Dalila Tamzalit

Extraction of Component-Based Architecture from Object-Oriented Systems

Software architecture modeling and representation became a main phase of the development process of complex systems. In fact, software architecture representation provides many advantages during all phases of software life cycle. Nevertheless, for many systems, like legacy or eroded ones, there is no available representation of their architectures. In order to benefit from this representation, we propose, in this paper, an approach called ROMANTIC which focuses on extracting a component-based architecture of an existing object-oriented system. The main idea of this approach is to propose a quasi-automatic process of architecture recovery based on semantic and structural characteristics of software architecture concepts.

Guiding Architectural Restructuring through Architectural Styles

Software architectures constitute one of the main artefacts of software-intensive system development. They outline the essential components and interconnections of a software system at a high level of abstraction, ignoring unnecessary details. How to address the evolution of software architectures, however, is still an important topic of current research. In this article, we use UML 2 as architectural description language notation and formalise it with graph transformation, with a proof-of-concept implemented in the AGG tool. We use this formalisation to express and reason about architectural evolution patterns that introduce architectural styles.

Evolution Shelf: Reusing Evolution Expertise within Component-Based Software Architectures

Despite that reuse libraries are now well adopted during software development step, software evolution step is not yet covered by this kind of beneficial approach. In this paper we present the evolution shelf, a generic infrastructure to achieve for-reuse and by-reuse techniques within the field of software evolution. The basic idea behind that is to propose and encourage the reuse of recurring and reliable evolution expertises to achieve the structural evolution of a software system at the architectural level. For that purpose, the shelf assists architects in classifying, storing and selecting reusable architectural evolution operations. The underlying concept that we propose to capitalize the expertises is called evolution style and it mixes a syntactic and a semantic description format. These ideas form a core for a long-term vision in which it is possible to build a business model of evolution-of-the-shelf (EOTS) with the special objective to decrease the efforts and the risks related to the evolution activities.

A unified approach for software architecture evolution at different abstraction levels

This paper presents a model for software architecture evolution, called SAEV (software architecture evolution model). A software architecture is defined through its architectural elements (components, connectors, configurations ..). We associate to these architectural elements three abstraction levels namely from the most abstract one: the meta level, the architectural level and the application one. SAEV offers a whole of concepts, which are evolution operations, evolution rules, evolution strategies and invariants, to describe and manage uniformly the evolution of architectures at the architectural level as well as at the application level. This is done independently of any description or implementation language. In addition, SAEV offers a uniform mechanism to carry out a given evolution at these different levels.

Variability as a service: outsourcing variability management in multi-tenant saas applications

In order to reduce the overall application expenses and time to market, SaaS (Software as a Service) providers tend to outsource several parts of their IT resources to other services providers. Such outsourcing helps SaaS providers in reducing costs and concentrating on their core competences: software domain expertises, business-processes modeling, implementation technologies and frameworks etc. However, when a SaaS provider offers a single application instance for multiple customers following the multi-tenant model, these customers (or tenants) requirements may differ, generating an important variability management concern. We believe that variability management should also be outsourced and considered as a service. The novelty of our work is to introduce the new concept of Variability as a Service (VaaS) model. It induces the appearance of VaaS providers. The objective is to relieve the SaaS providers looking forward to adopt such attractive multi-tenant solution, from developing a completely new and expensive variability solution beforehand. We present in this paper the first stage of our work: the VaaS meta-model and the VariaS component.

Evolution styles to the rescue of architectural evolution knowledge

The core idea is to consider software-architecture evolution tasks as a knowledge that must be clearly modeled and properly managed. The main expected benefit is the reuse of existing and already available evolution expertise rather than reinventing it, sometimes awkwardly and thus avoid time-consuming redundant evolution activities. For this purpose, we propose to use the evolution style concept as a neutral interchange format to capitalize and transfer knowledge about domain-specific evolution tasks. In this paper we put the focus on how it is possible to reason on evolution-styles description libraries through a classification scheme. Specifically, we present the evolution shelf, an infrastructure to perform (a) incremental acquisition of new evolution descriptions and (b) retrieval of evolution descriptions matching with a given context. Our shelf, dedicated to software architects, relies on well-known repository techniques while updating them to support and exploit the evolution-style concept.

Quality-Driven Extraction of a Component-based Architecture from an Object-Oriented System

Software architecture modeling and representation became a main phase of the development process of complex systems. In fact, software architecture representation provides many advantages during all phases of software life cycle. Nevertheless, for many systems, like legacy or eroded ones, there is no available representation of their architectures. In order to benefit from this representation, we propose, in this paper, an approach called ROMANTIC which focuses on extracting the architecture of an object-oriented system. The main idea of this approach is to propose a quasi-automatic process of architecture recovery based on the quality characteristics of an architecture by formulating it as a search-based problem. This last acts on the space composed of all possible architectures abstracting the object-oriented system.

Search-Based Extraction of Component-Based Architecture from Object-Oriented Systems

Software architecture modeling and representation are a main phase of the development process of complex systems. In fact, software architecture representation provides many advantages during all phases of software life cycle. Nevertheless, for many systems, like legacy or eroded ones, there is no available representation of their architectures. In order to benefit from this representation, we propose an approach called ROMANTIC which focuses on extracting a component-based architecture of an existing object-oriented system. This approach considers this problem as a balancing problem of competing constraints which aims to select the best solution among all the possible architectures. Consequently, we present in this paper the identified constraints of this problem and its formulation as a search-based problem.

Decoupling variability management in multi-tenant SaaS applications

Variability represents an important challenge in multi-tenant SaaS applications. In fact, even if multi-tenancy realizes SaaS providers dream of having a single maintained software instance serving multiple customers (tenants) for common functionality, variations in tenants needs and their specific requirements at many places of the application bring providers back to the real world. They face an additional design concern: supporting application variability on a pertenant basis. In this paper, we focus on such variability concern and try to reduce its complexity by decoupling its management through different application layers. We rely on a two-steps decoupling approach: the first step consists of representing application variations as an explicit variability model while the second step consists of choosing the must appropriate application layer(s) to manage each variation. Our approach is illustrated by relying on a case study from the food industry.

Adaptation patterns for service based inter-organizational workflows

The SOA (Service Oriented Architecture) paradigm provides important advantages like interoperability, reusability and flexibility required in the area of business applications. In our research works, we focus on the use of SOA to implement inter-organizational workflows (IOWF). Our goal is to obtain IOWF models flexible enough in order to ease their adaptation at build-time and at runtime, because services are loosely coupled components, easily invoked and interoperable. This paper focuses on specific and well common IOWF-architectures defined in the literature; it deals with adaptation of IOWF process models obeying to these architectures. First, we define the concept of Service-Based Cooperation Pattern (SBCP) that supports service-based IOWF models meeting one of the specific architectures considered. Then, we state a set of recurrent operations of adaptation (attached to process and interaction aspects) that can be applied on service-based IOWF models, and we illustrate their implementation for IOWF models specified with BPEL.