Page 143 - DCAP308_OBJECT_ORIENTED_ANALYSIS_AND_DESIGN

Unit 11: Domain Analysis

Try to refine classes to increase sharing and improve structure. Notes
Some constructs won’t fit in model; You probably missed or miscast a general concept;
reexamine them & change model

Include exception, special case
Remove classes or association that seemed to be useful at first but now appears extra; you
can combine two classes in analysis can be combined

A good model have few small areas & don’t have extra details

11.4.2 Restating the Requirements

Most of real requirements will be part of model
Other requirements specify method of solution and should be separated if possible.
During analysis some requirements may appear to be incorrect & impractical; confirm
correction to requirements
Business expert verify it to make sure that it correctly models the real world
Final model serves as basis for system architecture, design & implementation.

11.4.3 Analysis & Design

Goal of analysis is to specify the problem without implementation details but it is impossible to
avoid all taints of implementation. There is no absolute line between various development
stages nor is there any such thing as a perfect analysis.
Self Assessment

Fill in the blanks:
14. .................... the analysis requires more than one pass to complete.
15. Final analysis is verified with requestor & .................... expert.

11.5 Summary

The goal of the domain analysis model is to analyze a problem without introducing bias
for implementation.
All classes must make sense in application sense; avoid computer aspects only consider
physical entities.
If two classes express same concept keep the most descriptive name. Names that describe
individual objects are attributes.

Prepare data dictionary for all modeling elements and describe scope of class, restriction
on its use, associations, attributes, operations.

If independent existence of element is important than its value, consider it as object.
Name is an attribute when it does not depend on context & it is not unique. Inheritance can
be added by generalizing existing classes into a superclass or by specializing a class into
subclasses (based on taxonomic relations).

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