José Amancio M. Santos

An exploratory study to investigate the impact of conceptualization in god class detection

Context: The concept of code smells is widespread in Software Engineering. However, in spite of the many discussions and claims about them, there are few empirical studies to support or contest these ideas. In particular, the study of the human perception of what is a code smell and how to deal with it has been mostly neglected. Objective: To build empirical support to understand the effect of god classes, one of the most known code smells. In particular, this paper focuses on how conceptualization affects identification of god classes, i.e., how different people perceive the god class concept. Method: A controlled experiment that extends and builds upon another empirical study about how humans detect god classes [19]. Our study: i) deepens and details some of the research questions of the previous study, ii) introduces a new research question and, iii) when possible, compares the results of both studies. Result: Our findings show that participants have different personal criteria and preferences in choosing drivers to identify god classes. The agreement between participants is not high, which is in accordance with previous studies. Conclusion: This study contributes to expand the empirical data about the human perception of code smells. It also presents a new way to evaluate effort and distraction in experiments through the use of automatic logging of participant actions.

The problem of conceptualization in god class detection: agreement, strategies and decision drivers

BackgroundThe concept of code smells is widespread in Software Engineering. Despite the empirical studies addressing the topic, the set of context-dependent issues that impacts the human perception of what is a code smell has not been studied in depth. We call this the code smell conceptualization problem. To discuss the problem, empirical studies are necessary. In this work, we focused on conceptualization of god class. God class is a code smell characterized by classes that tend to centralize the intelligence of the system. It is one of the most studied smells in software engineering literature.MethodA controlled experiment that extends and builds upon a previous empirical study about how humans detect god classes, their decision drivers, and agreement rate. Our study delves into research questions of the previous study, adding visualization to the smell detection process, and analyzing strategies of detection.ResultOur findings show that agreement among participants is low, which corroborates previous studies. We show that this is mainly related to agreeing on what a god class is and which thresholds should be adopted, and not related to comprehension of the programs. The use of visualization did not improve the agreement among the participants. However, it did affect the choice of detection drivers.ConclusionThis study contributes to expand empirical evidences on the impact of human perception on detecting code smells. It shows that studies about the human role in smell detection are relevant and they should consider the conceptualization problem of code smells.

Investigating the Use of a Contextualized Vocabulary in the Identification of Technical Debt: A Controlled Experiment

In order to effectively manage technical debt (TD), a set of indicators has been used by automated approaches to identify TD items. However, some debt may not be directly identified using only metrics collected from the source code. CVM-TD is a model to support the identification of technical debt by considering the developer point of view when identifying TD through code comment analysis. In this paper, we analyze the use of CVM-TD with the purpose of characterizing factors that affect the accuracy of the identification of TD. We performed a controlled experiment investigating the accuracy of CVM-TD and the influence of English skills and developer experience factors. The results indicated that CVM-TD provided promising results considering the accuracy values. English reading skills have an impact on the TD detection process. We could not conclude that the experience level affects this process. Finally, we also observed that many comments suggested by CVM-TD were considered good indicators of TD. The results motivate us continuing to explore code comments in the context of TD identification process in order to improve CVM-TD.

Investigating factors that affect the human perception on god class detection: an analysis based on a family of four controlled experiments

ContextEvaluation of design problems in object oriented systems, which we call code smells, is mostly a human-based task. Several studies have investigated the impact of code smells in practice. Studies focusing on human identification of code smells have shown low agreement among developers. Unfortunately, those studies do not attempt to investigate the reasons behind this phenomenon.ObjectiveThis paper aims to investigate factors affecting human perception of code smells. Specifically, it focuses on factors affecting god class detection, one of the most known code smells.MethodThe investigation encompassed a family of four controlled experiments, covering potential factors affecting human detection of code smells. The method is incremental. In other words, each experiment produces insights to the next one. This allows the investigators to control specific factors affecting the agreement on god class detection. The factors addressed in this study are: i) developer experience, ii) developer knowledge, iii) developer training, iv) tool support for design comprehension, and v) software size.ResultOur findings show that tool support for design comprehension is the only factor that does not affect the human perception of god class. The other factors impact this perception in some way.ConclusionThe area still needs more investigation and discussion on what we call the code smell conceptualization problem, to ensure similar criteria and thresholds on human-based code smell detection.

Investigating the Identification of Technical Debt Through Code Comment Analysis

In order to effectively manage technical debt (TD), a set of indicators has been used by automated approaches to identify TD items. However, some debt items may not be directly identified using only metrics collected from the source code. CVM-TD is a model to support the identification of technical debt by considering the developer point of view when identifying TD through code comment analysis. In this paper, we investigate the use of CVM-TD with the purpose of characterizing factors that affect the accuracy of the identification of TD, and the most chosen patterns by participants as decisive to indicate TD items. We performed a controlled experiment investigating the accuracy of CVM-TD and the influence of English skills and developer experience factors. We also investigated if the contextualized vocabulary provided by CVM-TD points to candidate comments that are considered indicators of technical debt by participants. The results indicated that CVM-TD provided promising results considering the accuracy values. English reading skills have an impact on the TD detection process. We could not conclude that the experience level affects this process. We identified a list of the 20 most chosen patterns by participants as decisive to indicate TD items. The results motivate us continuing to explore code comments in the context of TD identification process in order to improve CVM-TD.

