A Generative Approach to Model Interpreter Evolution

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A Generative Approach to Model Interpreter
Evolution

• Jing Zhang, Jeff Gray, and Yuehua Lin
• zhangj, gray, liny _at_ cis.uab.eduDept. of
  Computer Information Sciences
• University of Alabama at Birmingham
• http//www.cis.uab.edu/softcom/

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Evolution of models and interpreters in terms of
meta-model changes
?MM The changes made to the meta-models ?M The
changes reflected in the domain models ?I The
changes reflected in the model interpreters
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Example Old/New Metamodel and model
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Example Old/New Interpreter
CBuilderAtom GetStartState(
CBuilderModel StateDiagram)
CBuilderAtom startstate null const
CBuilderAtomList states
StateDiagram-gtGetAtoms("State") POSITION
posstates-gtGetHeadPosition() while(pos)
CBuilderAtom st
states-gtGetNext(pos)
CBuilderConnectionList cons
st-gtGetInConnections("Transition")
if ( cons null ) if (
startstate null)
startstate st else
ltltERROR more than one state
has no InConnectionsgtgt ASSERT (
startstate !null ) return startstate
CBuilderAtom GetStartState(
CBuilderModel StateDiagram) const
CBuilderAtomList startstates
StateDiagram-gtGetAtoms("StartState")
ASSERT(startstates-gtGetCount()1)
CBuilderAtom startstate
startstates-gtGetHead()
return startstate
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Technical Challenges

• Lack of formally-written model interpreter
• Different developers may program interpreters in
  various ways
• Hard to maintain and evolve such subjective
  realizations of model interpreters
• Lack of formal specification for metamodel
  transformation
• Metamodel transformation specifications must
  include the entire knowledge for the underlying
  interpreter evolution
• ?MM ?I
• Lack of support for parsing and invasively
  transforming program source code from
  higher-level models.

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• Utilize a mature program transformation engine
  The Design Maintenance System (DMS)

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Model Interpreter Evolution Architecture (MIEA)
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DMS rewriting rules for evolving intepreter(1)

• Differences of names for any model entities,
  relationships and attributes

rule ChangeName (ididentifier)
expression_statement -gt expression_statement
"\id -gt GetModels(\State\")" -gt "\id -gt
GetModels(\StartState\")".
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DMS rewriting rules for evolving intepreter(2)

• Differences of model types

rule ChangeModelType (ididentifier)
expression_statement -gt expression_statement
\id -gt GetAtoms(\State\) -gt \id -gt
GetModels(\State\).
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DMS rewriting rules for evolving intepreter(3)

• Differences of attribute types

rule ChangeAttrType ()
declaration_statement -gt declaration _statement
CString State_Text
-gt int State_Text.
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Conclusion

• Ideal Goal
• Support the (semi)-automation of model
  interpreter evolution in terms of metamodel
  changes and modeling API changes
• Proposed Solution
• Model Interpreter Evolution Architecture
• Obstacles
• Informal model interpreter
• Hard to maintain the fidelity mapping of
  high-level abstract models to the low-level
  source code
• Possible solution approaches to be investigated
• Attach program rewriting rules to the existing
  model transformation specification
• Develop a new high-level specification for model
  transformation that can generate the rewriting
  rules
• Investigate an intelligent model comparison
  technique to generate the rules through human
  interactions

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Thank You !!
Questions ??