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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Eyes Of Darwin : une fenêtre ouverte sur l'évolution du logiciel

Tanteri, Julien 12 1900 (has links)
No description available.
112

Compreensão de mudanças estruturais no código fonte usando análise dinâmica e estática / Understanding structural changes in source code using dynamic and static analysis

Silva, Janio Rosa 17 December 2015 (has links)
A compreensão de sistemas é fundamental para a atividade de manutenção. Durante a manutenção e evolução dos sistemas, mudanças contínuas podem degradar o projeto modular do sistema, aumentando sua complexidade. Consequentemente, as empresas gastam muito tempo e recursos financeiros na compreensão e manutenção dos sistemas. Portanto, entender como o sistema evolui é uma etapa importante para o bom planejamento, desenvolvimento e gerenciamento de mudanças. Os desenvolvedores geralmente precisam entender rapidamente mudanças recentes antes de implementar novas mudanças. Mesmo que já existam abordagens para a compreensão, elas ainda são limitadas para detectar componentes diferentes com tarefas similares, para localizar tarefas no código fonte e para medir o impacto de uma determinada mudança nas funcionalidades do sistema. Neste trabalho, é proposto um mecanismo para localizar impactos causados por uma mudança no projeto e quais mudanças estruturais ocorreram em um sistema de uma versão para outra. Dada uma funcionalidade específica, o objetivo é localizar mudanças estruturais e mudanças de relacionamento entre componentes entre duas versões. Cada mudança estrutural detectada na primeira etapa é checada no código fonte para ambas as versões. Depois, as mudanças são classificadas em cinco padrões: i) movimentação de classe; ii) movimentação de método; iii) adição de método; iv) remoção de método; e v) mudança no modificador de acesso (os três últimos que representam mudanças de interface nas classes). A abordagem proposta é avaliada com três sistemas de código aberto com o objetivo de validar a metodologia: jFreeChart, Tomcat e JHotDraw. Os resultados revelam mudanças estruturais como movimentação de método, movimentação de classe e mudança de relacionamento de pacotes. Além disso, também é feito um levantamento de mudanças estruturais que afetam múltiplas funcionalidades, o que é chamado de avaliação de impacto de mudanças; análises sobre mudanças de relacionamento de pacotes no jFreeChart validado em termos de precisão e recall. Os resultados mostram que movimentações em métodos, em média, aparecem em 28,4% dos casos. Existem classes que afetam muitas funcionalidades, logo o desenvolvedor terá noção de quais funcionalidades serão afetadas com tais mudanças. As mudanças no jFreeChart mostram que a abordagem detecta os padrões de alterações em pacotes a uma precisão de 100% e revocação de 83%. Ao detectar uma mudança considerável na relação de pacotes entre o jFreeChart versões 0.7.0 e 0.9.5, foi constatado que os novos pacotes possuem um menor acoplamento, conforme a métrica efferent coupling, podendo indicar uma melhor modularização. Portanto detectar estas mudanças nos pacotes pode ajudar o desenvolvedor a explicar a coesão, acoplamento e a modularidade do sistema em termo de pacotes. Um dos resultados importantes da abordagem, a avaliação de impacto de mudanças, permite ao desenvolvedor avaliar o passado do sistema, e prever o impacto e abrangência de mudanças futuras em classes e funcionalidades. / Software system comprehension is a key maintenance activity. During the software maintenance and evolution, continuous changes may degrade the modular design overtime, thus, increasing its complexity. Consequently, companies spend a lot of time and resources trying to understand and implement changes on software. Therefore, understanding how system changes evolve is an important step towards future development planing and management. Developers usually need to rapidly understand recent changes before implementing a new feature. Despite of several approaches to improve software comprehension, they are still limited to different components with similar roles, to locate features in the source code and to measure the impact of an specific change in other features. In this work, we present an approach centered on dynamic and static analysis to reduce program comprehension effort. More specifically, we propose a mechanism to locate what structural changes have occurred in a program from one version to another. Given one specific functionality, we locate structural changes and component relationship changes between two versions. Each structural change previously detected in the first step, is then verified by a next step of static analysis to confirm if the method in the trace really exists in only one version or both versions. The candidate changes are classified in five patterns by parsing the source code of both analyzed version: i) Move Class, ii) Move Method, iii) Add Method, iv) Remove Method, and v) Access Modifier Change (where they represent Class Interface Change). We evaluated our approach with three open source-software systems: jFreeChart, Tomcat, and JHotDraw. Our results reveals structural changes such as, move method, move class, and package relationship changes. In this study, we further investigate the impact of structural changes over multiple functionalities. We also evaluated the package relationship change found in jFreeChart using precision and recall. The results show that the pattern Move Method dominates, in average, appearing in 28,4% of the changes. Also, there are changes in classes that affect many funcionalities. Also the results show that in jFreeChart there were changes in packages detected with a precision of 100% and a recall of 83%. After the approach detected many changes between versions 0.7.0 and 0.9.5 of jFreeChart, further analysis showed that the new package structure has less coupling measures, according to the Efferent Coupling metric. That can mean the package structure has a better modular structure. Then detecting those changes in the package structure can be valuable to the developer evaluate the cohesion, coupling and package modular structure. One of the results presented by this approach, the impact analysis, allow the developer, by evaluating the past of the system, foresee the impact and coverage of future changes that will be made in the system. / Dissertação (Mestrado)
113

