An Approach To Web Service Evolution Based On AOP

Web service technology can integrate various coupled applications loosely and makes the different operating systems, programming languages, and different application platform accessibility to connect and interoperability.Web service can be expanded,which makes it need to change itself constantly in the process of running to adapt to changes in service in various environments. The evolution of the service is an adaptive behavior of self-regulation for service itself in order to adapt to the changing environment. In order to adapt to the new demands, it has to change some of the properties. The changes may be change of service requirements, change of service strategy, change of service semantic or change of the service invocation and so on.With the continuous development and improvement of cloud technology, more and more enterprises will gradually transferred ordinary desktop application to the Internet as the media platform. Web service, as one of the best distributed computing model, becomes the mainstream framework to solve the problem of many development. In the face of rapidly changing Internet environment, the evolution of the Web service is a big challenge. In the SOA framework, in order to guarantee the normal operation of the services and continuously updated service requirements, solving the evolution of the Web service is an important goal.The evolution of the Web service led to a series of the changes and effects. In order to adapt to changes in these services, in the interaction mode of client and the server, for a perfect service system, the evolution of some services would be disastrous for changes to the system. The development and deployment of the service will take a lot of time and resources, while the deployment of new service may lead to conflict with the original service,thus reducing the service experience. At the same time, due to different client demand,which provides a different functional requirement of the service either. The traditional server unified demand can only make unified plans for most of the cases,resulting in unsafe factors to the customer’s privacy indirectly.So we need such a service mechanism, which can greatly save development cost and reduce workload in the face ofdevelopers, without taking resources and time for traditional service of the secondary development. And it can facilitate the maintenance of the later. Service evolved will not conflict with the joining of the new service. We can design different services according to different client demand. In the case of server uniform, the client needs to implement the on-demand service.In view of kinds of problems and needs put forward above, this paper puts forward a method of Web services evolution based on AOP technology. We establish an aspect library based on AspectJ in the background of the Web service evolution. It defines logical function in abstract aspect and the instance has specified points position as logical structure of aspect library. In defining join point location method it weaves in aspects in supporting Java Annotation, at the same time it supports functional module in the form of aspects woven into the service invocation;On the basis of the Axis2 service framework,it makes service in the process of running change. This way achieves the evolution of the service function without changing the service side, and it supports different clients a custom function in a certain range.