Research And Application Of Ajax Frameworks In J2EE Structure

With the emergence and development of Web2.0, more and more people are concerned with Ajax (Asynchronous JavaScript And XML).Ajax technology introduces a mechanism for asynchronous response, it can refresh partial pages and upgrade the user experience. Contrasting with Applet, Flash and other traditional Web technology, Ajax can be used directly and sends asynchronous requests through the XMLHttpRequest object in the most browsers without requiring specialized software support. Therefore, Ajax technology improves availability of the application through the elimination of excessive Web pages refreshing.However, during the use of Ajax technology, developers need to build XMLHttpRequest object and realize callback functions. If all such details needed to be realized on every element of web pages, there would be a lot of work to do and it is not easy for code management. At the same time, programmers are required to be very familiar with web technologies such as JavaScript, DOM, XML and others to control the effect of applying Ajax well. In the process of interaction with the server, there are certain flaws in data transmission security and logical processing on the backend. It seems that these have confirmed that the bottom technology of Ajax is still at an initial stage, and can not be widely used.With the rapid development of Ajax technology, the emergence of Ajax frameworks make the development of Ajax applied in Web application more rational, rapid and more powerful. Ajax frameworks solve the defects of Ajax. This paper uses the application of Ajax frameworks in J2EE development model to provide browsers with abundant reusable browser-interface components not only more the rich and powerful expression, but also more security, more agile and more reasonable with the server-side interactive data. Developing at an amazing speed, Ajax framework is endless field of new technologies, and plays a major role in web application development and the broad application of Web2.0.On the basis of researching on the field of Ajax frameworks, the paper chooses the popular Ajax frameworks ExtJS and DWR to do more research. Paper summarizes the specific application process and fundamentals of application in addition with their advantages compared with the traditional UI development and solution on rectifying the application of Ajax technology. On the server-side, this paper introduces the applicable process and fundamental of DWR and does some research on DWR relevant issues and concerned about security. The core of this paper is the integrated design method of Ajax frameworks and their specified realization. The integrated method is innovatively used to solve the traditional code issue of Ajax technology. Based on this method, an information system is designed and realized to put forward the realization of asynchronous requests of UI-control separation as the innovation of this instance application.