Pattern Reification as the Basis for Description-Driven Systems

One of the main factors driving object-oriented software development for information systems is the requirement for systems to be tolerant to change. To address this issue in designing systems, this paper proposes a pattern-based, object-oriented, description-driven system (DDS) architecture as an extension to the standard UML four-layer meta-model. A DDS architecture is proposed in which aspects of both static and dynamic systems behavior can be captured via descriptive models and meta-models. The proposed architecture embodies four main elements - firstly, the adoption of a multi-layered meta-modeling architecture and reflective meta-level architecture, secondly the identification of four data modeling relationships that can be made explicit such that they can be modified dynamically, thirdly the identification of five design patterns which have emerged from practice and have proved essential in providing reusable building blocks for data management, and fourthly the encoding of the structural properties of the five design patterns by means of one fundamental pattern, the Graph pattern. A practical example of this philosophy, the CRISTAL project, is used to demonstrate the use of description-driven data objects to handle system evolution.Comment: 20 pages, 10 figure

Towards UML Modelling Extra-Functional Properties in Web Services and their Clients

Web Services provide our systems with a platform independent and loosely coupled implementation environment, being time to face how the named systems can be modelled. Service Component Architecture (SCA) allows us to define services independently of the final implementation technology; however, it does not integrate the remaining development stages. Model Driven Architecture provides a method to face all stages in development from the platform independent model to final code, although it is not specific to service technologies. Regarding web service extra-functional properties, WS-Policy establishes how to describe them in a loosely coupled manner; however the loosely coupled environment is not always maintained when modelling or implementing these properties, which can be solved by using aspect-oriented techniques. In this paper, we propose to use a model driven approach for extra-functional properties in SCA service based models, where generated code will consist of the policy description and an aspect-oriented implementation

Modelling electronic service systems using UML

This paper presents a profile for modelling systems of electronic services using UML. Electronic services encapsulate business services, an organisational unit focused on delivering benefit to a consumer, to enhance communication, coordination and information management. Our profile is based on a formal, workflow-oriented description of electronic services that is abstracted from particular implementation technologies. Resulting models provide the basis for a formal analysis to verify behavioural properties of services. The models can also relate services to management components, including workflow managers and Electronic Service Management Systems (ESMSs), a novel concept drawn from experience of HP Service Composer and DySCo (Dynamic Service Composer), providing the starting point for integration and implementation tasks. Their UML basis and platform-independent nature is consistent with a Model-Driven Architecture (MDA) development strategy, appropriate to the challenge of developing electronic service systems using heterogeneous technology, and incorporating legacy systems

Reliability prediction in model driven development

Evaluating the implications of an architecture design early in the software development lifecycle is important in order to reduce costs of development. Reliability is an important concern with regard to the correct delivery of software system service. Recently, the UML Profile for Modeling Quality of Service has defined a set of UML extensions to represent dependability concerns (including reliability) and other non-functional requirements in early stages of the software development lifecycle. Our research has shown that these extensions are not comprehensive enough to support reliability analysis for model-driven software engineering, because the description of reliability characteristics in this profile lacks support for certain dynamic aspects that are essential in modeling reliability. In this work, we define a profile for reliability analysis by extending the UML 2.0 specification to support reliability prediction based on scenario specifications. A UML model specified using the profile is translated to a labelled transition system (LTS), which is used for automated reliability prediction and identification of implied scenarios; the results of this analysis are then fed back to the UML model. The result is a comprehensive framework for addressing software reliability modeling, including analysis and evolution of reliability predictions. We exemplify our approach using the Boiler System used in previous work and demonstrate how reliability analysis results can be integrated into UML models

Detecting the Onset of Dementia using Context-Oriented Architecture

In the last few years, Aspect Oriented Software De- velopment (AOSD) and Context Oriented Software Development (COSD) have become interesting alternatives for the design and construction of self-adaptive software systems. An analysis of these technologies shows them all to employ the principle of the separation of concerns, Model Driven Architecture (MDA) and Component-based Software Development (CBSD) for building high quality of software systems. In general, the ultimate goal of these technologies is to be able to reduce development costs and effort, while improving the adaptability, and dependability of software systems. COSD, has emerged as a generic devel- opment paradigm towards constructing self-adaptive software by integrating MDA with context-oriented component model. The self-adaptive applications are developed using a Context- Oriented Component-based Applications Model-Driven Architec- ture (COCA-MDA), which generates an Architecture Description language (ADL) presenting the architecture as a components- based software system. COCA-MDA enables the developers to modularise the application based on their context-dependent behaviours, and separate the context-dependent functionality from the context-free functionality of the application. In this article, we wish to study the impact of the decomposition mechanism performed in MDA approaches over the software self-adaptability. We argue that a better and significant advance in software modularity based on context information can increase software adaptability and increase their performance and modi- fiability

