Das SCCH ist eine Initiative der Das SCCH befindet sich im Empirical Evaluation of Strategies to Detect Logical Change Dependencies SOFSEM 2010 Günter Pirkblauer

2/13© Software Competence Center Hagenberg GmbH Overview Introduction Motivation of Research Evaluation Approach Strategies Results Discussion

3/13© Software Competence Center Hagenberg GmbH Introduction Software Maintenance Life cycle of software systems comprises not only the analysis-, design- and development phases, but also the maintenance. Exceed 75% of the all over development costs (up to 95%) In Software Maintenance, all is about Changes New requirements  changes in the system Changes increase the complexity Changes often lead to new errors  need to perform Change Impact Analysis

4/13© Software Competence Center Hagenberg GmbH Introduction Change Impact Analysis „… identifiying the potential consequence of a change, or estimated what needs to be modified to accomplish a change …“ [ArnoldBohner1996] … is more a discipline than an approach … needs the identification of artifacts and dependencies General Approaches/Principles: Software Traceability and Dependency Analysis (in consequence: Software Evolution Analysis, Change Coupling Analysis, …)

5/13© Software Competence Center Hagenberg GmbH Introduction Software Traceability Dependency Analysis (static/dynamic) Change Coupling Analysis Approaches

6/13© Software Competence Center Hagenberg GmbH Introduction Change Coupling Analysis … try to detect logical change dependencies of artifacts based on co-changes in the versioning system … are relevant for change impact analysis, because they enlarge physical dependencies (e.g. static code analysis)  analysis of check-ins of developers  especiallly transactions, time, comments, users, … … need strategies (algorithm, patterns) to detect change couplings

7/13© Software Competence Center Hagenberg GmbH 7 Introduction: CIA-Framework Strategies!

8/13© Software Competence Center Hagenberg GmbH Introduction: The CIA-Framework Change Impact Analysis … it looks like:

9/13© Software Competence Center Hagenberg GmbH Motivation of Research Strategies are based on typical project scenarios Analysis of project scenarios (learning, how developers do their job) Identification of strategies Literature Analysis Implementing strategies in a framework Empirical evaluation of strategies

10/13© Software Competence Center Hagenberg GmbH Evaluation Approach Evaluation of 2 projects Determine the quantities of dependencies Analyzing the „contribution“ of each strategy Analyzing overlappings of results

11/13© Software Competence Center Hagenberg GmbH Study Approach 2 Projects

12/13© Software Competence Center Hagenberg GmbH Strategies Transaction-based Strategy Comment-based Strategy Change-ID-based-Strategy Change-Hierarchy-based Strategy

13/13© Software Competence Center Hagenberg GmbH Strategies Transaction-based Strategy

14/13© Software Competence Center Hagenberg GmbH Strategies Comment-based Strategy

15/13© Software Competence Center Hagenberg GmbH Strategies Change-ID-based-Strategy

16/13© Software Competence Center Hagenberg GmbH Strategies Change-Hierarchy-based Strategy  Data from outside the Versioning-System Database

17/13© Software Competence Center Hagenberg GmbH Results Project 1

18/13© Software Competence Center Hagenberg GmbH Results Project 2

19/13© Software Competence Center Hagenberg GmbH Discussion Distribution of Dependencies

20/13© Software Competence Center Hagenberg GmbH Discussion Unique and Overlapping Dependency Results Transaction-based Dependencies are completely covered by other strategies (mostly Comment-based Dep.) Change-hierarchy-based Dep. have overlappings with Transaction-based- and ChangeID-based Dependencies Majority of Change-hierarchy-based dependencies are unique

21/13© Software Competence Center Hagenberg GmbH Discussion Ratio of Check-ins with Change-ID and Change-ID based Dependencies Coherence between Change-IDs and Change-ID based Dependencies (Project 1: 46%/55,6%, Project 2: 7%/3,5%) Change-ID based dependencies are high reliable Benefit of integrated IDEs like Eclipse (programming, bug- and change-tracking, versioning system) for Change Impact Analysis

22/13© Software Competence Center Hagenberg GmbH Thank you!