Stephen J. Mellor: Language

“Creating a modeling language that is also an executable language has long been a goal of the software community. Many years ago, in 1968 to be exact, while working with software components to successfully develop a telecommunications system, we created a modeling language that was the forerunner to UML. To model components we used sequence diagrams, collaboration diagrams, and state transition diagrams (a combination of state charts and activity diagrams). Our modeling language then seamlessly translated the component models into code. Each code component was in its turn compiled into an executable component that was deployed in our computer system. The computer system was a component management system—thus we had "components all the way down."”

Stephen J. Mellor

Source: Executable Uml: A Foundation for Model-Driven Architecture, 2002, p. xxiii: Foreword.

Way , Communication

“Executable UML is at the next higher layer of abstraction, abstracting away both specific programming languages and decisions about the organization of the software so that a specification built in Executable UML can be deployed in various software environments without change.”

Stephen J. Mellor

Source: Executable Uml: A Foundation for Model-Driven Architecture, 2002, p. 5.

Decision , Change

“MDA per se is relaxed about exactly what models it transforms, so long as the modeling language in which the models are expressed can be defined.”

Stephen J. Mellor

Source: MDA Distilled. Principles of Model-Driven Architecture, 2003, p. 36.

“What's the point of having metamodels, and why should you care? Because models must be stated in a way that yields a common understanding among all involved parties, we need a way to specify exactly what a model means. Metamodels allow you to do just that: They specify the concepts of the language you're using to specify a model.”

Stephen J. Mellor

Source: MDA Distilled. Principles of Model-Driven Architecture, 2003, p. 37.

Way , Understanding

“I was astonished to be invited to what became the meeting that originated the Agile Manifesto because my work had always been based around building models… The other signatories were kind enough, back in 2001, to write the manifesto using the word “software” (which can include executable models), not “code” (which is more specific.) As such I felt able, in good conscience, to become a signatory to the Manifesto while continuing to promote executable modeling. Ten years on we have a standard action language for agile modeling.”

Stephen J. Mellor

Mellor (2011) " A Personal Reflection on Agile Ten Years On http://www.infoq.com/articles/personal-reflection-agile-ten-years-mellor" in: InfoQ, Feb 11, 2011.

“What's really going on is that Executable UML is a concurrent specification language.”

Stephen J. Mellor

Source: MDA Distilled. Principles of Model-Driven Architecture, 2003, p. 96.