Sergio España

Communication Analysis: A Requirements Engineering Method for Information Systems

Developing Information Systems (ISs) is a hard task for which Requirements Engineering (RE) offers a good starting point. ISs can be viewed as a support for organisational communication. Therefore, we argue in favour of communication-oriented RE methods. This paper presents Communication Analysis, a method for IS development and computerisation. The focus is put on requirements modelling techniques. Two novel techniques are described; namely, Communicative Event Diagram and Communication Structures. These are based on sound theory, they are accompanied by prescriptive guidelines (such as unity criteria) and they are illustrated by means of a practical example.

Model-Driven Development

The model-driven architecture (MDA) paradigm is well-known and widely used in the field of model-based software development. However, there are still some issues that are problematic and that need to be dealt with carefully. In this paper we present a metaphor that explains how MDA grows in complexity as problems faced become more difficult or “wicked”, and how a method designed to be powerful, flexible and MDA-compliant can eventually become, in effect, a “jigsaw puzzle”. This jigsaw puzzle is not merely the result of having a collection of methodological “pieces” with routes across them, but also arises as a result of the criteria underlying the MDA abstraction layers. We compare MDA to other research fields such as human-computer interaction, model management and method engineering, and we use as an example the OO-Method, a software development method based on MDA-compliant model transformations. We focus on a methodological piece that is conceived to allow the specification of interaction requirements by means of interface sketches. These sketches are supported by a task model that serves as a sound basis for formalisation and allows the application of model transformation in order to obtain subsequent models. A case study illustrates the requirements capture method together with the software development process defined by the OO-Method. The whole process presented in the case study represents one of the possible routes that can be followed when developing a software system with the OO-Method.

Evaluating the Completeness and Granularity of Functional Requirements Specifications: A Controlled Experiment

Requirements Engineering (RE) is a relatively young discipline, and still many advances have been achieved during the last decades. In particular, numerous RE methods have been proposed. However, there is a growing concern for empirical validations that assess RE proposals and statements. This paper is related to the evaluation of the quality of functional requirements specifications, focusing on completeness and granularity. To do this, several concepts related to conceptual model quality are presented; these concepts lead to the definition of metrics that allow measuring certain aspects of a requirements model quality (e.g. degree of functional encapsulations completeness with respect to a reference model, number of functional fragmentation errors). A laboratory experiment with master students has been carried out, in order to compare (using the proposed metrics) two RE approaches; namely, Use Cases and Communication Analysis. Results indicate greater quality (in terms of completeness and granularity) when Communication Analysis guidelines are followed. Moreover, interesting issues arise from experimental results, which invite further research.

An empirical comparative evaluation of requirements engineering methods

Requirements Engineering (RE) is a relatively young discipline, and still many advances have been achieved during the last decades. In particular, numerous RE approaches are proposed in the literature with the aim of understanding a certain problem (e.g. information systems development) and establishing a knowledge base that is shared between domain experts and developers (i.e. a requirements specification). However, there is a growing concern for empirical validations that assess RE proposals and statements. This paper is related to the assessment of the quality of functional requirements specifications, using the Method Evaluation Model (MEM) as a theoretical framework. The MEM distinguishes the actual efficacy and the perceived efficacy of a method. In order to assess the actual efficacy or RE methods, the conceptual model quality framework by Lindland et al. can be applied; in this paper, we focus on the completeness and granularity of requirements models and extend this framework by defining four new metrics (e.g. degree of functional encapsulations completeness with respect to a reference model, number of functional fragmentation errors). In order to assess the perceived efficacy, conventional questionnaires can be used. A laboratory experiment with master students has been carried out, in order to compare (using the proposed metrics) two RE methods; namely, Use Cases and Communication Analysis. With respect to actual efficacy, results indicate greater model quality (in terms of completeness and granularity) when Communication Analysis guidelines are followed. With respect to perceived efficacy, we found that Use Cases was perceived to be slightly easier to use than Communication Analysis. However, Communication Analysis was perceived to be more useful in terms of determining the proper business processes granularity. The paper discusses these results and highlights some key issues for future research in this area.

Systematic Derivation of Class Diagrams from Communication-Oriented Business Process Models

Enterprise information systems can be developed following a model-driven paradigm. This way, models that represent the organisational work practice are used to produce models that represent the information system. Current software development methods are starting to provide guidelines for the construction of conceptual models, taking as input requirements models. This paper proposes the integration of two methods: Communication Analysis (a communication-oriented requirements engineering method [1]) and the OO Method (a model-driven object-oriented software development method [2]). For this purpose, a systematic technique for deriving class diagrams from business process models is proposed. The business process specifications (which include message structures) are processed in order to obtain class diagram views, which are integrated to create the class diagram incrementally. Then, using the olivanova framework, software source code can be generated automatically. The paper also discusses the advantages and current limitations of the technique. Results show that, although there is room for improvement, the technique is feasible and it does facilitate the creation of the class diagram.

