In previous columns, we described how Model-Driven Architecture (MDA™), a set of modeling standards from the Object Management Group (OMG), has evolved over the last few years. We discussed, and gave examples, about how MDA is now being used to support a wide variety of applications, including business process modeling, enterprise architecture, tool integration, testing, software lifecycle management, and systems integration, just to name a few.

Prior to MDA, tooling for most of these kinds of applications was largely proprietary, forcing users to deal with vendor lock-in, which made tool integration, migration and training difficult. By providing standards in this area, MDA made it much easier for development tools to interoperate, or at least exchange data. However, this still left each vendor with the unenviable—and uneconomical—task of building its own MDA platform, implementing all the relevant standards, and then maintaining and supporting that infrastructure over time. All this tended to slow down commercial adoption of MDA.

Going Open Source

Beginning in 2001 and led by IBM, the software development tools industry had already begun to move in a new direction: open source. IBM had quietly been building its own proprietary tooling platform, called Eclipse, for a number of years. IBM’s goal was to move all of its advanced development tools to a single platform, both to reduce overall tool development and maintenance costs, and to allow different IBM tools to exchange common information. This was similar to the strategy used by Microsoft to develop its very successful Visual Studio product line.

However, while developing Eclipse, IBM reanalyzed its business case and came to a startling conclusion: it could meet these goals much better if it placed the backbone technology of Eclipse into the emerging open-source community. On the one hand, moving Eclipse to open source would relieve IBM even further of the costs of extending, maintaining, and supporting the core Eclipse platform over time. On the other hand, compared to any proprietary initiative, an open-source Eclipse had the potential to create a much wider community much faster. This community would then be a natural market for IBM’s more advanced offerings.

The earlier success of open-source Linux had paved the way. With Linux, IBM realized it could readily afford to “give away” core software, because in the end, the company made much more money on its hardware, services, and higher-end software. Ultimately, the decision to move Eclipse to open source was just a logical result of applying that same insight to the software development tools business.

Needless to say, IBM’s gamble on open-source Eclipse has paid off handsomely. Many other major software tool vendors have followed IBM into the Eclipse community, along with a host of smaller vendors. Meanwhile, like most other open-source communities, the Eclipse user base has been growing by leaps and bounds. These users are typically first attracted by the availability of free development tools, and then by the sheer number and variety of Eclipse-based products—proprietary and open-source—that are now available.

EMF and MDA

As a very interesting side effect, the Eclipse phenomenon has also been a huge shot in the arm for MDA. The Eclipse Modeling Framework (EMF), arguably the most popular project within the Eclipse community, has largely adopted the MDA approach and implements most of MDA’s core specifications. These include the Meta Object Facility (MOF); Unified Modeling Language (UML); Query, View, Transformation (QVT); Object Constraint Language (OCL); MOF to Text (MOF2Text); and XML Metadata Interchange (XMI). In addition, EMF and related Eclipse projects also provide developers with a clear way to integrate MDA specifications with other popular development standards, such as HTML, CSS, JavaScript, XML, XSD, XSLT, SVG, SOAP, WSDL, and UDDI. (See Fig. 1.)

Through EMF, members of the larger Eclipse community are now being progressively exposed to the MDA approach, many for the first time. In short, the deeper users get into Eclipse and EMF, the more they learn about MDA. As they come to understand some of the basic features of MDA, they become more curious about the more advanced ones. They can then begin to explore those features in open-source EMF add-ons and EMF-hosted proprietary products. This is starting to expand the market for MDA-related training and consulting as well.

Not surprisingly, the rousing success of EMF has radically affected the strategy of many MDA vendors. When EMF was first introduced, some of the original MDA vendors felt threatened, viewing EMF as competition. In the end, however, many of these vendors decided that it was much better to migrate to EMF, rather than try to compete with it. They have now rehosted their proprietary products over the EMF platform.

Today, the list of leading vendors hosting their proprietary MDA-based modeling tools on EMF includes Borland, Compuware, SAP, Oracle, and, of course, IBM. At the same time, Eclipse and EMF have also become the hosts for products from open-source MDA vendors, such as AndroMDA.

Perhaps even more interesting are some of the new MDA open-source projects coming from large corporate users. Examples include SmartQVT from French Telecomm and TopCaseD from Siemens and Airbus. These are proof positive that, through Eclipse and EMF, MDA has already seriously penetrated the end-user marketplace.

All of these MDA players are now happily taking advantage of Eclipse’s wealth of platform features without having to pay anything for their further development, maintenance, evolution, or support, except perhaps in the form of their voluntary contributions to the community. They can now place the resources they’ve saved into more advanced features that add yet more value for their end users.

Meanwhile, those MDA vendors are gaining increased visibility for their products through the fast-growing Eclipse community. In the counter-intuitive economic logic of open source, both proprietary and open-source MDA tools proliferate as the Eclipse platform and community keep growing.

Is MDA Really Going Mainstream?

As yet another side effect, the OMG’s MDA standards-setting process is now also benefiting substantially from MDA’s ties to EMF. In the past, the time between the development of a new or enhanced MDA standard and its commercialization in proprietary software development tools and resulting end-user products could be as much as several years.

This caused many vendors and end users to wonder if MDA would ever really catch on in the broader marketplace, and how much effort was worth putting into developing and implementing MDA standards.

Now product features based on new and updated MDA standards need only be implemented and distributed within the EMF community to get wide attention. If accepted, they can then be rapidly integrated into hundreds of software development tools and thousands of end-user applications. With the large and growing community of active EMF users eagerly awaiting every new feature, new implementations of MDA standards soon get a thorough real-life workout in the global market.

This is also starting to have a positive impact on the overall market awareness of MDA. Just a year or two ago, some industry analysts were saying that MDA didn’t seem to be getting any commercial traction, and they were suggesting—at best—a “wait and see” attitude to their corporate clients. In addition, articles, books and reports about MDA were relatively few and far between—with the consequence that very few people were learning much about it.

What a difference a year or two can make! Now, many of those same corporations are eagerly downloading the latest versions of EMF and its many add-ons, or working with the wide range of advanced development tools hosted on EMF. Either way, they are effectively moving MDA right into the core of the software development mainstream. Meanwhile, books and articles about both EMF and MDA are starting to proliferate.

In many ways, the way that MDA is now moving into the corporate mainstream via EMF is reminiscent of the way that object-oriented programming once moved into the mainstream via Java. Before Java, there were many object-oriented languages, but all of them were supported only by niche, proprietary products with little market awareness or penetration. Once Java became available for free, it rapidly became the de facto standard not only for object programming but also for advanced programming in general.

MDA now stands at a similar juncture. The early proprietary MDA products never developed more than a niche market. But as the Eclipse platform is rapidly becoming ubiquitous worldwide, it is EMF—based on MDA—that is becoming its de facto standard development environment. As a result, it may not be so very long before MDA becomes the de facto standard approach for software development as well.

Michael Guttman is CEO of The Voyant Group, LLC, a U.S.-based IT consultancy focused on enterprise modeling. He is a regular columnist for Software Magazine and the co-author of Real-Life MDA (Elsevier, 2006). Philipp Kutter is a technology partner at Montages, a Switzerland-based IT consultancy focused on advanced modeling technologies. He can be reached kutter@montages.com. Contact Michael Guttman at mguttman@thevoyantgroup.com.