Understanding The Unified Modeling Language

Sinan Si Alhir − Understanding the Unified Modeling Language (UML)

Understanding the Unified Modeling Language (UML)
By Sinan Si Alhir
Sinan Si Alhir (salhir@earthlink.net, http://home.earthlink.net/~salhir) is a consultant and author of "UML in a
Nutshell" (O'Reilly and Associates, Inc., 1998).
Published in "Methods & Tools" (April 1999) − An international software engineering digitalnewsletter published by
Martinig & Associates.

Introduction
Organizations compete in a global market that is characterized by opportunities and risks where ongoing business and
technological change fuel ever−increasing competition. Organizations must not only manage change and the
complexity that results from adapting to change, but capitalize on the lessons learned, best practices, andknowledge
gained through this evolutionary process. The importance and criticality of knowledge has given way to the
Knowledge Revolution. This revolution can be characterized by the radical and fundamental paradigm shift that is
occurring within the business and technology industries where an organization's application of knowledge defines its
competitive advantage. Organizations can no longer onlyrely on physical muscle and size, but must harness
intellectual capital and creativity to be successful. Knowledge takes on many forms, however, its value is
demonstrated through its application and the realization of solutions to problems. If knowledge is captured and
reapplied, an organization is enabled to become even more competitive and proactive, rather than reactive, to change
andcomplexity; thus, increasing an organization's probability of success. This raises the fundamental question of how
does an organization best capture, communicate, and leverage knowledge in order to gain a competitive advantage?
Historically, organizations have attempted various methods for procuring intellectual capital. Within the information
system and technology industry, we have encountered theuse of structured techniques to minimize the impacts of
change and complexity, the use of Computer Assisted Software Engineering (CASE) tools to automate the
development process, the use of business reengineering techniques to optimize organizational processes, the use of
object−oriented techniques to facilitate reuse, the use of patterns to capture solutions to recurring problems, and theuse of components to actualize reusable parts. Inherent to these techniques is the encapsulation of knowledge.
With the emergence of the Unified Modeling Language (UML) from Rational Software Corporation and the Object
Management Group (OMG), it is very conceivable that such a language that unifies the many threads and
incarnations of the Knowledge Revolution is the most viable means fororganizations to best realize a competitive
advantage via capturing, communicating, and leveraging knowledge. Rational Software Corporation and three of the
most prominent methodologists in the information systems and technology industry, Grady Booch, James Rumbaugh,
and Ivar Jacobson (the Three Amigos) originally conceived the UML. The UML emerged from the unification that
occurred in the 1990sfollowing the "method wars" of the 1970s and 1980s to gain significant industry support from
various organizations via the UML Partners Consortium and be submitted to and adopted by the OMG as a standard
(November 17, 1997).
The UML is a modeling language for specifying, visualizing, constructing, and documenting the artifacts of a
system−intensive process.
• Within a system−intensive process, amethod is applied as a process to derive or evolve a system.
• As a language, it is used for communication. That is, a means to capture knowledge (semantics) about a
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Sinan Si Alhir − Understanding the Unified Modeling Language (UML)
subject and express knowledge (syntax) regarding the subject for the purpose of communication. The subject
is the system under discussion.
• As a modeling...