Persistent Active Type Station4 Supertype

Object-oriented database systems are being proposed as the next-generation database technology|especially for so-called non-standard application domains. However, we have argued in an earlier paper [13] that the conventional object paradigm falls short of providing adequate support for such complex application domains as Computer-Integrated Manufacturing (CIM). Today's object-oriented data models still adhere to the conventional procedure invocation execution model. This leads to entirely passive objects whose behavioral pattern is dictated by outside requests under the single-thread-of-control paradigm. Very often, the result is a rather \unnatural" model of complex applications, e.g., CASE and CIM, because the multitude of tasks that are executed in parallel in such distributed application environments has to be forced into a single control ow. We propose to bridge the gap between reality and the informational model by a model of autonomous objects that communicate with each other by \true" message passing. In this paper we present language concepts that enhance the (conventional) object paradigm towards object autonomy and attempt a ( rst) validation based on modelling a sample factory.