Evolving Object Specifications

The notion of object evolution covers several aspects being important for object-oriented information systems. An object keeps its identity (and some of its properties, of course) while changing its external interface and the implementation of its methods. We present a framework based on a temporal logic where the specification of an object template may be modified during system runtime. The presented extended temporal logic dyOSL explicitly manipulates state-dependent sets of current axioms. This framework can handle several problems arising with object evolution. 1 Introduction Conceptual modeling of information systems has successfully adopted the object paradigm as foundation for modeling techniques. However, many approaches are based on more or less informal frameworks influenced by object-oriented analysis and design [Boo91, CY90, RBP + 90]. But the aim of the conceptual modeling process is an exact and unambiguous, i.e. formal, description of the Universe of Discourse. Only a..