Process Patterns for Component-Based Software Development

Abstract. Component-Based Development (CBD) has been broadly used in software development, as it enhances reusability and flexibility, and reduces the costs and risks involved in systems development. It has therefore spawned many widely-used approaches, such as Commercial Off-The-Shelf (COTS) and software product lines. On the other hand, in order to gain a competitive edge, organizations need to define custom processes tailored to fit their specific de-velopment requirements. This has led to the emergence of process patterns and Method Engineering approaches. We propose a set of process patterns commonly encountered in component-based development methodologies. Seven prominent component-based method-ologies have been selected and reviewed, and a set of high-level process patterns recurring in these methodologies have been identified. A generic process framework for component-based development has been proposed based on these process patterns. The process patterns and the generic framework can be used for developing or tailoring a process for producing component-based systems

Symmetry and Symmetry Breaking in Software Patterns

Software patterns draw on the work of the architect Christopher Alexander, which in turn builds on foundations that may be more suitable to software than the architectural metaphors themselves. Patterns have a longstanding identity in the scientific community as results of a phenomenon called symmetry breaking. Symmetry breaking can be defined formally in terms of group theory. We establish formal group-theoretic foundations for several object-oriented programming models and show, by formal constructs and by analogy to other fields, that software patterns reduce to symmetry breaking. Such formalisms may be useful as a foundation for pattern taxonomies, and to differentiate patterns as a design discipline from heuristics, rules, and arbitrary microarchitectures

Symmetry in Class and Type Hierarchy

The class concept is central in OO programming (OOP) to implement abstract data types and enforce encapsulation. Type hierarchy has been regarded as a useful technique for consistency during extension. Yet, the importance of class and type hierarchy extends beyond their technical merits. Specifically, a class classifies objects and a type hierarchy classifies classes. Classification is fundamental to design, and its place in program evolution and programming language structure can be elucidated through formal symmetry models. Symmetry is the interplay between an invariant and the possibility of change. This paper discusses the importance of classification in OOP and shows the connection between classification and symmetry in class and type hierarchies

Optimizing Object-Oriented Languages through Architectural Transformations

Certain features of the object-oriented paradigm are a serious impediment for the runtime performance of object-oriented programs

Semantic Web Technologies for the Integration of Learning Tools and Context-Aware Educational Services

Abstract. One of the main software engineers ’ competencies, solving software problems, is most effectively acquired through an active examination of learn-ing resources and work on real-world examples in small development teams. This obviously indicates a need for an integration of several existing learning tools and systems in a common collaborative learning environment, as well as advanced educational services that provide students with right in time advice about learning resources and possible collaboration partners. In this paper, we present how we developed and applied a common ontological foundation for the integration of different existing learning tools and systems in a common learning environment called DEPTHS (Design Patterns Teaching Help System). In addition, we present a set of educational services that leverages semantic rich representation of learning resources and students ’ interaction data to recom-mend resource relevant for students ’ current learning context