Abstract not found

We present the basic principles and possible applications of systems capable of meta-reasoning and reflection. After a discussion of the seminal approaches, we outline our own perception of the state of the art, mainly but not only in computational logic and logic programming. We review relevat successful...

Abstract. Although widely used in software engineering, metaprogramming is often misunderstood. The researchers often disagree what concepts characterize metaprogramming. The concepts of metaprogramming are often used without acknowledging the usage of metaprogramming itself. We overview the examples and definitions of metaprogramming in computer science, identify, describe and discuss the fundamental concepts of metaprogramming (code generation, transformation, reflection, generalization, metaprogram, metadata, level of abstraction and separation of concerns). We analyze their relationship and present taxonomy, based on a study of sources on metaprogramming.

Computational reflection provides the developers with a programming mechanism devoted to favorite code extensibility, reuse and maintenance. Notwithstanding that, it has not achieved developers’ unanimous acceptance and its full potential yet. In our opinion, this depends on the intrinsic complexity of most of the reflective approaches that hinders their efficient implementation. The aim of this paper consists of defining the essence of reflection, that is, to identify the minimal set of characteristics that a software system must have to be considered reflective. The consequence is the realization of a run-time environment supporting the essence of reflection without affecting the programming language and with a minimal impact on the programming system design. This achievement will improve reflective system performances reducing the impact of one of the most diffuse criticism about reflection: low performance. Keywords: Reflection, Run-Time Environment, Compiler Construction. 1.

Abstract. Although current programming models provide adequate performance, many prove inadequate to support the effective development of efficient Grid applications. Many of the hard issues, such as the dynamic nature of the Grid environment, are left to the programmer. We are developing a programming model that incorporates a familiar, formal computational model and a reflective interface. The programming model, called PAGIS, provides a desirable abstract computer with an interface to introduce and customize Grid functionality. Using PAGIS, an application programmer constructs applications that are implicitly parallel and distributed transparently. This paper describes the basic components of the PAGIS framework for constructing and executing applications, and the reflective techniques to customize applications for computation on the Grid. 1

Service-based systems that are dynamically composed at run time to provide complex, adaptive functionality are currently one of the main development paradigms in software engineering. However, the Quality of Service (QoS) delivered by these systems remains an important concern, and needs to be managed in an equally adaptive and predictable way. To address this need, we introduce a novel, tool-supported framework for the development of adaptive service-based systems called QoSMOS (QoS Management and Optimisation of Service-based systems). QoSMOS can be used to develop service-based systems that achieve their QoS requirements through dynamically adapting to changes in the system state, environment and workload. QoSMOS service-based systems translate high-level QoS requirements specified by their administrators into probabilistic temporal logic formulae, which are then formally and automatically analysed to identify and enforce optimal system configurations. The QoSMOS self-adaptation mechanism can handle reliability- and performance-related QoS requirements, and can be integrated into newly developed solutions or legacy systems. The effectiveness and scalability of the approach are validated using simulations and a set of experiments based on an implementation of an adaptive service-based system for remote medical assistance.

In this paper, we describe the results of an experiment to add support for multimethod communication to the Nexus-Java communications library using metalevel programming techniques. We describe the Nexus architecture and the Java implementation of this architecture. We summize the technique of metalevel programming, and apply the technique to develop a metalevel for adaptive multimethod communication called Gekko. In addition, we discuss the test environment we use for evaluation of Gekko, and discuss lessons we have learnt in its development.

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