1. Software Reuse Environments: An Overview Vinicius Cardoso Garcia vinicius.garcia@cesar.org.br http://www.cin.ufpe.br/~rise Advanced Software Reuse Seminars

2. RiSE Group: http://www.cin.ufpe.br/~rise 2 A brief history Tools and environments  Aid developers in producing software Earliest environments  small collections of stand-alone tools  UNIX: editors, compilers, debuggers and other utilities Data in simple standardized format Programming Support Environments (PSEs)  Collection of tools that support coding activities One or more compilers, language-sensitive editors and debuggers  Support only the SE activity and its artifact implementation and code

3. RiSE Group: http://www.cin.ufpe.br/~rise 3 A brief history (2) All SE activities are interconnected {its artifacts too!} Tools that promote the development of artifact other than code -> not integrated with other tools!!! The need for integrated support for SE activities is the genesis of Software Engineering Environments Supporting SE across the software lifecycle [Harrison et al, 2000]

4. RiSE Group: http://www.cin.ufpe.br/~rise 4 Key challenges A vast collection of tools have been prototyped or marketed  In the context of integrated environments State-of-the-practice has not advanced Each tool or environment is still highly specific to some context.  Particular language, database, OS, compiler, environment or integration platform [Harrison et al, 2000]

5. RiSE Group: http://www.cin.ufpe.br/~rise 5 Key challenges (2) Permanently Malleable Software  How to integrate and interact with other software?  How to evolve and adapt to uses? It is impossible to predict how business practices, business processes, people and technology will co- evolve over time Anticipate and pre-plan for change: design!!!  Impossible to anticipate all future needs  Traditional SD (spiral, waterfall) involve careful req. analysis and design prior to implementation [Harrison et al, 2000]

6. RiSE Group: http://www.cin.ufpe.br/~rise 6 Related works According to Meyers’ taxonomy [Meyers, 1991]:  file-based, message-passing (both local and distributed), database and canonical representation approaches [Grundy et al, 2000] identify the advantages and disadvantages of each for building tools  Supporting Wasserman’s taxonomy of types integration (data, control, presentation and process) [Wasserman, 1990]

7. RiSE Group: http://www.cin.ufpe.br/~rise 7 Software Engineering Environments File-based approaches  Unix-based software tools  However such tools generally provide limited Data, Control and Presentation integration mechanisms Message-passing approaches  Wrapped and integrated very effectively!  Data and process integration is generally not as well supported Database approaches  Very facilities: user interface, software development, but..  Difficult to extend and integrate with third-party tools Component-based SEEs  Facilitate reuse and deployment [Szyperski, 1997]

8. Software Reuse Environments

9. RiSE Group: http://www.cin.ufpe.br/~rise 9 Introduction CBSE is a continuously growing field  The environments not offer comprehensive, integrated support for the activities [Lüer, 2001]  Domain engineering and application composition Reuse -> $$$ Environments, process, certification !!!  Just a Repository ?

10. RiSE Group: http://www.cin.ufpe.br/~rise 10 CodeFinder 1 – [Henninger, 1994] Lack of a clear idea of what they need when they search for a component Query construction methods  Guide the user to formulate queries  More important than the retrieval algorithms [Frakes and Pole, 1994] 1800 Emacs Lisp components and 2900 terms

11. RiSE Group: http://www.cin.ufpe.br/~rise 11 [Thomas et al., 1997] Effects of reuse across some projects in narrow domain  Eight medium-scale Ada projects developed over a 5 years Types of reuse  Verbatim reuse: component is unchanged  Reuse with slight modification  Reuse with extensive modification Language issues in Software Reuse Organizational Support for Reuse [Basili et al., 1992]  a factory organization and project organization

12. RiSE Group: http://www.cin.ufpe.br/~rise 12 [Thomas et al., 1997] Observed clear benefits from reuse  Reduced error density  Verbatim: produce substantial improvement in error density (90%)  Reuse via slight modification: 50%  Shift in costs: fewer but more difficult errors

13. RiSE Group: http://www.cin.ufpe.br/~rise 13 [Mili et al., 1997b] Survey of existing methods of storage and retrieval in software libraries [Mili et al., 1997a] Storing and Retrieving Software Components: A Refinement Based System Effectiveness of the library's retrieval algorithm  Precision, recall and response time Source code: the key of software component  Is not practical Represent a software component with a two-field entry  The reference to the source code  A specification of the component Retrieval algorithms:  Exact retrieval  Approximate retrieval

