01 (software) design an analogy with my closet

DISIM

Dept. of Information Engineering, Computer Science and Mathematics

University of L’Aquila, Italy

L01: (Software) Design: an analogy with my Closet!

Henry Muccini

henry.muccini@univaq.it

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Why do we need to Design our

Software

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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

decisionDiscussion

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Which type of construction design pattern shall I use?

Discussion

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Room Dimension

Room Characteristics

«The system and the enterprise provide

environments for, and constraints on , the software

architecture» [SAinPractice_Book]

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� 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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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 ->