Datasheet

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Part I ✦ An Introduction to UML
IntelliCorp, IBM, ICON Computing, MCI Systemhouse, Microsoft, Oracle, Rational
Software, TI, and Unisys. The result of their efforts was published in January 1997
as UML 1.0.
At the same time, another group of companies (IBM & ObjecTime, Platinum
Technologies, Ptech, Taskon & Reich Technologies, and Softteam) was working on
and submitted another proposal for UML. And, exemplary of the UML history, the
alternative proposal was viewed not as competitive, but collaborative. The new
team joined the UML Partners consortium and the work of the two groups was
merged to produce UML 1.1 in September 1997. Since then, the OMG has assumed
formal responsibility for the ongoing development of the standard, but most of the
original consortium members still participate.
In reading this brief history you’ve probably noticed that this all happened pretty
fast. The drive to deliver the final version so quickly had its consequences. While
the architecture infrastructure and even the superstructure were relatively well
defined, some problems remained. For example, the Activity diagram did not have
the ties to the state machine semantics required to support all of the features and
notations needed for real business modeling. Also, many of the Standard Elements
were added hastily and had not been fully defined. Most important, the meta-
modeling approach fell short of the desired implementation, making it difficult
to align UML with the Meta-Object Facility (MOF), a foundation technology in
the OMG’s MDA strategy. Fortunately, the standard is still evolving.
The OMG set up a Revision Task Force (RTF) to oversee the ongoing evolution of
the UML standard. The RTF is responsible for addressing all questions, changes,
and enhancements to UML and for publishing subsequent releases. To date, the
RTF has taken up more than 500 formal usage and implementation issues submitted
to the OMG for consideration. In fact, you can submit your own suggestions and
comments on existing issues to
[e-mail].
The standard has since progressed through version 1.3 (1.2 was a purely editorial
revision) and on to version 1.4. The most recently adopted specification
(September 2002) is version 1.4.1 with Action Semantics, which, as the name
implies, added action semantics to the 1.4 specification. Action Semantics is a criti-
cal element in the creation of executable UML models.
To learn more about Action Semantics, refer to Chapter 19.
The Goals and Features of UML
UML is designed to meet some very specific objectives so that it can truly be a stan-
dard that addresses the practical needs of the software development community.
Any effort to be all things to all people is doomed to fail, so the UML authors have
taken care to establish clear boundaries for the features of the UML.
Cross-
Reference
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