1. A data processing system, comprising: an enterprise services framework interface adapted to receive a service request from a service consumer; a database storing transactional data; a repository storing public metadata descriptive of business objects and for storing private metadata descriptive of a buffer object, wherein the public metadata is public to the service consumer and the private metadata is private to an enterprise services provider; a processor executing an application program; and a main memory storing an instance of the buffer object, the instance of the buffer object containing the private metadata and at least one instance of one of the business objects, methods for accessing the database using the application program, or methods for calling the application program, wherein: the at least one instance of one of the business objects describes an elementary business process and carries public metadata, the public metadata directly identifying an application program as being called by the at least one instance of one of the business objects in response to the service request; the application program identified by the public metadata carried by the business objects checks transactional data requested by the service consumer and determines whether or not the transactional data is accepted or declined; and in the case that the transactional data requested by the service consumer is accepted by the application program, the buffer object receives an acceptance message from the application program and allows the transactional data to be stored in the database.