Translation and Transformation of Low Level Programs / Prevođenje i transformisanje programa niskog nivoa

Pracner Doni 17 April 2019 (has links)
<p>This thesis presents an approach for working with low level source code that enables automatic restructuring and raising the abstraction level of the programs. This makes it easier to understand the logic of the program, which in turn reduces the development time.The process in this thesis was designed to be flexible and consists of several independent tools. This makes the process easy to adapt as needed, while at the same time the developed tools can be used for other processes. There are usually two basic steps. First is the translation to WSL language, which has a great number of semantic preserving program transformations. The second step are the transformations of the translated WSL. Two tools were developed for translation: one that works with a subset of x86 assembly, and another that works with MicroJava bytecode. The result of the translation is a low level program in WSL.The primary goal of this thesis was to fully automate the selection of the transformations. This enables users with no domain&nbsp; knowledge to efficiently use this process as needed. At the same time, the flexibility of the process enables experienced users to adapt it as needed or integrate it into other processes. The automation was achieved with a <em>hill climbing </em>algorithm.Experiments that were run on several types of input programs showed that the results can be excellent. The fitness function used was a built-in metric that gives the &ldquo;weight&rdquo; of structures in a program. On input samples that had original high level source codes, the end result metrics of the translated and transformed programs were comparable. On some samples the result was even better than the originals, on some others they were somewhat more complex. When comparing with low level original source code, the end results was always significantly improved.</p> / <p>U okviru ove teze se predstavlja pristup radu sa programima niskog nivoa koji omogućava automatsko restrukturiranje i podizanje na vi&scaron;e nivoe. Samim tim postaje mnogo lak&scaron;e razumeti logiku programa &scaron;to smanjuje vreme razvoja.Proces je dizajniran tako da bude fleksibilan i sastoji se od vi&scaron;e nezavisnih alata. Samim tim je lako menjati proces po potrebi, ali i upotrebiti razvijene alate u drugim procesima. Tipično se mogu razlikovati dva glavna koraka. Prvi je prevođenje u jezik WSL,za koji postoji veliki broj transformacija programa koje očuvavaju semantiku. Drugi su transformacije u samom WSL-u. Za potrebe prevođenja su razvijena dva alata, jedan koji radi sa podskupom x86 asemblera i drugi koji radi sa MikroJava bajtk&ocirc;dom. Rezultat prevođenja je program niskog nivoa u WSL jeziku.Primarni cilj ovog istraživanja je bila potpuna automatizacija odabira transformacija, tako da i korisnici bez iskustva u radu sa sistemom mogu efikasno da primene ovaj proces za svoje potrebe. Sa druge strane zbog fleksibilnosti procesa, iskusni korisnici mogu lakoda ga pro&scaron;ire ili da ga integri&scaron;u u neki drugi već postojeći&nbsp;&nbsp; proces.Automatizacija je&nbsp; postignuta pretraživanjem usponom (eng. hill climbing).Eksperimenti vr&scaron;eni na nekoliko tipova ulaznih programa niskog nivoa su pokazali da rezultati mogu biti&nbsp; izuzetni. Za funkciju pogodnosti je kori&scaron;ćena ugrađena metrika koja daje &ldquo;težinu&rdquo; struktura u programu. Kod ulaza za koje je originalni izvorni k&ocirc;d bio dostupan, krajnje metrike najboljih varijanti prevedenih i transformisanih programa su bile na sličnom nivou. Neki primeri su bolji od originala, dok su drugi bili ne&scaron;to kompleksniji. Rezultati su uvek pokazivali značajna unapređenja u odnosu na originalni k&ocirc;d niskog nivoa.</p>
114

