Reverse Engineering A Roadmap

Transcription

1 Reverse Engineering A Roadmap Hausi A. MŸller Jens Jahnke Dennis Smith Peggy Storey Scott Tilley Kenny Wong ICSE 2000 FoSE Track Limerick, Ireland, June 7, Outline n Brief history n Code reverse engineering n Data reverse engineering n Reverse engineering tools n Evaluating reverse engineering tools n Key research pointers n Conclusions ICSE 2000 Roadmap 2

2 The Early Days n 1980Õs There will always be old software. Laws of Software Evolution [Lehman74,78,80] Fundamental strategies for program comprehension [Brooks83, Letovsky86, Pennington87] Taxonomy for reverse engineering [Chikofsky&Cross90] Up to 90% of software evolution involves program understanding [Standish84] Long-term software evolution is as important as software constructionñin fact, probably more important today from an economic point of view ICSE 2000 Roadmap 3 An Emerging Discipline n 1990Õs Research challenges [IEEE Software90] Infrastructures and tools for the three major components of a reverse engineering system WCREÑWorking Conf. on Reverse Engineering IWPCÑInt. Workshop on Program Comprehension FEASTÑInt. Workshop on Feedback and Evolution in Software and Business Processes WES ÑInt. Workshop on Web Site Evolution Ph.D. Theses Discover abstractions in large software systems and transfer this understanding into the minds of software engineers for maintenance, evolution, and reengineering purposes. ICSE 2000 Roadmap 4

3 Recent Reverse Engineering PhD Theses n Domain retargetable reverse eng. [Tilley95] n Cognitive design elements for software exploration tools [Storey98] n Management of uncertainty and inconsistency in database reengineering [Jahnke99] n Continuous understandingñreverse Engineering Notebook [Wong99] n Integrating static and dynamic reverse engineering models [Systa2000] n Architectural component detection for program understanding [Koschke2000] ICSE 2000 Roadmap 5 Reverse Engineering Strategies n 1990Õs Reverse engineering strategies for specific program understanding and reengineering scenarios Ð Synthesizing concepts Ð Composing subsystem structures Ð Design, program, change pattern matching Ð Program slicing and dicing Ð Analysis of static and dynamic dependencies Ð Software exploration and visualization Industrial-strength reverse engineering and transformation tools ICSE 2000 Roadmap 6

4 Reverse Engineering Tasks n Information extraction Artifact gathering from many sources, knowledge organization, analysis n Information abstraction Aggregate components, relationships Synthesize abstractions Build hierarchical mental models Subject system is not altered; additional knowledge about the system is produced n Every feedback loop in life cycle models is opportunity for reverse engineering ICSE 2000 Roadmap 7 The Horseshoe Model Components Semi-automatic Abstract system Middleware Existing system Automatic New system ICSE 2000 Roadmap 8

5 Levels of Abstractions n Application Application concepts, business rules, policies n Function Logical and functional specifications, non-functional requirements n Structure Data and control flow, dependency graphs Structure and subsystem charts Architectures n Implementation ASTÕs, symbol tables, source text ICSE 2000 Roadmap 9 Synthesizing Concepts n Build multiple hierarchical mental models n Subsystems based on SE principles classes, modules, directories, cohesion, data & control flows, slices n Design and change patterns n Business and technology models n Function, system, and application architectures n Common services and infrastructure ICSE 2000 Roadmap 10

6 Data Reverse Engineering n Reverse engineering community has mostly concentrated on code reverse engineering n Data are often more important than the code n Data reverse engineering will be a key research area for the next decade n Workshop on Data Reverse Engineering ICSE 2000 Roadmap 11 Data Reverse Engineering Process n Data analysis Dealing with imperfect knowledge Customizability n Conceptual abstraction Iteration Bidirectional mapping process n Many lessons from code reverse engineering directly apply ICSE 2000 Roadmap 12

7 Evaluating Reverse Engineering Tools n The purpose of most reverse engineering tools is to increase the understanding an engineer has of the subject system n No agreed-upon definition or test of understanding n But several types of empirical studies that are appropriate for studying the benefits of reverse engineering tools ICSE 2000 Roadmap 13 The Big-Bang Reverse Engineering Problem n What can we do during evolution to ease future understanding and migration of information systems? n We know the kind of knowledge we need but it is difficult to obtain from scratch n ÒBig-bangÓ reverse engineering when the system becomes ÒcriticalÓ is high-risk n Analysis paralysis ICSE 2000 Roadmap 14

8 The Understanding Gap needed overall understanding [Wong99] useful, known overall understanding t1 t2 ICSE 2000 Roadmap 15 t Continuous Reverse Engineering n Apply program understanding continuously and incrementally during evolution of the software system n Use software reverse engineering to re-document existing software n Insert reverse engineering techniques into development [Wong99] n Symbiosis: models and code [Jackson00] ICSE 2000 Roadmap 16

9 Key Research Pointers n Investigate infrastructure, methods, and tools for continuous program understanding to support the entire evolution of a software system from the early design stages to the long-term legacy stages Reverse engineering notebook ICSE 2000 Roadmap 17 Key Research Pointers... n Instrument design architecture to ease extraction of understanding architecture n Store architecture artifacts in schema- based repository and as unstructured or Web-based text to ease searching n Allow for incomplete semantics and partial extraction of artifacts ICSE 2000 Roadmap 18

10 Key Research Pointers... n Allow user to build virtual, multiple architectures, perspectives, and views n Provide tools to compare virtual and code-centric architectures (e.g., reflection models [Murphy98]) n Make architecture extraction tools end- user programmable and extensible ICSE 2000 Roadmap 19 Key Research Pointers... n Teach reverse engineering, program understanding, and software analysis in CS, CE, and SE programs Carefully balance software analysis and software construction efforts in both research and education Restructure curricula to teach both fresh creation and evolutionary change Teach reverse engineering and program understanding methods and tools in 1st year ICSE 2000 Roadmap 20

11 Key Research Pointers... n Develop methods and technology for computer-aided data and database reverse engineering Integrate code and data reverse engineering methods and tools Leverage synergy between code and data reverse engineering communities ICSE 2000 Roadmap 21 Key Research Pointers... n Develop tools that provide better support for human reasoning in an incremental and evolutionary reverse engineering process that can be customized to different application contexts End-user programmable tools Domain retargetable reverse engineering ICSE 2000 Roadmap 22

12 Key Research Pointers É n Concentrate on the tool adoption problem by improving the usability and end-user programmability of reverse engineering tools to ease their integration into actual development processes Start with a web-based user interface Conduct user studies ICSE 2000 Roadmap 23 Conclusions n Mission statement Researchers in software design and formal methods should concentrate on software evolution rather than construction Program understanding and analysis experts should teach their methods in 1st-year n Plenty of research problems n Wonderful case studies n Exciting research!!!! ICSE 2000 Roadmap 24

13 An Invitation ICSE 2000 Roadmap 25