14. RiSE Group: http://www.cin.ufpe.br/~rise 14 DARE [Frakes et al., 1998] Systematic software reuse :  quality and productivity increased – focus of software engineering to a domain-centered view  Domain engineering DARE (Domain Analysis and Reuse Environment)  Domain analyst in carrying out a well-defined domain analysis method  Extracting and recording domain information (documents and code)  Producing domains models  Repository of reusable assets for the domain

15. RiSE Group: http://www.cin.ufpe.br/~rise 15 DARE [Frakes et al., 1998]

16. RiSE Group: http://www.cin.ufpe.br/~rise 16 DARE [Frakes et al., 1998] DARE approach  Creation of generic architecture that describes architectural elements, and their relationships, for a family of systems Has been developed in a series of research prototypes  1994: developed in C on a UNIX, develop and elaborate the domain book and investigate machine-assisted graphical word and phrase extraction and clustering  1995: developed in Visual Basic 3, cut development time, the issues from first prototype is recreated Domain expert information entry form, System architecture editor. Facet table and the Generic architect editor and the generic feature table

17. RiSE Group: http://www.cin.ufpe.br/~rise 17 DARE [Frakes et al., 1998]  The third prototype is created using COTS and freeware (1998)  Currently using DARE-COTS [Frakes et al., 1997] to refine the DARE domain analysis method and investigate how the method can be supported by various commercial tools The prototypes are used to refine both the tool and the method

18. RiSE Group: http://www.cin.ufpe.br/~rise 18 Agora – [Seacord et al., 1998] Developed by the Commercial Off-the-Shelf (COTS)- Based Systems Initiative at SEI/CMU Automatically generated and indexed worldwide database of software products classified by component model Combines introspection with web search engines – reduce costs Towards a component Marketplace But...  Security, electronic commerce, and quality assurance

19. RiSE Group: http://www.cin.ufpe.br/~rise 19 Agora Query Interface

20. RiSE Group: http://www.cin.ufpe.br/~rise 20 Agora Architecture

21. RiSE Group: http://www.cin.ufpe.br/~rise 21 Odyssey [Braga et al., 1999] Support to the whole development cycle  Conceptual models to component implementation  Domain models: Use Cases and related OO models, Feature Model [Cohen, 1994]  Domain Engineering,  Method to systematize the DE,  Mediation layer: direct representation, storage and management of domain model information Using a UML notation to OO models DE process to guide the software engineer

22. RiSE Group: http://www.cin.ufpe.br/~rise 22 Odyssey [Braga et al., 1999]

23. RiSE Group: http://www.cin.ufpe.br/~rise 23 [Kwon et al., 1999] Integrated model that links the OOP paradigm with the CBD CBD Environment  Component building Design/Development for Reuse, OOP, Design Patterns and Frameworks, Re-engineering, Component description, DE, Component Certification  Component use Design/Development with Reuse, Reuse Repository, DE, Reuse Metrics Re-engineering: legacy systems in C and then generates in C++

24. RiSE Group: http://www.cin.ufpe.br/~rise 24 [Kwon et al., 1999]

25. RiSE Group: http://www.cin.ufpe.br/~rise 25 CodeFinder 2 - [Henninger, 1999] Repositories are faced with 2 problems: acquiring the knowledge and modifying the repository Retrieval method that utilizes minimal repository structure  PEEL: a tool that semi-automatically identify reusable components  CodeFinder: retrieval system CodeFinder allows component representations to be modified while users search for information  Adapts to the changing nature of the information  Incrementally improves the repository while people use it

26. RiSE Group: http://www.cin.ufpe.br/~rise 26 CodeFinder 2 - [Henninger, 1999]

27. RiSE Group: http://www.cin.ufpe.br/~rise 27 CodeFinder 2 - [Henninger, 1999]

28. RiSE Group: http://www.cin.ufpe.br/~rise 28 CLARiFi – [Thomason et al., 2000] The classification schema is a subset of a larger data model, which incorporates the roles of suplier, integrator, broker and certifier Certification  Undertaking an analysis of relevant standards in order to derive a model for component certification Two year Framework V project funded by European Commission, spanning both academia and industry  10 partners: Italy, UK, France, Germany, Denmark, Canada