[pt] IDENTIFICANDO CANDIDATOS A MICROSSERVIÇOS EM CÓDIGO LEGADO / [en] IDENTIFYING MICROSERVICES CANDIDATES IN LEGACY CODE

10 December 2020 (has links)
[pt] Microsserviços é uma técnica industrial para promover melhor escalabilidade e manutenibilidade de pequenos e autônomos serviços. Estudos prévios sugerem que a arquitetura de microsserviços vem sendo amplamente usada para reduzir limitações encontradas em sistemas monolíticos legados tais como melhoria de inovação, uso de diferentes tecnologias, entre outras. O processo de migração para a arquitetura de microsserviços não é trivial. Este é particularmente o caso da tarefa de identificar candidatos a microsserviço e o código fonte associado com cada candidato que é dispendiosa e propensa a erro. Consequentemente, abordagens automatizadas têm sido propostas para reduzir o esforço relacionado a essa atividade. Essas abordagens comumente adotam um ou dois critérios para suportar a identificação de microsserviços com base no sistema monolítico legado. Contudo, existe uma falta de compreensão da utilidade desses critérios adotados na prática. Além disso, há limitado conhecimento em quais são os critérios que profissionais consideram relevantes. Levando em consideração esses limitantes existentes, nós conduzimos um survey e entrevista para melhor compreender a utilidade de critérios relatados em estudos empíricos (e.g, estudos de caso e relatos) do ponto de vista dos profissionais. Os resultados do survey e da entrevista mostram que as abordagens automatizadas e ferramentas existentes não são totalmente alinhadas com necessidades práticas. Para atender às necessidades deles, este trabalho define uma abordagem automatizada chamada toMicroservices. A abordagem baseia-se em uma combinação de análise estática e dinâmica do código legado. A abordagem visa indicar os candidatos a microsserviço e a fonte correspondente extraído do sistema legado. toMicroservices faz uso da engenharia de software baseada em busca para otimizar e balancear os cinco critérios comumente adotados por profisionais, nomeados de modularização de funcionalidade, redução de sobrecarga de rede, reúso, acoplamento e coesão. Além disso, um estudo de caso e grupo focal foram conduzidos a posteriori para avaliar e melhorar toMicroservices. / [en] Microservices is an industrial technique to promote better scalability and maintainability of small and autonomous services. Previous studies suggested that microservice architectures have been widely used to reduce limitations found in legacy monolithic systems such as the inclusion of innovation, use of a different stack of technologies, among others. The process of migrating to a microservices architecture is far from trivial. This is particularly the case for the task of identifying candidate microservices and the source code associated with each candidate, which is recognizably time-consuming and error-prone. Thus, automated approaches have been proposed to reduce the effort related to that task. These approaches commonly adopt one or two criteria to support the identification of microservices from a legacy monolithic system. However, there is a lack of understanding on the usefulness of these criteria in practical settings. Moreover, there is limited knowledge on what are the criteria that practitioners consider relevant. Taking into account these existing limitations, we conducted a survey and interviews to better understand the usefulness of criteria reported in empirical studies (e.g, case studies and reports) from the point of view of practitioners. The results of the survey and interviews revealed that existing automated approaches and tools are far from being aligned with practical needs. To fulfill these needs, this work defines a automated approach named toMicroservices. The approach relies on a combination of static and dynamic analysis of the legacy code. The approach aims at indicating the microservice candidates and the corresponding source extracted from the legacy system. toMicroservices makes use of search-based software engineering (SBSE) to optimize and balance the five criteria commonly adopted by practitioners, namely feature modularization, network overhead reduction, reuse, coupling and cohesion. Additionally, an industrial case study and a focus group were conducted a posteriori to support the evaluation and improvements of toMicroservices.
115

