UML Weekend Crash Course™ - To Parent Directory

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Sunday Afternoon
design, and modeling of the software. Without proper analysis, many of the Web projects did
not meet the business requirements they were designed to support. Without proper design,
many of the systems were difficult to adapt and rescale as the business requirements or number
of users changed. Without a model of the system, such as a UML model, many of the Web
systems were difficult to trace and maintain.
The dot-com crash did not demonstrate that the Web was less useful than people thought;
instead it demonstrated that successful Web development necessitates better business planning
and better software analysis and design. As a result, the importance of utilizing the
UML in Web development is clearer than ever. This session and the two sessions following
explore how the UML can be applied to Web development. This session presents an introduction
to Web development concepts for those readers who are new to Web development.
Session 28 explores design and architectural issues of Web application development. Both of
these sessions will use UML diagrams to demonstrate the Web concepts. Session 29 will bring
the concepts together by modeling a Web application case study using the UML.
Issues in Using the UML in Web Development
The UML was developed primarily for traditional object-oriented application development.
Web applications have several differences from traditional object-oriented applications that
require adapting the UML to work with the Web architecture model.
Some of the key aspects of Web development that affect the use of the UML models
include
Web applications almost always involve markup languages such as HTML and XML
that are not inherently object-oriented. Session 28 considers some mechanisms that
can be used to show an object representation of markup language documents using
a Class diagram.
Web applications are inherently very network-dependent architectures.
Consequently, Deployment diagrams are very helpful for modeling Web applications.
Web applications frequently involve a wide variety of different technologies integrated
together. Component diagrams can be very helpful for showing the relationships
between these architectures.
Many Web technologies are not object-oriented, which may lead the reader to think
that Sequence diagrams, Collaboration diagrams, Object diagrams, and Class diagrams
would be of little use. Nonetheless, these modeling techniques can support the development
of highly modular designs that are more easily developed and maintained.
Tip
This session is designed to give readers with no Web development experience
a brief introduction to these technologies. If you already have done a lot of
Web development, you’ll probably want to skim over parts of this session. Take
note of how the UML is used in this chapter to show the Web architecture.
Basic Web Architecture and Static Web Content
For simplicity, first consider the static Web content, which is the Web content that never or
infrequently changes. Suppose that your company wants to have a Web site that has some