XMI Gets Boost from Rational, Unisys

No one ever said standards are adopted quickly. Most will agree, however, that standards are a useful tool in an ever-changing global enterprise. In order to make the lives of IT professionals, particularly developers, easier, standards are sometimes the only thing preventing a brand new learning curve every time a developer starts a new project.

Extensible Markup Language (XML) is the most exciting programming tool since Java, but even it goes through the molasses-like process of standards approval. One standard that's branched out from XML is the XML Metadata Interchange (XMI), designed to streamline collaborative application development efforts on the Web.

XMI was finally adopted by the Object Management Group (OMG, www.omg.org) in March 1999, but none of the participating vendors -- IBM Corp. (www.ibm.com), Unisys Corp. (www.unisys.com), Oracle Corp. (www.oracle.com), and Rational Software Corp. (www.rational.com) -- have done anything with it.

That was until last month when Rational announced it would be integrating XMI technology from Unisys into Rational Rose 2000, the company's widely-used visual modeling environment, as well as other Unified Modeling Language (UML) based tools and environments. The software is available as an addition, which can be downloaded from the Rational Web site.

XMI is intended to give developers working with object technology and using a diverse set of tools, even ones from different vendors, the ability to exchange programming data over the Internet in a standard method. For example, if a team of people have designed and created the architecture of the application, they can send the object to the programmers who can then make changes or additions using different software.

Now, with tools that understand XMI, UML, and the Meta Object Facility (MOF), developers can design an object in IBM's VisualAge for Java, tweak it in Rational Rose, and then work with it once again in Oracle Designer, all without losing a single line of data. As a result, development teams spread across the globe using various tools from multiple vendors can still collaborate on applications.

"This is about the maturation of XMI from becoming an early specification to a more mature representation," says Sridhar Iyengar, Unisys chief architect of metadata services. "Since Rational is the most significant UML vendor, this puts their stamp of approval on this interoperability."

Before this announcement, the technology was available but much more difficult to take advantage. You had to be both a Unisys and Rational customer, modeling the application in Rose, while using the Unisys repository to store objects.

What's also attractive about XMI is its ability to interact with the wide selections of development languages. In the case of a company such as Microsoft, who regularly adds proprietary extensions to interoperable standards, XMI anticipates vendors will customize their applications. Where tools are using custom extensions, and objects are sent from tool to another, XMI has the ability to transfer the proprietary objects through a special attachment mechanism.

"We are seeing this as a mechanism to use whatever too they want," explains Iyengar. "In either case, the model and the designs you have can be reused in COM-based development and even in Java-based development. XMI and UML are independent of any middleware."