Extensible Markup Language (XML) in many ways augments Java; however, XML is also evolving into an object transport protocol that could undermine Java's claim as a does-all platform.
XML tags Web-based information for recognition by developers and computers, which is necessary because HTML lacks a way to add meaning to content aside from cryptic URLs. XML aims to add that meaning to Web objects -- a task once assigned to Java.
XML lets developers choose between building Web applications or Java systems, said Adam Berrey, US-based product marketing director at Allaire, a maker of Web application servers. All that is needed is a client that renders XML into HTML, not a Java virtual machine (JVM)-based client.
Sun acknowledges that XML can communicate to clients without JVMs, but it claims XML needs Java to reach its potential.
"XML is not useful alone; it is a complement to Java," said Nancy Lee, US-based product manger for XML at Sun Microsystems. "Java provides the portable code to [XML], and XML offers the data for Java."
At December's Java Business Expo, in New York, Sun will demonstrate a Java-based XML parser and APIs that use Java to provide core services to run XML in applications, according to Lee.
XML can create open data that is not dependent on a platform, language, or restrictive formatting convention. If widely adopted, XML could become a de facto standard for communicating content and objects down to clients.
That sounds a lot like what Java does, at least as a content platform. It is just such a role for XML that appeals to Microsoft, which disdains Java's use for purposes other than programming.
"XML lets you exchange information across platforms, not to be confused with writing cross-platform applications," said Dave Wascha, XML product manager at Microsoft in the US.