a model-driven course on Petri-Nets, Metamodels and Graph Grammars

Pieter Van Gorppieter.vangorp@ua.ac.be

Hans Schippershans.schippers@ua.ac.be

Dirk Janssensdirk.janssens@ua.ac.be

Serge Demeyerserge.demeyer@ua.ac.be

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Myth of Formal Methods:• exhaustive proofs• high training required• hard to comprehend• expensive• ...

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Solution• Prevent spread of such myths into Industry• Variety of Courses apply Formal Modeling

- designing a distributed system: introduction to UML,- designing a compiler: advanced class diagrams, text grammars,- relational algebra,- B, Z, OCL, Hoare Logic, ...

• However: - always limited to one modeling language / formalism- no link between:

• “mathematical” languages• more human-friendly languages• source code

- students: formal methods not applicable in practical software engineering?• Therefore:

- New Model-Driven Engineering (MDE) Course- Software Development with Various Formalisms

Metamodeling and Model Transformation

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1. Designing the Course• Objectives• Tool Selection

2. Course Description• Teaching Methods• Evaluation Methods• Course Artifacts• Link to Objectives

3. Lessons Learned

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Objectives / Expected Learning Outcomes• “Based on formal specifications (logical specifications, statecharts,

Petri-Nets) the student should be able to build models expressing the intended functionality of a system, to analyse and to verify these models, and to generate a working implementation from them.”

• “The student should be able to express the intended functionality of a system from different viewpoints in different formalisms (Petri-Nets, Graph Grammars) and ensure particular properties (boundedness, consistency, ...) of such models. The student should use state-of-the-art transformation techniques (model animation, model translation and code generation) to integrate distinct models and relate them to a complete implementation. The student should experiment with metamodelling in this context, and acquire an understanding of the benefits and limitations of the 4-layer meta-data architecture.”

Designing the Course >>

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(Meta-)Modeling

Properties Transformations

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• DiaMeta- advantage: standard (MOF) compliant- interoperable with group's research tool- disadvantage: immature

• Tiger- advantage: “sexy” (Eclipse)- disadvantage: heavyweight, yet no MOF/EMF support (yet)

• AToM3

- advantages: self-containedness- disadvantage: non-standard

Tool SelectionDesigning the Course >>

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1. Designing the Course• Objectives• Tool Selection

2. Course Description• Teaching Methods• Evaluation Methods• Course Artifacts• Link to Objectives

3. Lessons Learned

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Teaching MethodsCourse Description >>

7x 11x

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• BlackBoard Assignments: 8

• Relaxed Deadlines- E-mail sumissions

• Incremental Assignments

- Prepared Solutions

• Assignment completion overview

• Three Evaluation Milestones

• Extra Examination:- Oral with written

preparation

EvaluationCourse Description >>

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1. Designing the Course• Objectives• Tool Selection

2. Course Description• Teaching Methods• Evaluation Methods• Course Artifacts• Link to Objectives

3. Lessons Learned

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Petri-Net Editor (I/II)Course Artifacts >>

All thinkingPh. 1: Forks on TablePh. 2: Forks on Table

Ph. 3: Forks on TablePh. 5: Forks on Table

Ph. 4: Forks on TablePh. 6: Forks on Table

......

Ph. 1 & 5 will start eating

Ph. 3: Could eat too

Ph. 4: Cannot start eating!

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Petri-Net Editor (II/II)Course Artifacts >>

Modeling a Visual Language Editor Modeling Language Structure (= metamodel)

>> as E/R or Class Diagram Modeling Concrete Syntax Some Python code required

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RailRoad Editor

...

...

Course Artifacts >>

...

Animation changes train location

14Graph Grammars (I/II)

15Graph Grammars (II/II)Train Animation:rewriting of abstract nodes

Train 2 Petri Transl.:Traceability

Train 2 Petri Translation:Out-Place MtoN rules

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1. Designing the Course• Objectives• Tool Selection

2. Course Description• Teaching Methods• Evaluation Methods• Course Artifacts• Link to Objectives

3. Lessons Learned

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Content<>ObjectivesCourse Description >>

Modeling Properties TransformationIntroduction

Papers, Discussion, Motivating Demo’s

C/E NetsP/T Nets

Colored Nets

PN MetamodelTrain Metamodel

SafetyDeadlocks?

PN AnimationTrain Animation

Discussion:Evaluation AToM3 GGs

Classification Papers“Beyond AToM3”

dq

PN ModelsTrain-to-PN

Next step:tracing back

analysis results

Generating Editors

Train Models

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1. Designing the Course• Objectives• Tool Selection

2. Course Description• Teaching Methods• Course Artifacts• Evaluation Methods• Link to Objectives

3. Lessons Learned

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Best Practices• Best Practices

- Feasibility Study- Expert Supervision- Start Small- Work Incrementally- Illustrate Applicability- Examples First- Problems First

Lessons Learned >>

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Planned Improvements• Planned Improvements

- Provide Tool Feedback

- Consider Alternative Tools

- Provide Integration Components• to Petri-Net Analysis Tools

- Extend Railroad Case Study

- Prepare Follow-Up Courses

Lessons Learned >>

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Industrial Relevance• Industrial Relevance

- Curriculum at University of Antwerp:• 3 Master Profiles:

- industrial, - educational,- or research profile.

• Course in BACH3 tradeoff!- Concrete alternatives:

(a) Use of UML code generator (transformations) in popular middleware context

(b) Building editors and transformationswithout middleware focus

- Why (b)?• tool internals look beyond marketing!• demand from automotive industry

Lessons Learned >>

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Conclusions• Course Format

» Conventional Lectures: Petri-Nets» Paper Discussions: MDE» AToM3 Lab Sessions

Integrated Case Study, Problems First

• Course Focus» Integration of Languages

• Course Evaluation» Content meets Objectives» BlackBoard Questionnaire: Students Excited!» Encouraging basis for other new MDE courses

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Thanks for your Attention

Questions?pieter.vangorp@ua.ac.be

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