Yu, et al.’s “A Model-Driven Development Framework for Enterprise Web Services” In proceedings of the 10 th IEEE Intl Enterprise Distributed Object Computing Conference (EDOC06) A summary

Agenda Context: 5 mins intro to MDD Summary of the main points in the paper: –The idea –The main contribution –Section by section summary Discussion –Some possibilities for improvement –The final grades!

MDD – the basic idea Raising the level of abstraction Main benefits: –“Closer” to the real concepts  Software specification and understanding are easier –Less bound to the underlying platform  Software maintenance is easier (“Model once, Generate everywhere”)

MDD – The Lingo Models –M1: Describe/Specify the real things Modeling languages –Notation, Syntax, Semantics Meta models and meta languages –M2: Describe the modeling language An XSD file is an M2, XML schema is the meta language

MDD – The Lingo (2) Model Transformation: –Same idea as compiling just more difficult, due too the wider gap of abstraction –Is done at the meta level Elements and relationships mappings –Involves: A set of mappings (Transformation Rules), expressed in a certain transformation language A transformation engine (like a compiler)

The paper - Idea Start with EDOC models –Enterprise Distributed Object Component, a UML-based language designed for distributed, component-based systems Automatically generate the WDSL files (Not the web services themselves) for all the Web Services involved in the models

The paper – Contributions A set of EDOC  WDSL transformation rules –Could be used for what it is designed for (of course) –Serve as a a concrete example of MDD Meta models for both EDOC and WDSL were given in UML notations How entities and relationships from one meta model are mapped to another

The proposed transformation rules Described in details in section 4 of paper Transformation language used: An extended version of OCL –OCL = Object Constraint Language –Designed for specifying syntax of languages –Authors wanted to stay transformation language neutral Maps data types and elements from CCA (Component Collaboration Architecture) to data types and elements in WSDL meta model (an XML Schema)

Other sections Section 1, 2 & 3: –Briefly introduces MDD, MDA, UML, EDOC, SOA, WS Section 5: –An illustrative example on how the proposed transformation rules can be used –An E-library system, modeled in EDOC, to be implemented using WS, whose WDSL files are auto- generated by the proposed rules Section 6 & 7: –Related works and Conclusions

Improvement Possibilities Specificity –Author didn’t mention what transformation engine used, and its complexity –How UML models (graphical notation) are first converted to textual notations before the transformation rules can be applied?

Improvement Possibilities Generality –OCL works (according to the paper) for this particular mapping, but was not designed as a transformation language. –UML and its derivatives have been questioned as machine-processable modeling language: Originally intended for human reading  No formal semantics

Improvement Possibilities Only generate the WDSL files –Actual implementation, if to be auto- generated, requires a different transformation –More results would be needed to make a complete solution The author mentioned that they have some work in progress Can it be combined with other reported approaches? (Commercial tools already do this for other modeling language)

Numerical Grades? Originality4/5 Technical merit3/5 Presentation4/5 Overall4/5

Conclusions The paper provides a concrete example of MDD and model transformation –Graphical meta models for EDOC and WSDL were given in the paper A set of mappings between EDOC and WSDL was provided –No vigorous testing provided, but very sensical More result will make the solution more complete and useful –How the actual implementations can be generated (using either the author’s or other’s approaches)