An Architecture Description Language for Embedded Hardware Platforms

Embedded software development relies on various tools - compilers, simulators, execution time estimators - that encapsulate a more-or-less detailed knowledge of the target hardware platform. These tools can be costly to develop and maintain:significant benefits could be expected if they were automatically generated from models expressed in a dedicated modeling language.In contrast with Hardware Description Languages (HDLs), that focus on the internal structure and behavior of an electronic board of chip, Hardware Architecture Description Languages consider hardware as a platform for software execution. Such a platform will be described in terms of low-level programming interface (processor instruction set),resources (processing elements, memory and peripheral devices) and elementary services (arithmetic and logic operations, bus transactions).This paper gives an overview of HARMLESS (Hardware ARchitecture Modeling Language for Embedded Software Simulation), a new domain-specific language for modeling embedded hardware platforms. HARMLESS and its associated tools follow the Model-Driven Engineering philosophy: metamodeling and model transformations have been successfully applied to the automatic generation of processor simulators

An Architecture Description Language for Embedded Hardware Platforms

Embedded software development relies on various tools - compilers, simulators, execution time estimators - that encapsulate a more-or-less detailed knowledge of the target hardware platform. These tools can be costly to develop and maintain:significant benefits could be expected if they were automatically generated from models expressed in a dedicated modeling language.In contrast with Hardware Description Languages (HDLs), that focus on the internal structure and behavior of an electronic board of chip, Hardware Architecture Description Languages consider hardware as a platform for software execution. Such a platform will be described in terms of low-level programming interface (processor instruction set),resources (processing elements, memory and peripheral devices) and elementary services (arithmetic and logic operations, bus transactions).This paper gives an overview of HARMLESS (Hardware ARchitecture Modeling Language for Embedded Software Simulation), a new domain-specific language for modeling embedded hardware platforms. HARMLESS and its associated tools follow the Model-Driven Engineering philosophy: metamodeling and model transformations have been successfully applied to the automatic generation of processor simulators

Mobile Museum Guides Applications based on Knowledge Graphs

In the paper, we discuss our experience in design and development of a content consumption focused mobile applications with data sources in the form of Linked Data by the example of developing museum guide application for The State Russian Museum. We describe our approach to formalizing a model in a dynamictyped programming language (JavaScript) and the way to keep it consistent. The paper contains the description of the system’s main component: a framework for generating a model from an ontology. Ontology-based application architecture can facilitate Domain Driven Design approach, and we demonstrate the ways how to combine these techniques in practice. Lastly, we discuss challenges and problems we faced during the development, then present our conclusions and future direction for exploration

Productivity Evaluation of Self-Adaptive Software Model Driven Architecture

Anticipating context changes using a model-based approach requires a formal procedure for analysing and modelling context-dependent functionality and stable description of the architecture which supports dynamic decision-making and architecture evolution. This article demonstrates the capabilities of the context-oriented component-based application-model-driven architecture (COCA-MDA) to support the development of self- adaptive applications; the authors describe a state-of-the-art case study and evaluate the development effort involved in adopting the COCA-MDA in constructing the application. An intensive analysis of the applica- tion requirements simplified the process of modelling the application’s behavioural model; therefore, instead of modelling several variation models, the developers modelled an extra-functionality model. COCA-MDA reduces the development effort because it maintains a clear separation of concerns and employs a decom- position mechanism to produce a context-oriented component model which decouples the applications’ core functionality from the context-dependent functionality. Estimating the MDA approach’s productivity can help the software developers select the best MDA-based methodology from the available solutions. Thus, counting the source line of code is not adequate for evaluating the development effort of the MDA-based methodology. Quantifying the maintenance adjustment factor of the new, adapted, and reused code is a better estimate of the development effort of the MDA approaches