Dealing with Usability in Model Transformation Technologies

Nowadays, the concept of Model Transformation Technology (MTT) is widely accepted in the Software Engineering community. These technologies have the capability of generating software code (solution space) from a conceptual model that specifies the system abstractly (problem space). Most MTTs disregard interaction modelling (and specifically usability modelling), even though usability is as important as functionality to produce high-quality software. The issue of ensuring usability has been researched from several perspectives. One of these perspectives is based on elaborating the information to be discussed with the user to gather usability needs and the modifications to be done in software design to support those needs. We adopt this perspective by using guidelines to capture usability requirements and architectural usability patterns. The main contribution of this paper is to propose a strategy to include existing usability features inside a complete Model Transformation Technology, from abstract modelling to code generation. In order to reach this goal, new conceptual primitives have to be defined using as a source the description of the usability features. The analyst uses these primitives to model the functionality of the usability features. Once the strategy is defined in general terms, it is applied to a specific Model Transformation Technology: the OO-Method.

Integrating Business Domain Ontologies with Early Requirements Modelling

Requirements engineering is an important and complex phase during systems development because it combines the description of the systems domain with the elicitation, specification and validation of application-specific requirements. In this paper we propose an ontology-based requirements engineering approach that integrates the use of domain ontologies to capture domain knowledge into early requirements modelling techniques, which primarily aim at eliciting and representing the organisational and intentional context of the system. The proposed approach can be used with different types of domain ontologies and different requirements engineering techniques. The approach is illustrated using the REA enterprise ontology, the E3-value ontology and the i* requirements modelling framework.

Conceptual Alignment of Software Production Methods

From an Information Systems (IS) perspective, a myriad of specific approaches exist to deal with the different parts of a software production process. How to align them correctly taking a conceptual approach is still a very open problem. Instead of facing how to incrementally improve pre-existing methods, more and more proposals that are based on different paradigms or combine current IS concepts in some apparently innovative way are introduced. The conclusion of all of this is that, more than ever, we should concentrate on the essentials of IS modelling. A set of precise concepts is essential to be able to understand what each technique offers. A conceptual reference framework is needed to appropriately align the different proposals. This work presents a conceptual framework to be used for the conceptual alignment of software production methods. As a practical application, it is applied to the OO-Method, which is a conceptual model-based software production method, in order to show how the different pieces of the method fit the proposed framework conceptually.

Integrating the goal and business process perspectives in information system analysis

There are several motivations to promote investment and scientific effort in the integration of intentional and operational perspectives: organisational reengineering, continuous improvement of business processes, alignment among complementary analysis perspectives, information traceability, etc. In this paper we propose the integration of two modelling languages that support the creation of goal and business process models: the i* goal-oriented modelling method and Communication Analysis, a communication-oriented business process modelling method. We describe the methodological integration of the two modelling methods with the aim of fulfilling several criteria: i) to rely on appropriate theories; ii) to provide abstract and concrete syntaxes; iii) to provide scenarios of application; and iv) to develop tool support. We provide guidelines for using the two modelling methods in a top-down analysis scenario. We also present an illustrative case that demonstrates the feasibility of the approach.

EERMM: a metamodel for the enhanced entity-relationship model

A metamodel describes the elements of a model, the relationships between them, and the structuring rules that constraint the model elements and the way they are arranged/related in order to respect the domain rules. That is, a metamodel provides an abstract syntax to distinguish between valid and invalid models. Although the Enhanced Entity-Relationship (EER) model has been extensively researched, and various extensions and enhancements have been proposed, to the best of our knowledge, a metamodel for the EER model, based on the classical notation of Chen, has not been proposed yet. That is, we have found no evidence of a metamodel that gives a precise and expressive definition of constructors and constructions needed to create, interchange or transform valid EER models. With aim of overcoming these shortcoming, in this paper we propose an expressive metamodel for EER modeling, named EER MetaModel (EERMM), which provides a novel perspective for scientific researches and industrial applications that need an EER metamodel as a starting point. As a proof of concept, we have implemented a CASE tool (EERCASE) according to our metamodel and, by exploiting this tool, we have designed an EER schema that makes use of all constructors of the EER model.