Extending Methods to Express Change Requirements

1
Extending Methods to Express Change Requirements
PARIS 1
SORBONNE

• Anne Etien, Rébecca Deneckère, Camille Salinesi
• C.R.I.- Université Paris 1 - Sorbonne
• 90, rue de Tolbiac, 75013 Paris, France

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Introduction

• Situational Methods Engineering Versus
  Information System Evolution
• Specification of change requirements
• C. Rolland, C. Salinesi, A. Etien Eliciting Gaps
  in Requirements Change. To appear in Requirement
  Engineering Journal

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Plan

• Proposition improving any method to allow the
• expression of change requirements.
• The change requirements elicitation approach
• Extending the approach
• Example on the Orion method
• Conclusions

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The Change requirements elicitation approach
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The Generic Meta-Model
6
The Generic Gap Typology
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The Generic Gap Typology
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Extending the approach
Compound
Object
Link
target
Operator
source
has a
Time Horizon
Property
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Quality criteria

• Completeness
• Consistency
• Minimality
• Exhaustiveness
• Fitness for use
• Correctness

Completeness The typology must be expressive
enough to capture all essential aspects of
changes requirements
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Extended approach
Gap Typology for operator object
Extended Generic Meta-model
Generic Typology
Instance of
Generic Meta-model level
Part of
Instance of
Instance of
Instance of
?
As-Is Extended Meta-Model
To-Be Extended Meta-model
Specific Meta-model level
?
?
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Method extension process
Intention Goal that can be achieved by a
performance of an activity
Strategy way, manner to achieve a goal
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Method extension process
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Method extension process for Orion
Generic meta-model driven strategy
Start
By fitness for use strategy
Formalise core meta-model
Extension typology-based strategy
By minimality strategy
By consistencystrategy
Stop
Meta-model knowledge driven strategy
By completeness strategy
Extension formalization strategy
Define extension
By exhaustiveness strategy
By correctnessstrategy
By application of meta-model modification
operator strategy
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Example Formalise Core meta-model
Class Hierarchy
Has for source
Composite Link
Object
Simple
Has for target
Compound
Class
Method
Link
Super Class
Property
Has a
1
Has for target
Code
Root
Has a
Has for target
Is-A Link
Instance Variable
1
Order
Inheritance Link
Has for source
Has for source
Sub Class
1
Domain
Has a

Default Value

Shared Value
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Example Define Orion extension by the typology
based strategy
Formalise core meta-model
Extension typology-based strategy
Extension formalization strategy
Define extension
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Example Define extension by extension
formalisation strategy
Formalise core meta-model
Extension typology-based strategy
Extension formalization strategy
Define extension
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Example Application of the meta-model
modification operator strategy
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Example Verifying the quality criteria to stop
the process
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Conclusions

• Generic approach for change requirements
• Extension of the approach
• Situation Method Engineering Process
• Further investigations