A systematic review on the code smell effect

Abstract Context: Code smell is a term commonly used to describe potential problems in the design of software. The concept is well accepted by the software engineering community. However, some studies have presented divergent findings about the usefulness of the smell concept as a tool to support software development tasks. The reasons of these divergences have not been considered because the studies are presented independently. Objective: To synthesize current knowledge related to the usefulness of the smell concept. We focused on empirical studies investigating how smells impact the software development, the code smell effect. Method: A systematic review about the smell effect is carried out. We grouped the primary studies findings in a thematic map. Result: The smell concept does not support the evaluation of quality design in practice activities of software development. There is no strong evidence correlating smells and some important software development attributes, such as effort in maintenance. Moreover, the studies point out that human agreement on smell detection is low. Conclusion: In order to improve analysis on the subject, the area needs to better outline: (i) factors affecting human evaluation of smells; and (ii) a classification of types of smells, grouping them according to relevant characteristics.

PBL Manager: Uma ferramenta de compartilhamento de problemas para auxílio à metodologia de ensino PBL

Este artigo discute a colaboracao entre estudantes na internet e a troca de conhecimento por meio desse canal de comunicacao. Propoe uma metodologia que visa potencializar as relacoes entre os usuarios de uma rede educacional situada num contexto especifico. Tal metodo tem como fundamento as teorias do contexto e a analise de redes sociais (ARS), para promover um mapeamento das redes estudadas.Refletir sobre curriculo escolar formal e comunidades de aprendizagem como metafora das TIC dinamizam os caminhos empiricos, construcoes criticas e aprofundamento da difusao do conhecimento como parte do processo de humanizacao/ tecnologizacao do homem. Oriundos de processos e movimentos contemporâneos, a consolidacao de ambientes computacionais nas escolas potencializa a construcao do conhecimento e a socializacao de praticas pedagogicas inovadoras. Esta investigacao assume as situacoes especificas curriculares, procura descobrir o que existe de mais essencial e caracteristico, partindo do conhecimento de curriculo e suas bases teoricas tradicionais, para a construcao da discussao sobre um curriculo em rede associada a instrumentalizacao das comunidades de aprendizagem.O sistema Moodle constitui-se atualmente numa das mais importantes ferramentas de apoio a cursos na Web. Apesar disto, seu modelo apresenta algumas deficiencias para uma estruturacao hierarquica e compartilhamento de materiais digitais entre disciplinas e turmas do seu ambiente virtual. Este artigo apresenta um estudo sobre a arquitetura central do Moodle, propondo a definicao de um novo nucleo, visando o aprimoramento destas caracteristicas.Estudo descritivo, qualitativo, com estudantes da 3a serie de Graduacao em Enfermagem de uma Universidade Publica de Sao Paulo, SP. Os participantes construiram Mapas Conceituais, por meio do software Cmap Tools®. Os dados foram coletados em um Grupo Focal e todos os sujeitos indicaram que o uso do software facilita e garante a organizacao, visualizacao e correlacao dos dados, porem houve dificuldades iniciais relacionadas ao manejo das ferramentas. Conclui-se, que o software Cmap Tools® favoreceu a construcao dos MC por seus recursos de formatacao, porem estrategias de orientacao deveriam ser implantadas. Como resultado, desenvolveu-se um manual para o uso do software Cmap Tool® em video Podcasting.Ha poucas iniciativas com respeito aos ambientes de virtuais para a divulgacao de materiais curriculares sobre modelagem matematica. Esses ambientes oferecem acesso as praticas pedagogicas em modelagem. Este trabalho apresenta um sistema Web para hospedar atividades de modelagem e materiais multimidia para descrever o desenvolvimento do ambiente de modelagem em sala de aula e apoiar outros professores na implementacao em suas praticas pedagogicas.A composicao e sequenciamento de Objetos de Aprendizagem sao discutidas neste trabalho a partir da representacao da estrutura conceitual de um dominio em termos das suas relacoes de dependencia. A composicao de Objetos de Aprendizagem e modelada a partir da estrutura narrativa de um discurso considerando-se os aspetos formais dos planos do conteudo e de expressao. O aspecto formal do conteudo da composicao e dado pelas pelos conceitos e seus relacionamentos e forma da expressao corresponde aos tipos de signos definidos pelo LOM. A estrutura da composicao obtida independe do tipo de midia utilizado e o modelo adequa-se as propostas de composicao adaptativas tanto do ponto de vista do meio como das disponibilidades de conexao.