Traduciendo OCL como lenguaje de consultas y restricciones

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Informática, Departamento de Sistemas Informáticos y Computación, leída el 30-06-2017Esta tesis doctoral debe gran parte de su motivación inicial y enfoque final a la discusión muy animada y perspicaz que tuvo lugar durante el seminario “Automated Reasoning on Conceptual Schemas” en Dagstuhl (19-24 Mayo, 2013) [18], en el cual tuvimos la fortuna de participar.Incluso antes de asistir al seminario, sobre la base de nuestra propia experiencia aplicando la metodología de desarrollo dirigida por modelos en el proyecto Action GUI [1],ya estábamos convencidos de la veracidad y la importancia de tres declaraciones claves contenidas en la presentación del mismo, que resumen muy bien las motivaciones finales de esta tesis:“La calidad de un sistema de información se determina en gran medida a principios del ciclo de desarrollo, es decir, durante la especificación de los requisitos y el modelado conceptual, ya que los errores introducidos en estas etapas suelen ser mucho más costosos de corregir que los errores cometidos durante el diseño o la implementación.”“Por lo tanto, es deseable prevenir, detectar y corregir errores tan pronto como sea posible en el proceso de desarrollo evaluando la corrección de los esquemas conceptuales construidos.”“La alta expresividad de los esquemas conceptuales requiere adoptar técnicas de razonamiento automatizadas para apoyar al diseñador en esta importante tarea.”...This doctoral dissertation owes a great deal of its initial motivation and final focusto the very lively and insightful discussion that took place during the Dagstuhl Seminar“Automated Reasoning on Conceptual Schemas” (19-24 May, 2013) [18], which we havethe fortune to participate in.Even before attending the seminar, based on our own experience applying the modeldrivendevelopment methodology within the ActionGUI project [1], we were already convincedof the truthfulness and importance of three key statements contained in the seminar’spresentation, which summarize very well this dissertation’s ultimate motivations:“The quality of an information system is largely determined early in the developmentcycle, i.e., during requirements specification and conceptual modeling, since errorsintroduced at these stages are usually much more expensive to correct than errorsmade during design or implementation.”“Thus, it is desirable to prevent, detect, and correct errors as early as possible in thedevelopment process by assessing the correctness of the conceptual schemas built.”“The high expressivity of conceptual schemas requires to adopt automated reasoningtechniques to support the designer in this important task.”..Depto. de Sistemas Informáticos y ComputaciónFac. de InformáticaTRUEunpu

Metamodel Instance Generation: A systematic literature review

Modelling and thus metamodelling have become increasingly important in Software Engineering through the use of Model Driven Engineering. In this paper we present a systematic literature review of instance generation techniques for metamodels, i.e. the process of automatically generating models from a given metamodel. We start by presenting a set of research questions that our review is intended to answer. We then identify the main topics that are related to metamodel instance generation techniques, and use these to initiate our literature search. This search resulted in the identification of 34 key papers in the area, and each of these is reviewed here and discussed in detail. The outcome is that we are able to identify a knowledge gap in this field, and we offer suggestions as to some potential directions for future research.Comment: 25 page

Checking Unsatisfiability for OCL Constraints

In this paper we propose a mapping from a subset of OCL into first-order logic (FOL) and use this mapping for checking the unsatisfiability of sets of OCL constraints. Although still preliminary work, we argue in this paper that our mapping is both simple, since the resulting FOL sentences closely mirror the original OCL constraints, and practical, since we can use automated reasoning tools, such as automated theorem provers and SMT solvers to automatically check the unsatisfiability of non-trivial sets of OCL constraints