29. RiSE Group: http://www.cin.ufpe.br/~rise 29 WREN – [Lüer and Rosenblum, 2001] Identifies 7 requirements for CBDEs adopted by industrial component models  However, these requirements don't cover tool integration issues Utilize the concept of requires (component run) and provides port (component performs)  Architectural view of the applications Integrated with Web Gain Visual Cafe Client of one or more component repository servers

30. RiSE Group: http://www.cin.ufpe.br/~rise 30 WREN – [Lüer and Rosenblum, 2001]

31. RiSE Group: http://www.cin.ufpe.br/~rise 31 Cadena – [Hatcliff et al., 2003] An integrated environment for building and modeling CCM systems  Defining component types using CCM IDL,  Producing CORBA stubs and skeletons in Java. Apply Cadena to avionics applications built using Boing’s Bold Stroke framework Emphasizes Java -> OpenCCM’s planned support for C++ Cadena’s methodology {8 steps}

32. RiSE Group: http://www.cin.ufpe.br/~rise 32 Cadena – [Hatcliff et al., 2003]

33. RiSE Group: http://www.cin.ufpe.br/~rise 33 [Hashizaki and Fukazawa, 2004] Analyses a collection of OO programs, acquires relationships among OO classes, and extracts reusable software components composed of some classes. The extracted components can be searched by keywords, and the result can be viewed by a web browser JavaBeans as a component architecture The process of retrieving components  the static analysis, component extraction, source indexing, and searching components

34. RiSE Group: http://www.cin.ufpe.br/~rise 34 [Hashizaki and Fukazawa, 2004]

35. RiSE Group: http://www.cin.ufpe.br/~rise 35 [Hashizaki and Fukazawa, 2004]

36. RiSE Group: http://www.cin.ufpe.br/~rise 36 [Hashizaki and Fukazawa, 2004] Search experiment

37. RiSE Group: http://www.cin.ufpe.br/~rise 37 Orion – [Lucrédio et al., 2004a] Identifies the {main requirements} for CBSEE UML modeling tool, a Java programming tool, a network tool, a middleware platform and a process model  Not originally designed to work together CBSEE requirements  Tool integration Platform integration Data integration Presentation integration Control integration Process integration

38. RiSE Group: http://www.cin.ufpe.br/~rise 38 Orion – [Lucrédio et al., 2004a]  Support for CBSE activities Domain Engineering Component-Based Development  Reusability  Referential Integrity  Software Configuration Management (SCM)  Multiple Views of Information  Security  Technology and Language Independence

39. RiSE Group: http://www.cin.ufpe.br/~rise 39 Orion – [Lucrédio et al., 2004a] Provides practical tools and solutions to perform the CBSE activities Process, called IPM, guide the software engineer to use the different tools of the environment Work in artifacts in different abstraction levels Automatic deploying the components into computers of the network

40. RiSE Group: http://www.cin.ufpe.br/~rise 40 SPARS-J - [Inoue et al. 2005] Novel graphic-representation model of a software component library (repository) Analyzing actual usage elations of the components and propagating the significance through the usage relations SPARS-J gives a higher rank to components that are used more frequently Has been used by two companies

41. RiSE Group: http://www.cin.ufpe.br/~rise 41 SPARS-J - [Inoue et al. 2005]

42. RiSE Group: http://www.cin.ufpe.br/~rise 42 SPARS-J - [Inoue et al. 2005]

43. RiSE Group: http://www.cin.ufpe.br/~rise 43 SPARS-J - [Inoue et al. 2005] Experiments  JDK 1.4.2 4.257 files, 1.290.000 LOC, 6.100 classes  SourceForge.net 140.000 Java files, create a huge database with 180.000 Java classes Case Studies in Two Companies  Daiwa Computer, 180 engineers, ISO9001:2000 and CMM3 5 applications, 1.788 components  Suntory Limited, maintenance and reuse 2.400 components, evaluate for two weeks

44. RiSE Group: http://www.cin.ufpe.br/~rise 44 MARACATU – [Garcia et al., 2005]

45. RiSE Group: http://www.cin.ufpe.br/~rise 45 MARACATU – [Garcia et al., 2005]

46. RiSE Group: http://www.cin.ufpe.br/~rise 46 Timeline – Software Reuse Environments

47. RiSE Group: http://www.cin.ufpe.br/~rise 47 Research directions And now ? Main requirements to specify, project and construct the effective Software Reuse Environment?  First step: [Lucredio et al., 2004a] requirements for CBSEEs Tool integration, Support for CBSE activities, Reusability, Referential Integrity, SCM, Multiple Views of Information, Security, Technology and Language Independence.  But, the first principal problem is to find the ideal component to reuse! Component classification?  Many algorithms for component search and retrieval

