Finally, we began with the following specific task objectives. We succeeded, however, only in making a reasonable list of core concepts, providing partial definitions and explanations, and exposing some of the subtleties. The remainder of the report documents our results. Hermann Kaindl, Frederick Kohun, Barry Kurtz, Steve Liddle, Jim Rumbaugh, Robert Skovira. Private memory consists of an object's identifier and an object's state, which can be characterized by the values of its attributes.
Operations constitute the services an object can provide.
But from a design or implementation point of view, it may be useful to distinguish objects that can only be represented by an object identifier and those that can be represented by a lexicalized incarnation of themselves. Objects have properties, including identity, state, behavior, lifetime, and boundary. From an analysis point of view, identity can be thought of as an intrinsic property of an object that makes it recognizable and distinguishable from other objects. In an implementation, the identity can be explicitly represented as an object identifier, but this may be unnecessary if the attributes or relationships are sufficient to identify the object for all time. Lifetime is the period of time during which an object exists.