Component adaptation for event-based application integration using active rules

Enterprise applications integrate information and applications in a distributed, networked environment to develop a global application of interconnected components and applications. This paper presents the design and implementation of the wrappers generated to adapt components to a middleware environment that employs active rules to build an enterprise application using an event-driven approach to integrating distributed black-box components. The components adapted in this implementation are based on the Enterprise JavaBeans component model. An application integrator declares the components to be integrated, and may define additional attributes, relationships, and events to be used in the integration process. The metadata for the components to be integrated is used to adapt and enhance the black-box components through the use of wrappers. The wrappers act as a proxy to the black-box component. The adaptation of the wrappers provides for the storage of additional properties for component instances and for the detection of events within the components to generate event notifications. The wrappers are automatically generated from the component metadata using the Extensible Stylesheet Language. The design and implementation of the wrappers establishes a framework that supports an active approach to component-based software integration.