services application.Aiming at these problems, this thesis focuses on these aspects of Web services: automatic execution of Web services, discovery on condition of service quality, value quantization of service quality indexes and comprehensive evaluation. This thesis builds private UDDI registration center to store the registration information of Web services, uses classification tModel to describe information of service quality which was stored in registration center. This way can solve the problem of describing information of quality of service well. The description forms of service quality indexes are different from the discrete values in UDDI specification. The thesis use "quantitative" approach to resolve this contradiction. WSDL4J was used to resolve wsdl document, API provided by Axis was used to call services. They make web services can be executed automatically because of which the test of service quality becomes easy and efficient. Web services searching system designed and implemented in this thesis measures service quality indexes timely, can be used for real-time evaluation of service quality. Service consumers can timely know changes of service quality by help of the system.Web services searching system designed and implemented in this thesis can search web services on condition of quality of service, realize the automatic execution of web services, can evaluate quality of service timely. Thus has some practical significance.更多还原