Abstract. We present our policy-based middleware, called Manageable and Adaptive Service Compositions (MASC), for dynamic self-adaptation of Web services compositions to various changes. MASC integrates and extends our earlier middleware called the Web Services Message Bus (wsBus). In particular, we discuss MASC support for customization of Web services compositions to address business exceptions and wsBus support for correction (fault management) of Web services compositions to improve reliability. We have evaluated the former support on a stock trading case study and the latter support on a supply chain management case study. Our solutions are complementary to the existing approaches and provide: coordination of fault management between SOAP messaging and business process orchestration, greater diversity of monitoring and control constructs, specification of both technical and business aspects used for adaptation decisions, higher level of abstraction easier for use by non-technical people, and externalization of monitoring and adaptation actions from definitions of business processes.

Evolution of software architectures is, different from architectural design, an area that only few tools have covered. We claim this is due to the lack of support for an important concept of architectural evolution: the notion of architectural design decisions. The absence of

Dynamic architectural change is defined as the addition and removal of components and connectors. Dynamic software architectures are those architectures that modify their architecture and enact the modifications during the system’s execution. This behavior is most commonly known as run-time evolution or dynamism. As dynamic software architecture use becomes more widespread, it is important to gain a better understanding of this type of software evolutionary change and be able to classify formalisms, approaches and tools. Current evaluations in the areas of software architecture and evolutionary change have made strides in classification but are not sufficient to evaluate dynamic software architectures. A dedicated comparison of dynamic software architectures and architectural formalisms is necessary in order to gain a deeper understanding of run-time evolution. In this paper we present a set of classification criteria for the comparison of dynamic software architectures based on: change type, change process, and change infrastructure. We demonstrate the use of the criteria by classifying three types of dynamic software architectural change. In addition we survey 14 current approaches to the formal specification of dynamic software architectures based on graphs, process algebras, logic, and other formalisms. We then

Abstract. In this paper, we have briefly analyzed the aspect-oriented approach with respect to the software evolution topic. The aim of this analysis is to highlight the aspect-oriented potentiality for software evolution and its limits. From our analysis, we can state that actual pointcut definition mechanisms are not enough expressive to pick out from design information where software evolution should be applied. We will also give some suggestions about how to improve the pointcut definition mechanism.

The principal aim of this paper is to apply the Taxonomy of Software Evolution, developed by Mens et. al [1], to position various software tools that support the activity of software refactoring as part of the evolutionary process. This taxonomy is based on the mechanisms of change and the factors that impact upon these mechanisms. The goal of this taxonomy is to position concrete tools and techniques within the domain of software evolution, so that it becomes easier to compare and combine them. In this paper, we apply the taxonomy to four tools that provide explicit support for refactoring. The tools that were considered for this detailed study are the following: Smalltalk VisualWorks 7.0 [2], Eclipse 2.0 [3], Guru (for SELF 4.0) [4] and the Together ControlCenter 6.0 [5]. After a detailed discussion and comparison of these tools, we analyse the strengths, weaknesses and limitations of the evolution taxonomy that was used.

In order to survive in todays highly dynamic marketplace, companies must show a continuous and ever-increasing ability to adapt. Surviving means keeping ahead of or at least keeping up with the competition. This is not only done

Development and deployment via components offers the possibility of prolific software reuse. However, to achieve this potential in a component-rich environment, it is necessary to recognize that component deployment (and subsequent composition) is closer to a continual process than a one-off operation. This is due to the requirement that newly-evolved components need to replace their ancestors in a timely and efficient manner at the client deployment sites. Modern runtime systems which employ dynamic link-loading mechanisms can permit such dynamic evolution. We review the capabilities of several alternative runtime environments to establish some requirements for dynamic evolution. Then we describe a tool designed to support developers and administrators in the migration of component updates within the Microsoft .NET framework.

This position paper identifies emerging trends in refactoring research, and enumerates a list of open questions, from a practical as well as a theoretical point of view. We suggest these directions for further research based on our own experience with refactoring, as well as on a detailed literature survey on software refactoring.

Lab on Re-Engineering

Abstract — We review the definition of evolvability as it appears on the literature. In particular, the concept of software evolvability is compared with other system quality attributes, such as adaptability, maintainability and modifiability.