Managing conflicts in aspect-oriented software

Aspect-Oriented Software Development is an approach which supports the modularisation of crosscutting concerns through the development phases of an application. One of the limitations in the main approaches to AOSD is that they do not provide support for the definition and handling of conflicts that may arise between multiple competing aspects. This paper describes how conflicts are managed by a framework that we have developed for the construction of aspect-oriented applications. In the first place, we describe the main characteristics of this reflective multi-level framework and the tool that instantiates it. We then present our categorisation of different conflicts and how they are defined and handled by our environment for the development of aspect-oriented software.Eje: Ingeniería de SoftwareRed de Universidades con Carreras en Informática (RedUNCI

Managing conflicts in aspect-oriented software

Aspect-Oriented Software Development is an approach which supports the modularisation of crosscutting concerns through the development phases of an application. One of the limitations in the main approaches to AOSD is that they do not provide support for the definition and handling of conflicts that may arise between multiple competing aspects. This paper describes how conflicts are managed by a framework that we have developed for the construction of aspect-oriented applications. In the first place, we describe the main characteristics of this reflective multi-level framework and the tool that instantiates it. We then present our categorisation of different conflicts and how they are defined and handled by our environment for the development of aspect-oriented software.Eje: Ingeniería de SoftwareRed de Universidades con Carreras en Informática (RedUNCI

ABC/ADL: An ADL Supporting Component Composition

Architecture Description Language (ADL) is one of the keys to software architecture research, but most attention was paid to the description of software structure and high-level analysis of some system properties, while the ability to support refinement and implementation of Software Architecture (SA) models was ignored. In this paper, we present the ABC/ADL, an ADL supporting component composition. Besides the capability of architecting software systems, it provides support to the automated application generation based on SA model via mapping rules and customizable connectors

SDSN@RT: a middleware environment for single-instance multi-tenant cloud applications

With the Single-Instance Multi-Tenancy (SIMT) model for composite Software-as-a-Service (SaaS) applications, a single composite application instance can host multiple tenants, yielding the benefits of better service and resource utilization, and reduced operational cost for the SaaS provider. An SIMT application needs to share services and their aggregation (the application) among its tenants while supporting variations in the functional and performance requirements of the tenants. The SaaS provider requires a middleware environment that can deploy, enact and manage a designed SIMT application, to achieve the varied requirements of the different tenants in a controlled manner. This paper presents the SDSN@RT (Software-Defined Service Networks @ RunTime) middleware environment that can meet the aforementioned requirements. SDSN@RT represents an SIMT composite cloud application as a multi-tenant service network, where the same service network simultaneously hosts a set of virtual service networks (VSNs), one for each tenant. A service network connects a set of services, and coordinates the interactions between them. A VSN realizes the requirements for a specific tenant and can be deployed, configured, and logically isolated in the service network at runtime. SDSN@RT also supports the monitoring and runtime changes of the deployed multi-tenant service networks. We show the feasibility of SDSN@RT with a prototype implementation, and demonstrate its capabilities to host SIMT applications and support their changes with a case study. The performance study of the prototype implementation shows that the runtime capabilities of our middleware incur little overhead

Reconfiguration of legacy software artifacts in resource constraint embedded systems

Hochgradig ressourcenbeschränkte eingebettete Systeme befinden sich überall. Einige dieser Systeme befinden sich in Smart-Phones oder elektronischen Kontroll-Einheiten, andere in Sensor-Netzwerken oder auch Smart-Cards. Gerade die zuletzt genannten gehören zu den in Bezug auf Prozessorleistung und Speicherplatz am meist beschränkten Systemen. Um bei gleicher Ressourcenauslastung mehr Funktionalität bereitzustellen führt diese Arbeit ein Verfahren ein, welche es erlaubt durch Rekonfigurationstechniken dieses Problem zu lösen. Im Gegensatz zu traditionellen Verwendungszwecken von Rekonfigurationstechniken wird in dieser Arbeit Rekonfiguration zur Reduktion der Anwendungsgröße verwendet. Heutige Architekturen, welche Rekonfiguration ermöglichen, basieren auf der Unterstützung dieser Mechanismen auf Entwurfs- bzw. Source-Code Ebene. Software Lösungen basieren jedoch zum großen Teil auf wiederverwertbaren Bibliotheken oder Drittanbieter-Komponenten, welche keine Unterstützung von Rekonfiguration mit sich bringen und zumeist im Binärformat vorliegen. Diese Arbeit stellt eine Methode vor, um ein existierendes System unter Verwendung von Binärcode automatisch in ein rekonfigurierbares System umzuwandeln, mit dem Ziel die Anwendungsgröße zuverringern und dabei weiterhin harten Echtzeitbedingungen zu genügen. Das Verfahren basiert auf der Verwendung von Binärcode-Analyse Techniken zur Rekonstruktion der Anwendungssemantik, welche es erlauben dem Benutzer durch Bedingungen in einer Hochsprache Komponenten aus der Anwendungen zu extrahieren. Diese Komponenten werden anschließend optimiert. Mit dem Verfahren ist es möglich nicht rekonfigurierbare binäre Softwaresysteme in rekonfigurierbare Systeme umzuwandeln, welche die Anwendungsgröße reduzieren und dabei harte Echtzeit-Bedingungen erfüllen.Highly resource-constrained embedded systems are everywhere. Some of them can be found inside smartphones, electronic control units, others in wireless sensor networks or smart cards. The last two systems are among the most restrictive ones in the sense of processing power, energy consumption and memory availability. Pricing policies often lead to a reduction in software functionality as cheaper hardware with less resources is demanded for the final product. In order to allow more complex software to run on such constrained systems, this thesis proposes the use of software reconfiguration. In contrast to traditional uses of reconfiguration this thesis proposes the use of reconfiguration mechanisms in order to reduce the footprint of an deeply embedded application while maintaining real-time constraints. Todays adaptable architectures require the support of reconfigurability and adaptability at design level. However, modern software products are often constructed out of reusable but non-adaptable legacy software artifacts to meet early time-to-market requirements. This thesis proposes a methodology to semiautomatically use existing binaries in a reconfigurable manner. It is based on using binary analysis techniques to reconstruct the semantics of the binary application in order to allow the system developer to select meaningful code parts as components from the binary code. Using a set of high level constraints the user is able to extract components from the binary application. These components are then subject to a design space exploration step, which optimizes the resulting reconfigurable system regarding parameters as, e.g., worst case blocking time and flash lifetime. With this approach, reconfiguration can be added with a low effort to non-adaptive binary software in order to decrease the footprint of the application while maintaining real-time constraints.Tag der Verteidigung: 05.04.2013Paderborn, Univ., Diss., 201