1. A system having a processor and a computer-readable storage medium for integrating enterprise information systems, comprising: an application view that provides a layer of abstraction to internal enterprise information system functions by defining a set of business functions, wherein the application view is stored on the computer-readable storage medium; a resource adapter that invokes the internal enterprise information system functions and exposes said internal enterprise information system functions to the application view, wherein J2EE Connector architecture (JCA) provides a standardized approach for the development of the resource adapter, wherein the resource adapter is stored on the computer-readable storage medium; an application integration framework built on top of the JCA to provide a standards-based architecture for hosting the resource adapter, wherein the application integration framework implements a common model on top of the JCA that is focused on business-level concepts; and a common communications protocol that defines events and services encoded as XML documents for communicating with the enterprise information system, said events and services further including: an event initiated by the enterprise information system, said event responding to a particular application state in the enterprise information system, wherein one or more client listeners registered for the event receive data regarding said event when the event is triggered, such that the data is extracted and propagated from the enterprise information system by the application view at the time of the event being triggered in the enterprise information system; and a service that is executed upon receiving a request, wherein service execution causes the application view to invoke at least one of the internal enterprise information system functions.