Building Rich Internet Applications with J2EE, Open Source, and AJAX

AJAX Application: 

The unit of work becomes much more granular with AJAX. Instead of working with forms & pages, developers can work at the field level. Unlike page-based applications, individual fields can be submitted to the server at any time. This means that the server code receiving the client requests must also be more granular. In fact, to take full advantage of AJAX's ability to converse with the server requires that developers focus on components and events versus pages and actions. This is how development was done in client/server applications.

In addition, with AJAX applications, the server can return more than just an HTML page. It can return a single field or status message, multiple fields, XML, HTML, and even Javascript to be executed on the client---and all at the same time. Page elements communicate with back-end components.

AJAX applications, however, come with increased complexity.

When building AJAX-based applications, developers must:

- Code extensive Javascript functions & event handlers - Create complex HTML/DHTML pages - Build reusable DHTML components - Manually handle client-side layout - Implement data binding & unbinding mechanisms - Perform extensive browser DOM manipulation - Handle errors - Build server-side functions or servlets to process requests - Marshal & unmarshal XML requests & responses - Test across multiple browsers - Manage browser to server AJAX requests

Because of all the moving parts and the increase in granularity, building AJAX applications will be slow without tools and frameworks. Just as client/server development was successful because of focused environments such as PowerBuilder and Visual Basic, real AJAX development will be successful with similar productivity tools.

There are many approaches to AJAX development emerging. Some frameworks concentrate only on browser to server interaction; some concentrate on XML manipulation, some on graphics effects, and some on server-side AJAX support.

ThinkCAP Delivers AJAX Web Applications and 3-Tier Client/Server Development

At ClearNova, we believe that AJAX applications is ushering in a new way of building web techniques along with the power and usability that AJAX & DHTML provide and that users want.

The result is ThinkCAP JX, a highly visual 3-tier client/server web development environment with a sophisticated event model, integrated layout management for both client & server, data binding, transaction control, data persistence, advanced visual controls, and Eclipse integration all based on an open source foundation.

Interactive AJAX applications are event-driven. Developers must be able to write code that executes when a button is clicked, a field is changed, or when the user highlights an area. ThinkCAP completely changes how web applications are built by providing a practical 3-Tier client/server event model and allowing developers to choose whether code is executed on the client or the server or both.