This document uses an analogy of designing a closet to illustrate software design principles. It discusses factors to consider when designing a closet such as whether to buy a pre-made shelf or build your own. The document also covers drawing a design for the closet, choosing a construction pattern, addressing requirements like shelf weight capacity and cost, and incrementally improving the design to mitigate risks and learn from mistakes. The goal is to build a stable, functional closet structure.

1. L01: (Software) Design: an analogy with my Closet!
Henry Muccini
henry.muccini@univaq.it
DISIM
Dep.nt of Information Engineering, Computer Science and Mathematics
University of L’Aquila, Italy

2. The material in these slides may be freely reproduced
and distributed, partially or totally, as far as an explicit
reference or acknowledge to the material author is
preserved.
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Why do we need to Design our
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Drawing my closet

8. Shall I buy a pre-made shelf?
Shall I make it?
That translates into:
«Shall I buy the system from the market, or buy some
components and assemble the system I need!»
Many factors to be
analyzed to make such a
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decision
Discussion

9. Which type of construction design pattern shall I use?
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Discussion

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11. Room Dimension
Room Characteristics
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«The system and the enterprise provide
environments for, and constraints on , the software
architecture» [SAinPractice_Book]

12.  Build a stable, no crashing, structure
 Build shelves that can keep up to 40 kilos
 Cost = 0 (derived requirement)
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Drawing the closet design

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16. How to build the «central» element?
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How to make this
central element as
stable as possible??

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Buy vs. Build
Design Patterns
Design Decisions
Environmental Constraints
Risk mitigation
Incremental design
Resources
mistakes -> learn -> fix -> mistakes ->