48. RiSE Group: http://www.cin.ufpe.br/~rise 48 Component search Component retrieval model [Lucrédio et a., 2004b]

49. RiSE Group: http://www.cin.ufpe.br/~rise 49 Component Search, Decade of 90… Retrieval methods:  Enumerated classification Inflexibility Problems with understanding large hierarchies  Faceted classification [Prieto-Díaz, 1991] Flexible Precise Better suited for large, continuously expanding collection Hard for users to find the right combination of terms  Free-text indexing (automatic indexing) Simple to build and retrieval Need large bodies of text to become statistically accurate

50. RiSE Group: http://www.cin.ufpe.br/~rise 50 Component Search [Frakes and Pole, 1994]  Empiricist Study Hierarchic, Faceted, Attributes and Key-words  Similar results Precision Recovery rate Maybe more important than classification!!!

51. RiSE Group: http://www.cin.ufpe.br/~rise 51 Requirements To reuse a software components, first you have to find it! All algorithms make the job But… if the system search for the users ? Active repositories! Agents make the search for you! Related components is a good idea too  ontology, web semantic, context and data mining

52. RiSE Group: http://www.cin.ufpe.br/~rise 52 Requirements Problems with repository  Costly classification  Domain analysis efforts [Henninger, 1999]  Utilizes minimal repository structure  Improves the repository (different people, different vocabulary) Centralized repositories -> repositories must be free and distributed!

53. RiSE Group: http://www.cin.ufpe.br/~rise 53 Example of an Ideal Information Retrieval Capture Text and context Semantic Analysis Query Dispatcher Intelligent Query Generation Final Results User’s Query

54. RiSE Group: http://www.cin.ufpe.br/~rise 54 So… Search Engine for software components  Passive repository x Active repository Effective in promoting reuse  Distributed (different types) repositories and Open network Security, Electronic commerce, Quality assurance  Explicit context  Automation of the reuse process… Iterative process to find the best compromise (better queries) Cluster related components together Rank the components by their popularity among software systems

55. RiSE Group: http://www.cin.ufpe.br/~rise 55 And… Metrics can help to rank the query results  Most reused components, effective reuse… But, who is guarantee the quality and security of the components?  Component Certification is one of the main requirements! Reuse not only the source code  Models, test cases, architectures, requirements, use cases… To effective Reuse, only a set of tools don’t resolve…  Reuse Process And the Market?  Components Licenses… $$$ !

56. RiSE Group: http://www.cin.ufpe.br/~rise 56 Thank you ! Questions ? Vinicius Cardoso Garcia  vinicius.garcia@cesar.org.br Eduardo Santana de Almeida  Eduardo.almeida@cesar.org.br More information available at  http://www.cin.ufpe.br/~rise

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63. RiSE Group: http://www.cin.ufpe.br/~rise 63 References [Roseman and Greenberg, 1997] M. Roseman, S. Greenberg, Simplifying Component development in an integrated groupware environment, Proceedings of the ACM UIST’97, ACM Press, 1997. [Seacord et al., 1998] R. C. Seacord, S. A. Hissan and K. C. Wallnau, Agora: A Search Engine for Software Components, IEEE Internet Computing, Vol. 2, No. 6, November/December, 1998, pp. 62-70. [Selby, 1988] R. Selby. Empirically analysing software reuse in a production environment. In: (W. Tracz, ed.), Software Reuse: Emerging Technology. IEEE Computer Society Press, 1988. [Szyperski, 1997] C.A. Szyperski, Component Software: Beyond Object-Oriented Programming, Addison-Wesley, Reading, MA, 1997. [Thomason et al., 2000] S. Thomason, P. Brereton, S. Linkman, CLARiFi: An Architecture for Component Classification and Brokerage, 2000 International Workshop on Component- Based Software Engineering (CBSE 2000), Limerick, Ireland, 2000 [Wasserman, 1990] A. Wasserman, Tool integration in software engineering environments, Software Engineering Environments: International Workshop on Environments, Springer, Berlin, 1990.