What is Higher-Order

Component-based approaches generalize basic object-oriented implementations by allowing large collections of objects to be grouped together and externalized in terms of public interfaces. A typical component-based system will include a large number of interacting components. Service-Oriented Architecture (SOA) organizes a system in terms of components that communicate via services. Components publish services that they implement as business processes. Consequently, a change to a single component can have a ripple effect on the service-driven system. Component reconfiguration is motivated by the need to evolve the component architecture and can take a number of forms. The authors define a dynamic architecture as one that supports changing the behavior and topology of existing components without stopping, updating, and redeploying the system. This chapter addresses the problem of dynamic reconfiguration of component-based architectures. It proposes a reification approach that represents key features of a language in data, so that a system can reason and dynamically modify aspects of it. The approach is described in terms of a new language called µLEAP and validated by implementing a simple case study.