Information Technology Reference
In-Depth Information
Chapter 3
Modeling with UML
The demand for software has risen tremendously since the early days of software
engineering; and, as basic economics teaches us, when the demand for a product
rises, so does the value associated with that product. This increase in the value of
software has encouraged the software industry to seek out and create ever more
efficient methods of software production. Much of the previous two chapters have
focused on this never ending pursuit of higher quality software with lower costs
and shorter production times. We have outlined many of the concepts central to
this goal, including one of the foundations of the object-oriented paradigm,
abstraction. Abstraction allows for the useful classification of real world phe-
nomena. The Unified Modeling Language (UML), a graphical system for creating
models that has become the ''de facto standard for object-oriented modeling'', is
one of the central tools used to put this concept into practice (Sommerville
2004
).
3.1 Introduction to the Unified Modeling Language
As the demand for software has quickly risen, so has the relative complexity of
many software products. These increasingly complicated projects require more
planning, more engineers, and more code. As this growth continues, clear com-
munication becomes ever more vital to the success of a software project. Standard
modeling systems were developed to meet this need. The foremost of these is
UML, which has emerged over the last decade as the most popular and is today, in
essence, the standard ''software blueprint language'' (Miller
2003
). UML allows
everyone involved in software project, from the client to business analysts and
from designers to programmers, to have a common understanding of the software
being developed. It also allows for the use of a common vocabulary when dis-
cussing that software. Furthermore, UML has its foundations in the object oriented
paradigm, and thus the central concepts of software engineering are essentially
''built in'' to the system.
The foundations of UML were laid in the mid-1990s when Booch and
Rumbaugh began the unification of two different modeling systems: the Booch
