In web application, Struts/JSF MVC framework are pretty popular. However, Ajax-based web application can make this process simpler. As the following figure shows, Ajax based application only need a simple servelet to transfer data. Compare with MVC framework, this is a small job. At the same time, a good Ajax Util framework will create rich GUI in the client browser with simple javascript/html code. In general Ajax can be separated as 3 parts:
First part is client-side Ajax, such as animation, drag-and-drop, rich editor etc. YUI, dojo, rico provide lots of great examples.
Second part is the bridge between browser side and Java server side, like bunch of RPC frameworks, DWR, prototype, YUI etc.
Third part is general Ajax Util framework (templates) which can be applied to most applications, such as search function, paging function, CRUD/List function etc. We can think them as glue tool between browser and server, and it will dramatically reduce code by using those utils. YUI extension provides great example for this.
