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Testbed for Aspect-Oriented Software Development: TAO

Phil Greenwood and numerous other contributors

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Various Barriers

• Available systems lack complete documentation.• Difficult to find AO and non-AO implementations for the

same system.– Need to guarantee that the non-AO and AO decompositions are

good ones.

• Difficult to find or develop from scratch a plausible “benchmark”.– many risks: time-consuming task, inherent bias, etc…– collaboration is the only alternative left.

• Quantitative or qualitative indicators are often NOT ready for use.

• Replication of studies becomes a pain.

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A Testbed for AOSD

• Towards more scientific and cohesive research.– Serve as a communication and collaboration vehicle

• Achieve widely-accepted exemplars, indicators, and data that can be reused and refined.

– Facilitate the identification of “unknown” problems and benefits inherent to AOSD.

• Effects throughout the lifecycle.– Bottlenecks specific to certain SE phases and their

transitions.

– Accelerate the progress in the area by offering context to pinpoint technique-specific problems.

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Testbed Elements

Design Stability Study

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Completed Studies

• “On the Impact of Aspectual Decompositions on Design Stability: An Empirical Study” ECOOP 2007.

• “A Comparative Study of Aspect-Oriented Requirements Engineering Approaches” ESEM 2007

• “On the Impact of Evolving Requirements-Architecture Dependencies: An Exploratory Study” CAiSE 2008

• “Pointcut Rejuvenation: Recovering Pointcut Expressions in Evolving Aspect-Oriented Software” ICSE 2009 (under review)

• “Investigating Pointcut Fragility: An Exploratory Study” AOSD 2009 (under review)

• “Semantic vs. Syntactic Compositions in Aspect-Oriented Requirements Engineering: an Empirical Study” AOSD 2009 (under review)

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On the Impact of Aspectual Decompositions on Design Stability: An Empirical Study

• Multi-dimensional analysis of AO and OO implementations which included:– Modularity Sustenance.

– Observing ripple effects.

– Aspect types which are susceptible to instability.

– Satisfaction of basic design principles through the releases.

• Outcome Highlights– AO solutions required less intrusive modifications.

– Aspectual decompositions satisfy the open-closed principle.

– AO modifications tended to propagate to seeming unrelated modules.

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A Comparative Study of Aspect-Oriented Requirements Engineering Approaches

• Comparison of four eminent AORE approaches which involved analysing:– Time effectiveness (person-minutes).– Accuracy of their produced outcome.

• Precision and recall of the models produced .– Identifying the activities that are the main bottlenecks in AORE

approaches.

• Main outcomes.– Composition specification and conflict analysis activities are the most

time consuming.– Common framework for comparing AORE approaches in order to

facilitate future AORE evaluation exercises.

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On the Impact of Evolving Requirements-Architecture Dependencies: An Exploratory Study

• The goal of the analysis was to characterize:– How the nature of requirements’ dependencies can lead to tight or

loose interconnections with architectural elements.– The most architecturally-significant requirements’ dependencies.– How the requirements’ dependencies evolve during maintenance

changes.

• Significant findings:– Conditional and service dependencies are architecturally significant.– Infrastructure dependency has high impact for adaptive change.– Rare to have isolated dependencies pull the architecture in various

directions.