The means of production
“It's now been recognized that tools for architects have failed in the marketplace, repeatedly, because architects don't want anyone else's way of doing things, canned. What they want is something that's fluid and can evolve. That means we're building the factory platform and runtime, and evolving the DSL tools. We're also now working with Patterns and Practices as a provider of instances. The idea is that the instances they provide will be customizable and extensible, and the factory architecture is such that they’re building blocks, so rather than focus on composing components and services, we focus on composing the means of producing components and services,” says Greenfield.
What Greenfield calls a “runtime” is the piece that takes the factory that you have acquired, written or adapted, and executes it within Visual Studio. Currently, this is called the Guidance Automation Extensions, or GAX. The factory authoring tool is called the Guidance Automation Toolkit (GAT). Using these tools, you can create automated activities called Recipes, along with wizards and templates. The DSL tools let you add visual modelling to your factory. These pieces are used by the four software factories now shipping, which cover Web Clients, Smart Clients, Mobile Clients, and Web Services, and are free downloads. However, Greenfield describes the current runtime as “primitive” and promises something better in future.
There is also the question of why Microsoft is not using the standardised Universal Modelling Language (UML) and its associated Model-Driven Architecture (MDA) to speed productivity. “We are the UML guys, that’s the funny part of it,” says Greenfield. “I was one of the chief architects at Rational; I spent a lot of time deeply steeped in the UML and in the committee work in the OMG. Other guys on team go deeper than I do. Steve Cook, for example, was really the father of OCL [Object Constraint Language], and wrote the green paper for the family of languages which spawned the UML 2.0 effort. We’ve got deep roots.”
U and non-U
Despite (or because of) his background, Greenfield is now dismissive. “The UML is a collection of useful abstractions,” he says. “Unfortunately it’s been peddled as a universal modelling language, but the U never stood for Universal. We subscribe to Michael Jackson, author of Problem Frames, who says that there is no such thing as a universal solution. It's a childish approach. This is where the Universal Modelling Language marketing pitch fails. UML was never properly extensible. It also has the problem that it was designed by a committee.
Aside from that, things like state charts and sequence charts and activity graphs are very useful abstractions. UML becomes for us a repository of useful notational conventions and core abstractions, but in its form as packaged and delivered, not terribly effective. We view factories versus MDA the same way. MDA says you’ve got three viewpoints, CIM, PIM and PSM. The same viewpoints apply to everything, whether you’re building eBay or a mobile device application. We don’t buy that. They’re different things.”
It is easy to criticize the UML; but can Microsoft show that its new software factories are more effective than previous efforts to improve developer productivity? Greenfield mutters about customer feedback, and then talks about how packaged applications like SAP have replaced development from scratch in ERP (Enterprise Resource Planning).
"The general principle of having pre-defined architectures, components, skeletal applications and pre-defined database schemas, and a process to adapt that to a customer - that’s working,” he says. That’s true, but it’s more a validation of “buy versus build” than proof of the viability of software factories. This considerable effort may prove no more than an interesting experiment.
That said, it's a bold and intriguing vision. Greenfield will not be pressed on times or dates; he merely says that this is where Microsoft is heading
Perhaps it is reasonable, then, to expect a more fully realised version of the current factory platform in the high-end editions of the next Visual Studio. ®