Search based software engineering: Trends, techniques and applications

© ACM, 2012. This is the author's version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution. The definitive version is available from the link below.In the past five years there has been a dramatic increase in work on Search-Based Software Engineering (SBSE), an approach to Software Engineering (SE) in which Search-Based Optimization (SBO) algorithms are used to address problems in SE. SBSE has been applied to problems throughout the SE lifecycle, from requirements and project planning to maintenance and reengineering. The approach is attractive because it offers a suite of adaptive automated and semiautomated solutions in situations typified by large complex problem spaces with multiple competing and conflicting objectives. This article provides a review and classification of literature on SBSE. The work identifies research trends and relationships between the techniques applied and the applications to which they have been applied and highlights gaps in the literature and avenues for further research.EPSRC and E

A large-scale empirical exploration on refactoring activities in open source software projects

Refactoring is a well-established practice that aims at improving the internal structure of a software system without changing its external behavior. Existing literature provides evidence of how and why developers perform refactoring in practice. In this paper, we continue on this line of research by performing a large-scale empirical analysis of refactoring practices in 200 open source systems. Specifically, we analyze the change history of these systems at commit level to investigate: (i) whether developers perform refactoring operations and, if so, which are more diffused and (ii) when refactoring operations are applied, and (iii) which are the main developer-oriented factors leading to refactoring. Based on our results, future research can focus on enabling automatic support for less frequent refactorings and on recommending refactorings based on the developer's workload, project's maturity and developer's commitment to the project

A review of software change impact analysis

Change impact analysis is required for constantly evolving systems to support the comprehension, implementation, and evaluation of changes. A lot of research effort has been spent on this subject over the last twenty years, and many approaches were published likewise. However, there has not been an extensive attempt made to summarize and review published approaches as a base for further research in the area. Therefore, we present the results of a comprehensive investigation of software change impact analysis, which is based on a literature review and a taxonomy for impact analysis. The contribution of this review is threefold. First, approaches proposed for impact analysis are explained regarding their motivation and methodology. They are further classified according to the criteria of the taxonomy to enable the comparison and evaluation of approaches proposed in literature. We perform an evaluation of our taxonomy regarding the coverage of its classification criteria in studied literature, which is the second contribution. Last, we address and discuss yet unsolved problems, research areas, and challenges of impact analysis, which were discovered by our review to illustrate possible directions for further research

Supporting the grow-and-prune model for evolving software product lines

207 p.Software Product Lines (SPLs) aim at supporting the development of a whole family of software products through a systematic reuse of shared assets. To this end, SPL development is separated into two interrelated processes: (1) domain engineering (DE), where the scope and variability of the system is defined and reusable core-assets are developed; and (2) application engineering (AE), where products are derived by selecting core assets and resolving variability. Evolution in SPLs is considered to be more challenging than in traditional systems, as both core-assets and products need to co-evolve. The so-called grow-and-prune model has proven great flexibility to incrementally evolve an SPL by letting the products grow, and later prune the product functionalities deemed useful by refactoring and merging them back to the reusable SPL core-asset base. This Thesis aims at supporting the grow-and-prune model as for initiating and enacting the pruning. Initiating the pruning requires SPL engineers to conduct customization analysis, i.e. analyzing how products have changed the core-assets. Customization analysis aims at identifying interesting product customizations to be ported to the core-asset base. However, existing tools do not fulfill engineers needs to conduct this practice. To address this issue, this Thesis elaborates on the SPL engineers' needs when conducting customization analysis, and proposes a data-warehouse approach to help SPL engineers on the analysis. Once the interesting customizations have been identified, the pruning needs to be enacted. This means that product code needs to be ported to the core-asset realm, while products are upgraded with newer functionalities and bug-fixes available in newer core-asset releases. Herein, synchronizing both parties through sync paths is required. However, the state of-the-art tools are not tailored to SPL sync paths, and this hinders synchronizing core-assets and products. To address this issue, this Thesis proposes to leverage existing Version Control Systems (i.e. git/Github) to provide sync operations as first-class construct

Definition of Descriptive and Diagnostic Measurements for Model Fragment Retrieval

