HybridTransformation ModelingIntegrating a Declarative with an Imperative

Model Transformation Language

Pieter Van Gorppieter.vangorp@ua.ac.be

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OverviewCase Study

Conceptual Model Robustness Model

Imperative Approach Story Diagrams Flexible Too Low Level

Declarative Approach Triple Graph Grammars Compact Too Generic

Hybrid Approach Story Diagrams + TGG rules Expressive and Compact

Language Integration Metamodel Merging Metamodel Mapping

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Case Study

Conceptual Model

Robustness Model

4UML Profiled Models as Graphs

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Sample Constraint (Informal Version)

All classes from the conceptual model should correspond to entities in the robustness model.

Their attributes and attribute types should correspond.

Both internal types and library types should be supported.

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Overview

• Case Study• Imperative Approach

- Story Diagrams

• Declarative Approach• Hybrid Approach• Language Integration

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Imperative Approach:Story Diagrams

89 -- Evaluate whether each class in the conceptual model traces to

90 -- an entity in the robustness model

91 let eachClassTracesToAnEntity(): Boolean=

92 conceptualmodelTracesToRobustnessmodel() and -- ’rm’ not Undefined

93 allClassesFromModel(cm)->forAll(cmc|

94 allClassesFromModel(rm)->exists(rmc|

95 this.traceabilityLinks->select(oclIsKindOf(Class2Entity))->exists(l|

96 l.node->contains(cmc) and

97 l.node->contains(rmc)

98 )

99 )

100 )

Any interaction pattern can be implemented:

• setFocus• chooseAlternative• ...

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Story Pattern: “Is the Class related to an Entity?”

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Can be abstracted by TGG rules..

• Too low-level• Recurring Patterns

- Story diagram for creating elements- Story diagram for incremental update- Story diagram for manual resolution- ...

Problem

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Overview

• Case Study• Imperative Approach• Declarative Approach

- TGG Rules

• Hybrid Approach• Language Integration

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Classes to Entities

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Handling Internal Attribute Types

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Handling External Attribute Types

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Problem

• Overlapping Applicability

• Need user decision to resolve

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Overview

• Case Study• Imperative Approach• Declarative Approach• Hybrid Approach• Language Integration

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Solution• Adding a rule with higher preference

- Application condition: situation (6) or (8)- Effects:

• user interaction• delegate to appropriate TGG rule

- Arbitrary user interaction and control flows• story diagrams

• Resulting language: Hybrid- Declarative:

• TGG rules fully supported• Staged: rules are ordered

- Imperative: • Calls & branches in rules

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Making TGG rules Callable

• First State- Match nodes that are bound in the controlled TGG rule

• Second State- Call to the controlled TGG rule

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Controlled Triple Graph Grammars

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Language Integration

• Case Study• Imperative Approach• Declarative Approach• Hybrid Approach• Language Integration

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Metamodel Merging VS Mapping

• Hybrid Language: TGGs merged with SDM• Alternative: Strict mapping from TGGs to SDM

- With traceability (=> bootstrap desirable?)- User interaction implemented by manually completing the

generated story diagrams

• Discussion:- What adds most value to the QVT approach?- What is most readable?- ...

Either approach would make TGGs more attractive than QVT

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Related Work• ATL- Not bidirectional, which reduces the declarativeness of a

called rule to... 0

• QVT: - Also 2 layer language architecture- May not be possible to merge relational and operational

• Choosing a TGG tool to extend...- Darmstadt: advantage of JMI compliance

• Wait for all operational rule derivations?

- Paderborn: advantage of completed incrementality• Generate JMI wrappers?

- Aachen: advantage of alternative approach to user interaction• Standard Compliance?

• Why not share what is no contribution anymore?

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Conclusions• Hybrid Language reconciles:

- Compactness of TGTSs with- Expressiveness of Story Diagrams

• Language Engineering:- Metamodel Merging:

• Advantage: no confusion about semantics of TGG rules• Implementation:

- Minimal modification to rule derivation strategy (add <<bound>> nodes)

- Metamodel Mapping:• Advantage: no “details” on TGG level• Implementation:

- Rule derivation HOT needs to generate traceability links

- No hard guidelines (yet)

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Thanks for your Attention

Questions?pieter.vangorp@ua.ac.be

http://www.fots.ua.ac.be/~pvgorp/research/