Multifaceted object modeling with roles: A comprehensive approach

Abstract

In conventional object-oriented database systems, it is assumed silently that fundamental object types and inter-object relationships can be classified statically, prescribing basic structural and behavioral properties for all the objects in the database. Such a classification-based approach falls short of supporting emerging data-intensive applications requiring more advanced dynamic capabilities. One of such advanced capabilities is the support of modeling subjectivity – the ability to (among others) provide multiple perspectives of application objects or to model so-called `multifaceted objects' which, on different stages, can exhibit different forms and behavior. This article describes an extended object-oriented approach that we have been investigating for this purpose. Advanced features embodied by dynamic and versatile role facilities have been introduced into a conventional object-oriented model, which facilitates specifying and modeling such applications in a natural, incremental and systematic way. Examples from automated manufacturing systems have been used to examine the necessity and utility of such advanced role facilities, and experimental prototype systems of the role mechanism have also been developed by exploiting different techniques and approaches of implementing roles.