Testing and test-driven development of conceptual schemas

The traditional focus for Information Systems (IS) quality assurance relies on the evaluation of its implementation. However, the quality of an IS can be largely determined in the first stages of its development. Several studies reveal that more than half the errors that occur during systems development are requirements errors. A requirements error is defined as a mismatch between requirements specification and stakeholders¿ needs and expectations. Conceptual modeling is an essential activity in requirements engineering aimed at developing the conceptual schema of an IS. The conceptual schema is the general knowledge that an IS needs to know in order to perform its functions. A conceptual schema specification has semantic quality when it is valid and complete. Validity means that the schema is correct (the knowledge it defines is true for the domain) and relevant (the knowledge it defines is necessary for the system). Completeness means that the conceptual schema includes all relevant knowledge. The validation of a conceptual schema pursues the detection of requirements errors in order to improve its semantic quality. Conceptual schema validation is still a critical challenge in requirements engineering. In this work we contribute to this challenge, taking into account that, since conceptual schemas of IS can be specified in executable artifacts, they can be tested. In this context, the main contributions of this Thesis are (1) an approach to test conceptual schemas of information systems, and (2) a novel method for the incremental development of conceptual schemas supported by continuous test-driven validation. As far as we know, this is the first work that proposes and implements an environment for automated testing of UML/OCL conceptual schemas, and the first work that explores the use of test-driven approaches in conceptual modeling. The testing of conceptual schemas may be an important and practical means for their validation. It allows checking correctness and completeness according to stakeholders¿ needs and expectations. Moreover, in conjunction with the automatic check of basic test adequacy criteria, we can also analyze the relevance of the elements defined in the schema. The testing environment we propose requires a specialized language for writing tests of conceptual schemas. We defined the Conceptual Schema Testing Language (CSTL), which may be used to specify automated tests of executable schemas specified in UML/OCL. We also describe a prototype implementation of a test processor that makes feasible the approach in practice. The conceptual schema testing approach supports test-last validation of conceptual schemas, but it also makes sense to test incomplete conceptual schemas while they are developed. This fact lays the groundwork of Test-Driven Conceptual Modeling (TDCM), which is our second main contribution. TDCM is a novel conceptual modeling method based on the main principles of Test-Driven Development (TDD), an extreme programming method in which a software system is developed in short iterations driven by tests. We have applied the method in several case studies, in the context of Design Research, which is the general research framework we adopted. Finally, we also describe an integration approach of TDCM into a broad set of software development methodologies, including the Unified Process development methodology, MDD-based approaches, storytest-driven agile methods and goal and scenario-oriented requirements engineering methods.Els enfocaments per assegurar la qualitat deis sistemes d'informació s'han basal tradicional m en! en l'avaluació de la seva implementació. No obstan! aix6, la qualitat d'un sis tema d'informació pot ser ampliament determinada en les primeres fases del seu desenvolupament. Diversos estudis indiquen que més de la meitat deis errors de software són errors de requisits . Un error de requisit es defineix com una desalineació entre l'especificació deis requisits i les necessitats i expectatives de les parts im plicades (stakeholders ). La modelització conceptual és una activitat essencial en l'enginyeria de requisits , l'objectiu de la qual és desenvolupar !'esquema conceptual d'un sistema d'informació. L'esquema conceptual és el coneixement general que un sistema d'informació requereix per tal de desenvolupar les seves funcions . Un esquema conceptual té qualitat semantica quan és va lid i complet. La valides a implica que !'esquema sigui correcte (el coneixement definit és cert peral domini) i rellevant (el coneixement definit és necessari peral sistema). La completes a significa que !'esquema conceptual inclou tot el coneixement rellevant. La validació de !'esquema conceptual té coma objectiu la detecció d'errors de requisits per tal de millorar la qualitat semantica. La validació d'esquemes conceptuals és un repte crític en l'enginyeria de requisits . Aquesta te si contribueix a aquest repte i es basa en el fet que els es quemes conceptuals de sistemes d'informació poden ser especificats en artefactes executables i, per tant, poden ser provats. Les principals contribucions de la te si són (1) un enfocament pera les pro ves d'esquemes conceptuals de sistemes d'informació, i (2) una metodología innovadora pel desenvolupament incremental d'esquemes conceptuals assistit per una validació continuada basada en proves . Les pro ves d'esquemes conceptuals poden ser una im portant i practica técnica pera la se va validació, jaque permeten provar la correctesa i la completesa d'acord ambles necessitats i expectatives de les parts interessades. En conjunció amb la comprovació d'un conjunt basic de criteris d'adequació de les proves, també podem analitzar la rellevancia deis elements definits a !'esquema. L'entorn de test proposat inclou un llenguatge especialitzat per escriure proves automatitzades d'esquemes conceptuals, anomenat Conceptual Schema Testing Language (CSTL). També hem descrit i implementa! a un prototip de processador de tes tos que fa possible l'aplicació de l'enfocament proposat a la practica. D'acord amb l'estat de l'art en validació d'esquemes conceptuals , aquest és el primer treball que proposa i implementa un entorn pel testing automatitzat d'esquemes conceptuals definits en UML!OCL. L'enfocament de proves d'esquemes conceptuals permet dura terme la validació d'esquemes existents , pero també té sentit provar es quemes conceptuals incomplets m entre estant sent desenvolupats. Aquest fet és la base de la metodología Test-Driven Conceptual Modeling (TDCM), que és la segona contribució principal. El TDCM és una metodología de modelització conceptual basada en principis basics del Test-Driven Development (TDD), un métode de programació en el qual un sistema software és desenvolupat en petites iteracions guiades per proves. També hem aplicat el métode en diversos casos d'estudi en el context de la metodología de recerca Design Science Research. Finalment, hem proposat enfocaments d'integració del TDCM en diverses metodologies de desenvolupament de software