Cliff Walls: Threats to Validity in Empirical Studies of Open Source Forges

Pratt, Landon James 27 February 2013 (has links) (PDF)
Artifact-based research provides a mechanism whereby researchers may study the creation of software yet avoid many of the difficulties of direct observation and experimentation. Open source software forges are of great value to the software researcher, because they expose many of the artifacts of software development. However, many challenges affect the quality of artifact-based studies, especially those studies examining software evolution. This thesis addresses one of these threats: the presence of very large commits, which we refer to as "Cliff Walls." Cliff walls are a threat to studies of software evolution because they do not appear to represent incremental development. In this thesis we demonstrate the existence of cliff walls in open source software projects and discuss the threats they present. We also seek to identify key causes of these monolithic commits, and begin to explore ways that researchers can mitigate the threats of cliff walls.
116

Supporting Source Code Comprehension During Software Evolution and Maintenance

Alhindawi, Nouh Talal 30 July 2013 (has links)
No description available.
117

Quantitative Modeling and Verification of Evolving Software

Getir Yaman, Sinem 15 September 2021 (has links)
Mit der steigenden Nachfrage nach Innovationen spielt Software in verschiedenenWirtschaftsbereichen eine wichtige Rolle, wie z.B. in der Automobilindustrie, bei intelligenten Systemen als auch bei Kommunikationssystemen. Daher ist die Qualität für die Softwareentwicklung von großer Bedeutung. Allerdings ändern sich die probabilistische Modelle (die Qualitätsbewertungsmodelle) angesichts der dynamischen Natur moderner Softwaresysteme. Dies führt dazu, dass ihre Übergangswahrscheinlichkeiten im Laufe der Zeit schwanken, welches zu erheblichen Problemen führt. Dahingehend werden probabilistische Modelle im Hinblick auf ihre Laufzeit kontinuierlich aktualisiert. Eine fortdauernde Neubewertung komplexer Wahrscheinlichkeitsmodelle ist jedoch teuer. In letzter Zeit haben sich inkrementelle Ansätze als vielversprechend für die Verifikation von adaptiven Systemen erwiesen. Trotzdem wurden bei der Bewertung struktureller Änderungen im Modell noch keine wesentlichen Verbesserungen erzielt. Wahrscheinlichkeitssysteme werden als Automaten modelliert, wie bei Markov-Modellen. Solche Modelle können in Matrixform dargestellt werden, um die Gleichungen basierend auf Zuständen und Übergangswahrscheinlichkeiten zu lösen. Laufzeitmodelle wie Matrizen sind nicht signifikant, um die Auswirkungen von Modellveränderungen erkennen zu können. In dieser Arbeit wird ein Framework unter Verwendung stochastischer Bäume mit regulären Ausdrücken entwickelt, welches modular aufgebaut ist und eine aktionshaltige sowie probabilistische Logik im Kontext der Modellprüfung aufweist. Ein solches modulares Framework ermöglicht dem Menschen die Entwicklung der Änderungsoperationen für die inkrementelle Berechnung lokaler Änderungen, die im Modell auftreten können. Darüber hinaus werden probabilistische Änderungsmuster beschrieben, um eine effiziente inkrementelle Verifizierung, unter Verwendung von Bäumen mit regulären Ausdrücken, anwenden zu können. Durch die Bewertung der Ergebnisse wird der Vorgang abgeschlossen. / Software plays an innovative role in many different domains, such as car industry, autonomous and smart systems, and communication. Hence, the quality of the software is of utmost importance and needs to be properly addressed during software evolution. Several approaches have been developed to evaluate systems’ quality attributes, such as reliability, safety, and performance of software. Due to the dynamic nature of modern software systems, probabilistic models representing the quality of the software and their transition probabilities change over time and fluctuate, leading to a significant problem that needs to be solved to obtain correct evaluation results of quantitative properties. Probabilistic models need to be continually updated at run-time to solve this issue. However, continuous re-evaluation of complex probabilistic models is expensive. Recently, incremental approaches have been found to be promising for the verification of evolving and self-adaptive systems. Nevertheless, substantial improvements have not yet been achieved for evaluating structural changes in the model. Probabilistic systems are usually represented in a matrix form to solve the equations based on states and transition probabilities. On the other side, evolutionary changes can create various effects on theese models and force them to re-verify the whole system. Run-time models, such as matrices or graph representations, lack the expressiveness to identify the change effect on the model. In this thesis, we develop a framework using stochastic regular expression trees, which are modular, with action-based probabilistic logic in the model checking context. Such a modular framework enables us to develop change operations for the incremental computation of local changes that can occur in the model. Furthermore, we describe probabilistic change patterns to apply efficient incremental quantitative verification using stochastic regular expression trees and evaluate our results.
118

