Vendors Hail Dom 2

New W3C spec for XML gives developers standard programming model.

Vendors planning to implement the new DOM standard, issued by the World Wide Web Consortium last month, are welcoming new capabilities for what has become a key driver of XML.

Document Object Model is used as a programming model within a browser as well as a primary interface for Extensible Markup Language. DOM Level 2, or DOM 2, is more powerful than the first iteration and provides developers with a standard programming model.

"It provides increased standardization of how people will manipulate XML documents in programs," said Bob Sutor, director of e-business standards strategies for IBM, in Somers, N.Y.

DOM 2 includes a standard API for manipulating data and documents through programming languages such as JavaScript. DOM 2 allows users to dynamically update a documents content, structure and style. The new standard adds support for namespaces, CSS (Cascading Style Sheets) 1 and 2, a standard model for combining objects, and a standard interface to manipulate those objects.

Key among the new features is the namespaces support, Sutor said. "It allows you to mix and match XML content from different sources," he said. "Namespaces is very important in using XML for publishing and for e-business."

The style sheets let users dynamically control the way a document is formatted and how it looks.

"The significance of Level 2 is there are some pieces of functionality we didnt have before because the base-level technology" wasnt there, said Lauren Wood, director of product technology for SoftQuad Software Inc., in Vancouver, British Columbia, and chairwoman of the W3C working group on DOM. Wood noted that DOM 1 has been widely adopted in tools and other products. "We expect the core level for DOM 2 to be as widely implemented," she said.

David Turner, Microsoft Corp.s product manager for XML technology, said Internet Explorer 5.5 already has support for pieces of DOM 2.

"We think its good stuff and [has] some useful functionality there," said Turner, in Redmond, Wash. "We have work under way to provide DOM Level 2 support in our products. I think [DOM] has, in fact, been one of the pieces that has enabled XML to grow as rapidly as it has. It gave implementers like us a design target."

However, Turner added that the standard is a little bit ahead of Web developers, and it will take time for the demand for DOM 2 to grow.

The working group has started on the third iteration of DOM. The W3Cs stamp on DOM 2 means the specification is stable for implementation and deployment.