Ensuring the semantic correctness of a BAUML artifact-centric BPM

Context: Using models to represent business processes provides several advantages, such as facilitating the communication between the stakeholders or being able to check the correctness of the processes before their implementation. In contrast to traditional process modeling approaches, the artifact-centric approach treats data as a key element of the process, also considering the tasks or activities that are performed in it. Objective: This paper presents a way to verify and validate the semantic correctness of an artifact-centric business process model defined using a combination of UML and OCL models - a BAUML model. Method: We achieve our goal by presenting several algorithms that encode the initial models into first-order logic, which then allows to use an existing satisfiability checking tool to determine their correctness. Results: An approach to verify and validate an artifact-centric BPM specified in BAUML, which uses a combination of UML and OCL models. To do this, we provide a method to translate all BAUML components into a set of logic formulas. The result of this translation ensures that the only changes allowed are those specified in the model, and that those changes are taking place according the order established by the model. Having obtained this logic representation, these models can be validated by any existing reasoning method able to deal with negation of derived predicates. Moreover, we show how to automatically generate the relevant tests to validate the models. We also show the feasibility of our approach by implementing a prototype tool and applying it to a running example. Conclusion: It is feasible to ensure the semantic correctness of an artifact-centric business process model in practice.Peer ReviewedPostprint (author's final draft

Reasoning & Querying – State of the Art

Various query languages for Web and Semantic Web data, both for practical use and as an area of research in the scientific community, have emerged in recent years. At the same time, the broad adoption of the internet where keyword search is used in many applications, e.g. search engines, has familiarized casual users with using keyword queries to retrieve information on the internet. Unlike this easy-to-use querying, traditional query languages require knowledge of the language itself as well as of the data to be queried. Keyword-based query languages for XML and RDF bridge the gap between the two, aiming at enabling simple querying of semi-structured data, which is relevant e.g. in the context of the emerging Semantic Web. This article presents an overview of the field of keyword querying for XML and RDF

Tool Paper: A Lightweight Formal Encoding of a Constraint Language for DSMLs

International audienceDomain Specific Modeling Languages (dsmls) plays a key role in the development of Safety Critical Systems to model system requirements and implementation. They often need to integrate property and query sub-languages. As a standardized modeling language, ocl can play a key role in their definition as they can rely both on its concepts and textual syntax which are well known in the Model Driven Engineering community. For example, most dsmls are defined using mof for their abstract syntax and ocl for their static semantics as a metamodeling dsml. OCLinEcore in the Eclipse platform is an example of such a metamodeling dsml integrating ocl as a language component in order to benefit from its property and query facilities. dsmls for Safety Critical Systems usually provide formal model verification activities for checking models completeness or consistency, and implementation correctness with respect to requirements. This contribution describes a framework to ease the definition of such formal verification tools by relying on a common translation from a subset of ocl to the Why3 verification toolset. This subset was selected to ease efficient automated verification. This framework is illustrated using a block specification language for data flow languages where a subset of ocl is used as a component language