

Whereas most JavaScript frameworks focus on simplifying DOM access, it could be argued that Dojo is a one-stop solution. There currently are quite a few open source and commercial JavaScript frameworks available, including Prototype, EXTJS, YUI, and jQuery. You'll also learn about Dojo's support for object-oriented programming in JavaScript (which is based on familiar concepts such as classes, constructors, and inheritance), and get a quick introduction to Dojo modules. This article introduces you to Dojo's core features and widget library walks you through installing and setting up a JavaScript development and debugging environment (using Dojo and Firebug) and gets you started with building a sample application using Dojo. One of the more capable entries in this space is the Dojo toolkit, an open source JavaScript framework that you can use to create free or commercial applications. You can either write and maintain this infrastructure code on your own or take the less painful route of using a JavaScript library. Document object model (DOM) manipulation and event-handling logic that works across multiple browsers.Making asynchronous requests to the server side.

We commonly use JavaScript code for tasks such as: Web 2.0 has ushered in a very different programming model, where much of the application flow and business logic is developed using JavaScript on the client side. Accordingly, most Web 1.0 applications used some kind of Model-View-Controller (MVC) framework - such as Struts, JavaServer Faces (JSF), or Spring MVC - on the server side, but few needed a JavaScript framework for client-side programming.

Web application developers typically used JavaScript only for input validation and to display error messages to users. In the Web 1.0 world, the common Java application architecture called for implementing business and application flow logic with Java EE on the server side. In this first half of his introduction to Dojo, Sunil Patil introduces the toolkit's basic features, helps you set up your development and debugging environment, and shows you how to put Dojo's mojo to work in your Ajax development projects.

The open source Dojo toolkit distinguishes itself from other JavaScript libraries with capabilities that go far beyond simplifying DOM access. ReWeb 2.0 has brought with it the need to develop extensive JavaScript infrastructure code on the client side, something few Java developers saw themselves doing five years ago.
