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From Inception toElaboration

Chapter 8

Applying UML and Patterns

-Craig Larman

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Objectives Elaboration is the initial series of

iterations during which the team does

the following Serious investigation

Discover & stabilize major requirements

Mitigate/retire risks ( business value )

Build core architecture elements

Estimate overall schedule and resources

Establish a supporting environment

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Inception - Artifacts and

Activities (1)

Short Requirements workshop

Naming most actors, goals, use cases

Keep use cases brief (10-20% are infully dressed)

Identify most risky & influential qualityrequirements

First version of SupplementarySpecification and vision are written

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Inception - Artifacts and

Activities ( 2 )

Risk list (including deadlines on demo)

Technical feasibility investigation (does therequirements supported by our used technology? )

UI oriented prototypes to clarify vision Buy/build/reuse components (ex:

recommendations to buy a tax calculator)

High-level candidate architecture (a rough estimate

of various accessories; a java front end? ) Plan for the first iteration

Candidate tools list

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Elaboration - Key Ideas

Not a waterfall model !

Two to six weeks for each iteration

Timeboxed iterations (deadlines shouldbe strictly maintained)

Each iteration products ends in a stable

and tested release

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Architecture

Prototype/Baseline

Not a partial system

Evolutionary prototype of final product

Dont create throw-away prototypes

Production subset of final system

Also called Executable Architecture

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Best Practices

Start programming early

Adapt based on feedback from tests,

users, developers Design, implement and test adaptively

Test early and realistically

Requirements and use case detailsthrough series of workshops (once periteration)

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Requirements and Iterations

ranking depends on.

Risk

-includes technical complexity and other

factors. Coverage

-whether all major parts are covered or not.

Criticality

-functions of high business value.

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Ranking

Rank work across iterations

High ranking scenarios in early iterations

(ex: process sales, logging, etc.) Rank adaptively

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UP Artifacts planning

Iteration Plan:- only the next iteration is

planned

Change Request:- plan written in greaterdetailed whenever necessary

Software Development Plan:- overall

requirement ranking is recorded.

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Artifacts starting in Elaboration

(this will not be completed rather

refined over iterations) Domain Model (conceptual class diagram)

Design Model

(logical design: class diagram, object oriented diagram, etc.)

Software Architecture Document(summary of ideas and motivations)

Data Model (database schemas..)

Test Model

Implementation Model (source code, databases and so on. )

Use-Case Storyboards and UI Prototypes (description of

user interfaces, navigations etc.

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Inception and Elaboration

Main output is a stable software

architecture, that enables quality

planning of Construction andDeployment

15 to 25 percent of total project cost

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You didnt Understand

Elaboration When

No Timeboxed schedule

Single Iteration

Most requirements already defined

No Risk mitigation/resolution

No Executable Architecture

Requirements Phase

Attempt full and careful design

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You didnt Understand

Elaboration When (2)...

Minimal feedback and adaptation

No early and realistic testing

Frozen Architecture

No Proof-of-concept programming

No multiple requirements workshops