Omar Alam

Concern-Oriented Software Design

There exist many solutions to solve a given design problem, and it is difficult to capture the essence of a solution and make it reusable for future designs. Furthermore, many variations of a given solution may exist, and choosing the best alternative depends on application-specific high-level goals and non-functional requirements. This paper proposes Concern-Oriented Software Design, a modelling technique that focuses on concerns as units of reuse. A concern groups related models serving the same purpose, and provides three interfaces to facilitate reuse. The variation interface presents the design alternatives and their impact on non-functional requirements. The customization interface of the selected alternative details how to adapt the generic solution to a specific context. Finally, the usage interface specifies the provided behaviour. We illustrate our approach by presenting the concern models of variations of the Observer design pattern, which internally depends on the Association concern to link observers and subjects.

TouchRAM: A Multitouch-Enabled Tool for Aspect-Oriented Software Design

This paper presents TouchRAM, a multitouch-enabled tool for agile software design modeling aimed at developing scalable and reusable software design models. The tool gives the designer access to a vast library of reusable design models encoding essential recurring design concerns. It exploits model interfaces and aspect-oriented model weaving techniques as defined by the Reusable Aspect Models (RAM) approach to enable the designer to rapidly apply reusable design concerns within the design model of the software under development. The paper highlights the user interface features of the tool specifically designed for ease of use, reuse and agility (multiple ways of input, tool-assisted reuse, multitouch), gives an overview of the library of reusable design models available to the user, and points out how the current state-of-the-art in model weaving had to be extended to support seamless model reuse.

Feature modelling and traceability for concern-driven software development with TouchCORE

This demonstration paper presents TouchCORE, a multi-touch enabled software design modelling tool aimed at developing scalable and reusable software design models following the concerndriven software development paradigm. After a quick review of concern-orientation, this paper primarily focusses on the new features that were added to TouchCORE since the last demonstration at Modularity 2014 (were the tool was still called TouchRAM). TouchCORE now provides full support for concern-orientation. This includes support for feature model editing and different modes for feature model and impact model visualization and assessment to best assist the concern designers as well as the concern users. To help the modeller understand the interactions between concerns, TouchCORE now also collects tracing information when concerns are reused and stores that information with the woven models. This makes it possible to visualize from which concern(s) a model element in the woven model has originated.

Using CVL to operationalize product line development with reusable aspect models

This paper proposes a software design modelling approach that uses the Common Variability Language (CVL) to specify and resolve the variability of a software design, and the aspect-oriented modelling technique Reusable Aspect Models (RAM) to specify and then compose the detailed structural and behavioural design models corresponding to the chosen variants. This makes it possible to 1) exploit the advanced modularization capabilities of RAM to specify a complex, detailed design concern and its variants by means of a set of interdependent aspect models; 2) use CVL to provide an easy-to-use product-line interface for the design concern; 3) automatically generate a detailed design model for a chosen variant using a custom generic CVL derivation operator and the RAM weaver.

VCU: The Three Dimensions of Reuse

Reuse, enabled by modularity and interfaces, is one of the most important concepts in software engineering. This is evidenced by an increasingly large number of reusable artifacts, ranging from small units such as classes to larger, more sophisticated units such as components, services, frameworks, software product lines, and concerns. This paper presents evidence that a canonical set of reuse interfaces has emerged over time: the variation, customization, and usage interfaces VCU. A reusable artifact that provides all three interfaces reaches the highest potential of reuse, as it explicitly exposes how the artifact can be manipulated during the reuse process along these three dimensions. We demonstrate the wide applicability of the VCU interfaces along two axes: across abstraction layers of a system specification and across existing reuse techniques. The former is shown with the help of a comprehensive case study including reusable requirements, software, and hardware models for the authorization domain. The latter is shown with a discussion on how the VCU interfaces relate to existing reuse techniques.

On the modularization provided by concern-oriented reuse

Reuse is essential in modern software engineering, and hence also in the context of model-driven engineering (MDE). Concern-Oriented Reuse (CORE) proposes a new way of structuring model-driven software development where models of the system are modularized by domains of abstraction within units of reuse called concerns. Within a concern, models are further decomposed and modularized by views and features. High-level concerns can reuse lower-level concerns, and models within a concern can extend other models belonging to the same concern, resulting in complex inter- and intra-concern dependencies. To clearly specify what dependencies are allowed between models belonging to the same or to different concerns, CORE advocates a three-part interface to describe each concern (variation, customization, and usage interfaces). This paper presents the CORE metamodel that formalizes the CORE concepts and enables the integration of different mod- elling languages within the CORE framework.

TouchRAM: a multitouch-enabled software design tool supporting concern-oriented reuse

TouchRAM is a multitouch-enabled tool for agile software design modelling aimed at developing scalable and reusable software design models. This paper primarily focusses on the new features that were added to TouchRAM to provide initial support for concern-orientation, and then summarizes the new extensions to behavioural modelling and improved integration with Java. A video that demonstrates the use of TouchRAM can be found here: http://www.youtube.com/watch?v=l8LMqwwRPg4

Delaying decisions in variable concern hierarchies

Concern-Oriented Reuse (CORE) proposes a new way of structuring model-driven software development, where models of the system are modularized by domains of abstraction within units of reuse called concerns. Within a CORE concern, models are further decomposed and modularized by features. This paper extends CORE with a technique that enables developers of high-level concerns to reuse lower-level concerns without unnecessarily committing to a specific feature selection. The developer can select the functionality that is minimally needed to continue development, and reexpose relevant alternative lower-level features of the reused concern in the reusing concerns interface. This effectively delays decision making about alternative functionality until the higher-level reuse context, where more detailed requirements are known and further decisions can be made. The paper describes the algorithms for composing the variation (i.e., feature and impact models), customization, and usage interfaces of a concern, as well as the concerns realization models and finally an entire concern hierarchy, as is necessary to support delayed decision making in CORE.

Assessing composition in modeling approaches

Modeling approaches are based on various paradigms, e.g., aspect-oriented, feature-oriented, object-oriented, and logic-based. Modeling approaches may cover requirements models to low-level design models, are developed for various purposes, use various means of composition, and thus are difficult to compare. However, such comparisons are critical to help practitioners know under which conditions approaches are most applicable, and how they might be successfully generalized and combined to achieve end-to-end methods. This paper reports on work done at the 2nd International Comparing Modeling Approaches (CMA) workshop towards the goal of identifying potential comprehensive modeling methodologies with a particular emphasis on composition: (i) an improved set of comparison criteria; (ii) 19 assessments of modeling approaches based on the comparison criteria and a common, focused case study.

Comparing six modeling approaches

While there are many aspect-oriented modeling (AOM) approaches, from requirements to low-level design, it is still difficult to compare them and know under which conditions different approaches are most applicable. This comparison, however, is crucially important to unify existing AOM and more traditional object-oriented modeling (OOM) approaches and to generalize individual approaches into a comprehensive end-to-end method. Such a method does not yet exist. This paper reports on work done at the inaugural Comparing Modeling Approaches (CMA) workshop towards the goal of identifying potential comprehensive methodologies: (i) a common, focused case study for six modeling approaches, (ii) a set of criteria applied to each of the six approaches, and (iii) the assessment results.