Emilio Insfran

The OO-Method approach for information systems modeling: from object-oriented conceptual modeling to automated programming

Abstract Current and future (conventional) notations used in Conceptual Modeling Techniques should have a precise (formal) semantics to provide a well-defined software development process, in order to go from specification to implementation in an automated way. To achieve this objective, the OO-method approach to Information Systems Modeling presented in this paper attempts to overcome the conventional (informal)/formal dichotomy by selecting the best ideas from both approaches. The OO-method makes a clear distinction between the problem space (centered on what the system is) and the solution space (centered on how it is implemented as a software product). It provides a precise, conventional graphical notation to obtain a system description at the problem space level, however this notation is strictly based on a formal OO specification language that determines the conceptual modeling constructs needed to obtain the system specification. An abstract execution model determines how to obtain the software representations corresponding to these conceptual modeling constructs. In this way, the final software product can be obtained in an automated way.

Requirements Engineering-Based Conceptual Modelling

The software production process involves a set of phases where a clear relationship and smooth transitions between them should be introduced. In this paper, a requirements engineering-based conceptual modelling approach is introduced as a way to improve the quality of the software production process. The aim of this approach is to provide a set of techniques and methods to capture software requirements and to provide a way to move from requirements to a conceptual schema in a traceable way. The approach combines a framework for requirements engineering (TRADE) and a graphical object-oriented method for conceptual modelling and code generation (OO-Method). The intended improvement of the software production process is accomplished by providing a precise methodological guidance to go from the user requirements (represented through the use of the appropriate TRADE techniques) to the conceptual schema that properly represents them (according to the conceptual constructs provided by the OO-Method). Additionally, as the OO-Method provides full model-based code generation features, this combination minimises the time dedicated to obtaining the final software product.

A systematic review of the use of requirements engineering techniques in model-driven development

Model-Driven Development (MDD) emphasizes the use of models at a higher abstraction level in the software development process and argues in favor of automation via model execution, transformation, and code generation. However, one current challenge is how to manage requirements during this process whilst simultaneously stressing the benefits of automation. This paper presents a systematic review of the current use of requirements engineering techniques in MDD processes and their actual automation level. 72 papers from the last decade have been reviewed from an initial set of 884 papers. The results show that although MDD techniques are used to a great extent in platform-independent models, platform-specific models, and at code level, at the requirements level most MDD approaches use only partially defined requirements models or even natural language. We additionally identify several research gaps such as a need for more efforts to explicitly deal with requirements traceability and the provision of better tool support.

A Systematic Review of Usability Evaluation in Web Development

The challenge of developing more usable Web applications has motivated the appearance of a number of techniques, methods and tools to address Web usability issues. Although there are many proposals for supporting the development of usable Web applications, many developers are not aware of them and many organizations do not properly apply them. This paper reports on a systematic review of the use of usability evaluation methods in Web development. The objective of the review is to investigate what usability evaluation methods have been employed by researchers to evaluate Web artifacts and how they were employed. A total of 51 research papers have been reviewed from an initial set of 410 papers. The results show that 45% of the papers reviewed reported the use of evaluation methods specifically crafted for the Web and that the most employed method is user testing. In addition, the results of the review have identified several research gaps. Specifically, 80% of the evaluations are still performed at the implementation phase of Web applications development and 47% of the papers did not present any validation of the usability evaluation method(s) employed.

Assessing the Effectiveness of Sequence Diagrams in the Comprehension of Functional Requirements: Results from a Family of Five Experiments

Modeling is a fundamental activity within the requirements engineering process and concerns the construction of abstract descriptions of requirements that are amenable to interpretation and validation. The choice of a modeling technique is critical whenever it is necessary to discuss the interpretation and validation of requirements. This is particularly true in the case of functional requirements and stakeholders with divergent goals and different backgrounds and experience. This paper presents the results of a family of experiments conducted with students and professionals to investigate whether the comprehension of functional requirements is influenced by the use of dynamic models that are represented by means of the UML sequence diagrams. The family contains five experiments performed in different locations and with 112 participants of different abilities and levels of experience with UML. The results show that sequence diagrams improve the comprehension of the modeled functional requirements in the case of high ability and more experienced participants.