Modelling software quality : a multidimensional approach

Vaucher, Stéphane 11 1900 (has links)
Les sociétés modernes dépendent de plus en plus sur les systèmes informatiques et ainsi, il y a de plus en plus de pression sur les équipes de développement pour produire des logiciels de bonne qualité. Plusieurs compagnies utilisent des modèles de qualité, des suites de programmes qui analysent et évaluent la qualité d'autres programmes, mais la construction de modèles de qualité est difficile parce qu'il existe plusieurs questions qui n'ont pas été répondues dans la littérature. Nous avons étudié les pratiques de modélisation de la qualité auprès d'une grande entreprise et avons identifié les trois dimensions où une recherche additionnelle est désirable : Le support de la subjectivité de la qualité, les techniques pour faire le suivi de la qualité lors de l'évolution des logiciels, et la composition de la qualité entre différents niveaux d'abstraction. Concernant la subjectivité, nous avons proposé l'utilisation de modèles bayésiens parce qu'ils sont capables de traiter des données ambiguës. Nous avons appliqué nos modèles au problème de la détection des défauts de conception. Dans une étude de deux logiciels libres, nous avons trouvé que notre approche est supérieure aux techniques décrites dans l'état de l'art, qui sont basées sur des règles. Pour supporter l'évolution des logiciels, nous avons considéré que les scores produits par un modèle de qualité sont des signaux qui peuvent être analysés en utilisant des techniques d'exploration de données pour identifier des patrons d'évolution de la qualité. Nous avons étudié comment les défauts de conception apparaissent et disparaissent des logiciels. Un logiciel est typiquement conçu comme une hiérarchie de composants, mais les modèles de qualité ne tiennent pas compte de cette organisation. Dans la dernière partie de la dissertation, nous présentons un modèle de qualité à deux niveaux. Ces modèles ont trois parties: un modèle au niveau du composant, un modèle qui évalue l'importance de chacun des composants, et un autre qui évalue la qualité d'un composé en combinant la qualité de ses composants. L'approche a été testée sur la prédiction de classes à fort changement à partir de la qualité des méthodes. Nous avons trouvé que nos modèles à deux niveaux permettent une meilleure identification des classes à fort changement. Pour terminer, nous avons appliqué nos modèles à deux niveaux pour l'évaluation de la navigabilité des sites web à partir de la qualité des pages. Nos modèles étaient capables de distinguer entre des sites de très bonne qualité et des sites choisis aléatoirement. Au cours de la dissertation, nous présentons non seulement des problèmes théoriques et leurs solutions, mais nous avons également mené des expériences pour démontrer les avantages et les limitations de nos solutions. Nos résultats indiquent qu'on peut espérer améliorer l'état de l'art dans les trois dimensions présentées. En particulier, notre travail sur la composition de la qualité et la modélisation de l'importance est le premier à cibler ce problème. Nous croyons que nos modèles à deux niveaux sont un point de départ intéressant pour des travaux de recherche plus approfondis. / As society becomes ever more dependent on computer systems, there is more and more pressure on development teams to produce high-quality software. Many companies therefore rely on quality models, program suites that analyse and evaluate the quality of other programs, but building good quality models is hard as there are many questions concerning quality modelling that have yet to be adequately addressed in the literature. We analysed quality modelling practices in a large organisation and identified three dimensions where research is needed: proper support of the subjective notion of quality, techniques to track the quality of evolving software, and the composition of quality judgments from different abstraction levels. To tackle subjectivity, we propose using Bayesian models as these can deal with uncertain data. We applied our models to the problem of anti-pattern detection. In a study of two open-source systems, we found that our approach was superior to state of the art rule-based techniques. To support software evolution, we consider scores produced by quality models as signals and the use of signal data-mining techniques to identify patterns in the evolution of quality. We studied how anti-patterns are introduced and removed from systems. Software is typically written using a hierarchy of components, yet quality models do not explicitly consider this hierarchy. As the last part of our dissertation, we present two level quality models. These are composed of three parts: a component-level model, a second model to evaluate the importance of each component, and a container-level model to combine the contribution of components with container attributes. This approach was tested on the prediction of class-level changes based on the quality and importance of its components: methods. It was shown to be more useful than single-level, traditional approaches. To finish, we reapplied this two-level methodology to the problem of assessing web site navigability. Our models could successfully distinguish award-winning sites from average sites picked at random. Throughout the dissertation, we present not only theoretical problems and solutions, but we performed experiments to illustrate the pros and cons of our solutions. Our results show that there are considerable improvements to be had in all three proposed dimensions. In particular, our work on quality composition and importance modelling is the first that focuses on this particular problem. We believe that our general two-level models are only a starting point for more in-depth research.
119

