Datasheet

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Chapter 1 What Is UML?
The next section explains the objectives and the scope of the UML, the fundamental
features provided by the UML, and discusses the role of the OMG in the manage-
ment and ongoing development of the UML as a part of its MDA strategy.
The goals of UML
The OMG knows that the success of UML hinges on its ability to address the widely
diverse real-world needs of software developers. The standard will fail if it is too
rigid or too relaxed, too narrow in scope or too all-encompassing, too bound to a
particular technology or so vague that it cannot be applied to real technologies. To
ensure that the standard will, in fact, be both practical and durable, the OMG estab-
lished a list of goals.
UML will
Provide modelers with a ready-to-use, expressive, and visual modeling lan-
guage to develop and exchange meaningful models.
Furnish extensibility and specialization mechanisms to extend the core
concepts.
Support specifications that are independent of particular programming lan-
guages and development processes.
Provide a formal basis for understanding the modeling language.
Encourage the growth of the object tools market.
Support higher-level development concepts such as components, collabora-
tions, frameworks, and patterns. (UML1.4 specifications)
Each of these goals is discussed in detail in the following sections.
Goal 1: Provide modelers with a ready-to-use, expressive, and visual
modeling language to develop and exchange meaningful models
UML must be defined at a level that allows it to be used as-is off the shelf. Modelers
should be able to start building diagrams without first customizing the notation to
their development environment, programming language, or application. The model-
ing language should work equally well for Java and C++, for accounting and aviation.
To accomplish this, the standard has to define the semantics of the modeling lan-
guage as well as the visual representation of the language. Semantics provide the
rigor that ensures the consistent application of the models and model elements.
A consistent visual representation of the model elements facilitates adoption and
use of the modeling technique.
The standard also must be comprehensive but not exhaustive. It must include
all the core modeling elements common to most, not all, software projects. If it
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