Using Ontologies for Flexibly Specifying Multi-User Processes ICSE - - PowerPoint PPT Presentation

Using Ontologies for Flexibly Specifying Multi-User Processes

ICSE 2010 Workshop on Flexible Modeling Tools Cape Town, South Africa, 2 May 2010 Gregor Gabrysiak, Holger Giese and Andreas Seibel System Analysis and Modeling Group Hasso Plattner Institute University of Potsdam

Formal Tools

Pros

• automatic detection of errors
• maintenance throughout the

model is simple

• reusable throughout a project

Cons

• restricted by metamodel
• early commitment
• overhead for small projects

Figure: UML Model (MS Visio)

Gregor Gabrysiak, FlexiTools 2010, 2 May 2010 Formal vs. Informal Tools 2

Informal and General-Purpose Tools

Pros

• easy to use
• everything can be captured
• degrees of freedom are

similar to whiteboards Cons

• no metamodel
• changing references
• presentable, rarely reusable

D A B1 B2 C

Figure: Process Model (Keynote)

Gregor Gabrysiak, FlexiTools 2010, 2 May 2010 Formal vs. Informal Tools 3

Bridging the Gap

Formal Informal Flexible Metamodel Ontologies as Flexible Metamodels

• less restrictive
• missing concepts can be added on demand
• capable of capturing the modeler’s intent
• a model can always be interpreted with its

corresponding metamodel

Gregor Gabrysiak, FlexiTools 2010, 2 May 2010 Introducing Ontologies 4

Using a Formal Modelling Tool

customer:Role boss:Role assistant:Role

M2 M1

<<instanceOf>> <<instanceOf>> <<instanceOf>> Gregor Gabrysiak, FlexiTools 2010, 2 May 2010 Introducing Ontologies 5

Metamodel (Formal Tool) User Generated Model

Extending the Meta Model

jane:Boss john:Assistant max:Customer

M1

<<instanceOf>> <<instanceOf>> <<instanceOf>>

M2

Gregor Gabrysiak, FlexiTools 2010, 2 May 2010 Introducing Ontologies 6

Metamodel Project- Specific User Generated Model

Using Ontologies as Meta Model

M1 M2

<<instanceOf>> <<instanceOf>> <<instanceOf>> jane:Boss john:Assistant max:Customer Gregor Gabrysiak, FlexiTools 2010, 2 May 2010 Introducing Ontologies 7

Basic Ontology Project- Specific User Generated Model

Creating Behavioral Specifications I

Using the terminology defined in the ontology, an analyst can...

• describe an observed situation
• describe the follow-up state
• the difference between both specifies an action
• specified in the terminology defined in the ontology

receiver

Gregor Gabrysiak, FlexiTools 2010, 2 May 2010 Modelling with Ontologies 8

Initial state Follow-up state

Creating Behavioral Specifications II

receiver

• ++

,"-").", ++ /"#$", ++%%(00(-1"$ %2%&'()* 01)/%2%34/056", 7%2%8//)/0(#0 %2%9,5:5/(* 1(/

!"#$%9,5:5/(*

Gregor Gabrysiak, FlexiTools 2010, 2 May 2010 Modelling with Ontologies 9

So, what do we have?

• behavioral and situational

specification of a process

• formal specifications that

can be simulated

• all specifications reference

elements of the flexible metamodel

• specified in the

terminology defined in the

• ntology
• specification is affected by

changes in the ontology

++ ,"-").", ++ /"#$", ++%%(00(-1"$ %2%&'()* 01)/%2%34/056", 7%2%8//)/0(#0 %2%9,5:5/(* 1(/

!"#$%9,5:5/(*

Gregor Gabrysiak, FlexiTools 2010, 2 May 2010 Modelling with Ontologies 10

So, what do we have?

• behavioral and situational

specification of a process

• formal specifications that

can be simulated

• all specifications reference

elements of the flexible metamodel

• specified in the

terminology defined in the

• ntology
• specification is affected by

changes in the ontology

++ ,"-").", ++ /"#$", ++%%(00(-1"$ %2%&'()* 01)/%2%34/056", 7%2%8//)/0(#0 %2%9,5:5/(* 1(/

!"#$%9,5:5/(*

Gregor Gabrysiak, FlexiTools 2010, 2 May 2010 Modelling with Ontologies 10

So, what do we have?

• behavioral and situational

specification of a process

• formal specifications that

can be simulated

• all specifications reference

elements of the flexible metamodel

• specified in the

terminology defined in the

• ntology
• specification is affected by

changes in the ontology

++ ,"-").", ++ /"#$", ++%%(00(-1"$ %2%&'()* 01)/%2%34/056", 7%2%8//)/0(#0 %2%9,5:5/(* 1(/

!"#$%9,5:5/(*

Gregor Gabrysiak, FlexiTools 2010, 2 May 2010 Modelling with Ontologies 10

When Working with Flexible Metamodels...

We have to deal with ...

• addition, modification, and removal of
• classes, properties, methods, and associations

+

2

Gregor Gabrysiak, FlexiTools 2010, 2 May 2010 Handling Ontology Modifications 11

When Working with Flexible Metamodels...

We have to deal with ...

• addition, modification, and removal of
• classes, properties, methods, and associations

+

2

Worst Case Scenario modeled specifications become unreadable with modified metamodel

Gregor Gabrysiak, FlexiTools 2010, 2 May 2010 Handling Ontology Modifications 11

Modifications of the Ontology

Addition Removal Modification Class

• Property
• Association
• Gregor Gabrysiak, FlexiTools 2010, 2 May 2010

Handling Ontology Modifications 12

Addition of any new Element

• not referenced yet =

⇒ no action necessary

• save as often as possible
• small deltas between versions
• old version of the ontology is kept
• when saving, IDs can be added

Modifications of the Ontology

Addition Removal Modification Class

• Property
• (user assisted)
• Association
• (user assisted)
• Gregor Gabrysiak, FlexiTools 2010, 2 May 2010

Handling Ontology Modifications 12

Removal of any referenced Element

• Class: dangling references are redirected (recursively) to

the corresponding superclass

• Property: either delete references or move to superclass
• Association
• pointing to deleted class: redirect to superclass
• else: either delete references or propose substitutes

Modifications of the Ontology

Addition Removal Modification Class

• (user assisted)

Property

• (user assisted)
• (user assisted)

Association

• (user assisted)
• (user assisted)

Gregor Gabrysiak, FlexiTools 2010, 2 May 2010 Handling Ontology Modifications 12

Modification of any referenced Element

• modeler’s intent is unclear
• syntactical change (Bosss becomes Boss):
• same concepts apply, references still valid
• IDs can be used to redirect from Bosss to Boss
• semantical change (+getX() becomes +setX()):
• different concepts apply, references invalid
• remove old version + add new version

Conclusions

++ ,"-").", ++ /"#$", ++%%(00(-1"$ %2%&'()* 01)/%2%34/056", 7%2%8//)/0(#0 %2%9,5:5/(* 1(/

!"#$%9,5:5/(*

2

b:Role

+age: int

this:Customer2

+ + +

value: int

+

• ontologies as flexible metamodels
• concepts for handling metamodel changes
• implementation in Eclipse & EMF
• automatic reload of changes in metamodel
• Addition of elements fully functional

Gregor Gabrysiak, FlexiTools 2010, 2 May 2010 Handling Ontology Modifications 13