A unified framework for the comprehension of software's time dimension

Benomar, Omar 02 1900 (has links)
Les logiciels sont de plus en plus complexes et leur développement est souvent fait par des équipes dispersées et changeantes. Par ailleurs, de nos jours, la majorité des logiciels sont recyclés au lieu d’être développés à partir de zéro. La tâche de compréhension, inhérente aux tâches de maintenance, consiste à analyser plusieurs dimensions du logiciel en parallèle. La dimension temps intervient à deux niveaux dans le logiciel : il change durant son évolution et durant son exécution. Ces changements prennent un sens particulier quand ils sont analysés avec d’autres dimensions du logiciel. L’analyse de données multidimensionnelles est un problème difficile à résoudre. Cependant, certaines méthodes permettent de contourner cette difficulté. Ainsi, les approches semi-automatiques, comme la visualisation du logiciel, permettent à l’usager d’intervenir durant l’analyse pour explorer et guider la recherche d’informations. Dans une première étape de la thèse, nous appliquons des techniques de visualisation pour mieux comprendre la dynamique des logiciels pendant l’évolution et l’exécution. Les changements dans le temps sont représentés par des heat maps. Ainsi, nous utilisons la même représentation graphique pour visualiser les changements pendant l’évolution et ceux pendant l’exécution. Une autre catégorie d’approches, qui permettent de comprendre certains aspects dynamiques du logiciel, concerne l’utilisation d’heuristiques. Dans une seconde étape de la thèse, nous nous intéressons à l’identification des phases pendant l’évolution ou pendant l’exécution en utilisant la même approche. Dans ce contexte, la prémisse est qu’il existe une cohérence inhérente dans les évènements, qui permet d’isoler des sous-ensembles comme des phases. Cette hypothèse de cohérence est ensuite définie spécifiquement pour les évènements de changements de code (évolution) ou de changements d’état (exécution). L’objectif de la thèse est d’étudier l’unification de ces deux dimensions du temps que sont l’évolution et l’exécution. Ceci s’inscrit dans notre volonté de rapprocher les deux domaines de recherche qui s’intéressent à une même catégorie de problèmes, mais selon deux perspectives différentes. / Software systems are getting more and more complex and are developed by teams that are constantly changing and not necessarily working in the same location. Moreover, most software systems, nowadays, are recycled rather than being developed from scratch. A comprehension task is crucial when performing maintenance tasks; it consists of analyzing multiple software dimensions concurrently. Time is one of these dimensions, as software changes its state with time in two manners: during their execution and during their evolution. These changes make sense only when analyzed within the context of other software dimensions, such as structure or bug information. Multidimensional analysis is a difficult problem to solve. However, there are certain methods that bypass this difficulty, such as semi-automatic approaches. Software visualization is one of them, as it allows being part of the analysis by exploring and guiding information search. The first stage of the thesis consists of applying visualization techniques to better understand software dynamicity during execution and evolution. Changes over time are represented by heat maps. Hence, we utilize the same graphical representation to visualize both change types over time. Other approaches that permit the analysis of a program’s dynamic behavior over time involve the use of heuristics. In the thesis’ second stage, we are interested in the identification of the programs’ execution phases and evolution patterns using the same approach, i.e. search-based optimisation. In this context, the premise is the existence of internal cohesion between change events that allow the clustering in phases. This hypothesis of cohesion is defined specifically for change events in the code during software evolution and state changes during program execution. This thesis’ main objective is to study the unification of these two time dimensions, evolution and execution, in an attempt to bring together two research domains that work on the same set of problems, but from two different perspectives.
120