Tesis por compendio[ES] Hoy en día, el software existe en casi todo. Las empresas a menudo desarrollan y mantienen colecciones de sistemas de software personalizados que comparten algunas características entre ellos, pero que también tienen otras características particulares. Conforme el número de características y el número de variantes de un producto crece, el mantenimiento del software se vuelve cada vez más complejo. Para hacer frente a esta situación la Comunidad de Ingeniería del Software basada en Modelos está abordando una actividad clave: la Localización de Fragmentos de Modelo. Esta actividad consiste en la identificación de elementos del modelo que son relevantes para un requisito, una característica o un bug. Durante los últimos años se han propuesto muchos enfoques para abordar la identificación de los elementos del modelo que corresponden a una funcionalidad en particular. Sin embargo, existe una carencia a la hora de cómo se reportan las medidas del espacio de búsqueda, así como las medidas de la solución a encontrar. El objetivo de nuestra tesis radica en proporcionar a la comunidad dedicada a la actividad de localización de fragmentos de modelo una serie de medidas (tamaño, volumen, densidad, multiplicidad y dispersión) para reportar los problemas de localización de fragmentos de modelo. El uso de estas novedosas medidas ayuda a los investigadores durante la creación de nuevos enfoques, así como la mejora de aquellos enfoques ya existentes. Mediante el uso de dos casos de estudio reales e industriales, esta tesis pone en valor la importancia de estas medidas para comparar resultados de diferentes enfoques de una manera precisa. Los resultados de este trabajo han sido redactados y publicados en foros, conferencias y revistas especializadas en los temas y contexto de la investigación. Esta tesis se presenta como un compendio de artículos acorde a la regulación de la Universitat Politècnica de València. Este documento de tesis presenta los temas, el contexto y los objetivos de la investigación. Presenta las publicaciones académicas que se han publicado como resultado del trabajo y luego analiza los resultados de la investigación.[CA] Hui en dia, el programari existix en quasi tot. Les empreses sovint desenrotllen i mantenen col·leccions de sistemes de programari personalitzats que compartixen algunes característiques entre ells, però que també tenen altres característiques particulars. Conforme el nombre de característiques i el nombre de variants d'un producte creix, el manteniment del programari es torna cada vegada més complex. Per a fer front a esta situació la Comunitat d'Enginyeria del Programari basada en Models està abordant una activitat clau: la Localització de Fragments de Model. Esta activitat consistix en la identificació d'elements del model que són rellevants per a un requisit, una característica o un bug. Durant els últims anys s'han proposat molts enfocaments per a abordar la identificació dels elements del model que corresponen a una funcionalitat en particular. No obstant això, hi ha una carència a l'hora de com es reporten les mesures de l'espai de busca, així com les mesures de la solució a trobar. L'objectiu de la nostra tesi radica a proporcionar a la comunitat dedicada a l'activitat de localització de fragments de model una sèrie de mesures (grandària, volum, densitat, multiplicitat i dispersió) per a reportar els problemes de localització de fragments de model. L'ús d'estes noves mesures ajuda als investigadors durant la creació de nous enfocaments, així com la millora d'aquells enfocaments ja existents. Per mitjà de l'ús de dos casos d'estudi reals i industrials, esta tesi posa en valor la importància d'estes mesures per a comparar resultats de diferents enfocaments d'una manera precisa. Els resultats d'este treball han sigut redactats i publicats en fòrums, conferències i revistes especialitzades en els temes i context de la investigació. Esta tesi es presenta com un compendi d'articles d'acord amb la regulació de la Universitat Politècnica de València. Este document de tesi presenta els temes, el context i els objectius de la investigació. Presenta les publicacions acadèmiques que s'han publicat com resultat del treball i després analitza els resultats de la investigació.[EN] Nowadays, software exists in almost everything. Companies often develop and maintain a collection of custom-tailored software systems that share some common features but also support customer-specific ones. As the number of features and the number of product variants grows, software maintenance is becoming more and more complex. To keep pace with this situation, Model-Based Software Engineering Community is addressing a key-activity: Model Fragment Location (MFL). MFL aims at identifying model elements that are relevant to a requirement, feature, or bug. Many MFL approaches have been introduced in the last few years to address the identification of the model elements that correspond to a specific functionality. However, there is a lack of detail when the measurements about the search space (models) and the measurements about the solution to be found (model fragment) are reported. The goal of this thesis is to provide insights to MFL Research Community of how to improve the report of location problems. We propose using five measurements (size, volume, density, multiplicity, and dispersion) to report the location problems during MFL. The usage of these novel measurements support researchers during the creation of new MFL approaches and during the improvement of those existing ones. Using two different case studies, both real and industrial, we emphasize the importance of these measurements in order to compare results in a deeply way. The results of the research have been redacted and published in forums, conferences, and journals specialized in the topics and context of the research. This thesis is presented as compendium of articles according the regulations in Universitat Politècnica de València. This thesis document introduces the topics, context, and objectives of the research, presents the academic publications that have been published as a result of the work, and then discusses the outcomes of the investigation.Ballarin Naya, M. (2021). Definition of Descriptive and Diagnostic Measurements for Model Fragment Retrieval [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/171604TESISCompendi

UML Consistency Rules:a Case Study with Open-Source UML Models

UML models are standard artifacts used by software engineers for designing software. As software is designed, different UML diagram types (e.g., class diagrams and sequence diagrams) are produced by software designers. Since the various UML diagram types describe different aspects of a software system, they are not independent but strongly depend on each other, hence they must be consistent. Inconsistencies cause faults in the final software systems. It is, therefore, paramount that they get detected, analyzed, and fixed. Consistency rules are a useful tool proposed in the literature to detect inconsistencies. They categorize constraints that help in identifying inconsistencies when violated. This case study aims at collecting and analyzing UML models with OCL consistency rules proposed in the literature and at promoting the development of a reference benchmark that can be reused by the (FM-)research community. We collected 33 UML consistency rules and 206 different UML diagrams contained in 34 open-source UML models presented in the literature. We propose an FM-based encoding of the consistency rules in OCL. This encoding allows analyzing whether the consistency rules are satisfied or violated within the 34 UML models. To assess the proposed benchmark, we analyzed how the UML models, consistency rules, diagram types contained in the benchmark help in assessing the consistency of UML models, and the consistency of diagrams across the different software development phases. Our results show that the considered UML models and consistency rules allowed identifying 2731 inconsistencies and that those inconsistencies refer to different software development phases. We concluded that the considered UML models and consistency rules could be considered as an initial benchmark that can be further extended by the research community