Early Usability Evaluation in Model Driven Architecture Environments

Due to the increasing interest in the model driven architecture (MDA) paradigm, the conceptual models have become the backbone of the software development process. So far some methods exist to develop a user interface according to a MDA-compliant method, none of them explicitly connects usability to their process activities. In this paper, we present a framework which incorporates usability as part of a MDA development process. In particular, a usability model for early evaluation is proposed. Using this model, the usability of a software system is evaluated and improved at the platform independent model (PIM) level. It focuses on the correspondences between the abstract user interface elements and the final user interface elements in a specific platform (CM). This framework has been successfully applied to an industrial MDA tool

A systematic review of quality attributes and measures for software product lines

It is widely accepted that software measures provide an appropriate mechanism for understanding, monitoring, controlling, and predicting the quality of software development projects. In software product lines (SPL), quality is even more important than in a single software product since, owing to systematic reuse, a fault or an inadequate design decision could be propagated to several products in the family. Over the last few years, a great number of quality attributes and measures for assessing the quality of SPL have been reported in literature. However, no studies summarizing the current knowledge about them exist. This paper presents a systematic literature review with the objective of identifying and interpreting all the available studies from 1996 to 2010 that present quality attributes and/or measures for SPL. These attributes and measures have been classified using a set of criteria that includes the life cycle phase in which the measures are applied; the corresponding quality characteristics; their support for specific SPL characteristics (e.g., variability, compositionality); the procedure used to validate the measures, etc. We found 165 measures related to 97 different quality attributes. The results of the review indicated that 92% of the measures evaluate attributes that are related to maintainability. In addition, 67% of the measures are used during the design phase of Domain Engineering, and 56% are applied to evaluate the product line architecture. However, only 25% of them have been empirically validated. In conclusion, the results provide a global vision of the state of the research within this area in order to help researchers in detecting weaknesses, directing research efforts, and identifying new research lines. In particular, there is a need for new measures with which to evaluate both the quality of the artifacts produced during the entire SPL life cycle and other quality characteristics. There is also a need for more validation (both theoretical and empirical) of existing measures. In addition, our results may be useful as a reference guide for practitioners to assist them in the selection or the adaptation of existing measures for evaluating their software product lines.

From Object Oriented Conceptual Modeling to Automated Programming in Java

The development of Internet commercial applications and corporate Intranets around the world, that often use Java as programming language, is a significant topic in modern Software Engineering. In this context, more than ever, well-defined methodologies and high-level tools are essential for developing quality software in a way that should be as independent as possible of the changes in technology. In this article, we present an OO method based on a formal object-oriented model. The main feature of this method is that developers’ efforts are focused on the conceptual modeling step, where analysts capture system requirements, and the full implementation can automatically be obtained following an execution model (including structure and behaviour). The final result is a web application with a three-tiered architecture, which is implemented in Java with a relational DBMS as object repository.

Evaluating requirements modeling methods based on user perceptions: A family of experiments

Numerous methods and techniques have been proposed for requirements modeling, although very few have had widespread use in practice. One drawback of requirements modeling methods is that they lack proper empirical evaluations. This means that there is a need for evaluation methods that consider both the theoretical and practical aspects of this type of methods and techniques. In this paper, we present a method for evaluating the quality of requirements modeling methods based on user perceptions. The evaluation method consists of a theoretical model that explains the relevant dimensions of quality for requirements modeling methods, along with a practical instrument with which to measure these quality dimensions. Basically, it allows us to predict the acceptance of a particular requirements modeling method in practice, based on the effort of applying the method, the quality of the requirements artifacts produced, and the user perceptions with regard to the quality of the method. The paper also presents an empirical test of the proposed method for evaluating a Rational Unified Process (RUP) extension for requirements modeling. That test was carried out through a family of experiments conducted with students and practitioners and provides evidence of the usefulness of the evaluation method proposed.

Integrating a Usability Model into Model-Driven Web Development Processes

Usability evaluations should start early in the Web development process and occur repeatedly throughout all stages to ensure the quality of the Web application, not just when the product is completed. This paper presents a Web Usability Model, which is aligned with the SQuaRE standard, to evaluate usability at several stages of a Web development process that follows a Model-Driven Development (MDD) approach. The Web Usability Model is generic and must be operationalized into a concrete MDD method by specifying the relationships between the usability attributes of the Usability Model and the modeling primitives of the specific Web development method. To illustrate the feasibility of the approach, we present a case study where the Usability Model has been applied in the evaluation of the models that are produced during the Web application development process.