[en] SUPPORT FOR ARCHITECTURAL EVOLUTION IN COMPONENT-BASED DISTRIBUTED SYSTEMS / [pt] SUPORTE À EVOLUÇÃO ARQUITETURAL DE SISTEMAS DISTRIBUÍDOS BASEADOS EM COMPONENTES DE SOFTWARE

AIRTON JOSE ARAUJO LIBORIO 13 January 2015 (has links)
[pt] A natureza de certos sistemas de software determina que estes tenham de executar de maneira ininterrupta. Por outro lado, diversos sistemas de software são constantemente sujeitos a mudanças, por questões que incluem, mas não se limitam a, infraestrutura, correções de falhas, adição de funcionalidades e mudanças na lógica de domínio. Evolução dinâmica de software consiste em alterar aplicações durante a sua execução sem interrompê-las, mantendo-as disponíveis mesmo durante a aplicação destas modificações. Sistemas distribuídos baseados em componentes permitem decompor o software em entidades claramente separadas. Nesses casos, a evolução pode ser resumida a remoção, adição e modificação de tais entidades, e se tais atividades podem ser exercidas enquanto a aplicação está em execução, tem-se evolução dinâmica de software. Através disso, neste trabalho foi criada uma abordagem em que é possível se manipular arquiteturas distribuídas desenvolvidas sobre o middleware SCS de maneira a se minimizar a interrupção de partes do sistema enquanto certas adaptações são implantadas. Aplicamos o mecanismo em um sistema distribuído já consolidado, o CAS, que consiste em uma infraestrutura de gravação extensível com suporte a captura e acesso automáticos de mídias distribuídas. / [en] The nature of some software systems determine that they run without interruption. Furthermore, many software systems are constantly subject to change for reasons that include, but are not limited to, infrastructure changes, bug fixes, addition of functionalities, and changes in the domain logic. Dynamic software evolution consists into changing application during execution without stopping them, keeping them available even when applying these modifications. Component-based distributed systems allows decomposing software into clearly separated entities. In such cases, evolution can be summarized to removal, addition and modification of such entities, and if such activities can be performed while the application is executing, dynamic adaptation is achieved. In this work, we ve investigated an approach that aims to allow manipulation of distributed software architectures developed over the SCS middleware, in order to minimize system disruption while certain adaptations are deployed. The mechanism was tested in an already consolidated distributed system, the CAS, which consists of an extensible recording infrastructure that supports automatic capture and access of distributed medias.

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