2. Presenter : g9102 黃培智

3. Outline  Motivation and Background  GXL Overview  Exchange Graphs  Exchange Graph Schemas  Conclusion

4. GXL Background  Tools in Software Reengineering source code extract repository abstract view visualizer: graph and diagram visualizer, code browser extractor: parser, scanner abstractor: structure recognition

5. GXL Simple Example

6. GXL History

7. Requirements of Exchange Formats  Independence application independence -language independence (C/C++, Cobol, Java, JCL, SQL, multi-language etc.) -abstraction level independence (AST, "middle level", Architecture) -aspect independence (data flow, control flow, code structure, etc.) tool independence -data structure independence (syntax trees, various types of graphs, relational databases, object oriented databases, file and directory structures)

8. Requirements of Exchange Formats  Efficiency efficiency in time efficiency in space efficiency in "building tools"  Extensibility extensible for further applications (CASE tools, visualization tools, etc)  Universality used by others standardized format

9. Outline  Motivation and Background  GXL Overview  Exchange Graphs  Exchange Graph Schemas  Conclusion

10. GXL Objective  Exchanged Data Instance data Schemas data  Mathematical Model Typed, attributed, ordered, directed graphs Expanded by hypergraphs and hierarchical graphs  Notation eXtensible Markup Language (XML) Unified Modeling Language (UML)

11. GXL Graph Model typed graphs attributed graphs directed graphs ordered graphs hierarchical graphs hyper- graphs

12. GXL Document Type Definition (1.0)

13. Outline  Motivation and Background  GXL Overview  Exchange Graphs  Exchange Graph Schemas  Conclusion

14. Supported Graph Type  Typed Graphs  Attributed Graphs  Directed Graphs  Undirected Graphs  Ordered Graphs  Hypergraphs  Hierarchical Graphs  …..

15. Directed Graphs

16. Directed Typed Graphs

17. Typed, Attributed, Directed Graphs

18. Typed, Attributed, Directed, Ordered Graphs

19. Hypergraphs.gxl#Us.gxl#V <relend target="v" role="theV"s.gxl#Ws.gxl#R direction="in"/> <relend target="w" role="theW" direction="out"/> <relend target="u" role="theFirstU" direction="out" endorder="1"/> <relend target="u" role="theSecondU" direction="out" endorder="2"/>

20. Hierarchical Graphs  Nodes, edges, and hyperedges contain further graphs

21. Outline  Motivation and Background  GXL Overview  Exchange Graphs  Exchange Graph Schemas  Conclusion

22. Exchange Schemas with GXL  Graph Schema Definition with UML Class Diagrams  Representing UML Class Diagrams by Graphs (Schema Graphs)  Exchanging Schemas Graphs by GXL Documents

23. Exchange Schemas with GXL Graph Class (UML class diagram) Var file : string line : int refs Proc Var file="main.c" line = 27 line = 42 e : refs Graph p : Proc v :

24. GXL Schema Representation UML class diagram Var file:string line : int Proc refs Proc:NodeClass name="Proc" a1:Attribute name="file" s : String refs: EdgeClass name="refs" var:NodeClass name="Var" i : Integer a2:Attribute name="line" comesFrom goesTo has Attribute has Domain has Attribute has Attribute has Domain Schema Graph

25. GXL Schema Representation Proc refs Var...

26. Conclusion  GXL : uniform language for Exchanging graphs Exchanging graph schemas  GXL : ratified as standard exchange format Software Reengineering community (Dagstuhl, January 26. 2001) Usage within GTXL Graph Transformation Exchange Language systems (APPLIGRAPH Subgroup Meeting, Bremen, March, 1-2. 2001)