Abstract: A method for memory reclamation for object-oriented program-controlled systems with real-time constraints. Resource reclamation, commonly called garbage collection, in object-oriented systems is segmented into discrete, real-time bounded segments. Scheduling of the segments is controlled so that garbage collection is unobtrusive to the system, while memory resources are reclaimed at approximately the same rate as they are allocated. Objects referenced from other objects are checked via an incremental mark/sweep method. Objects referenced from stacks are also accounted for. If a stack cannot be swept for object references in one real-time segment, the stack is copied into a save area and swept during one or more subsequent real-time segments.

Abstract: In object-oriented systems, non-memory resources are both managed by objects and represented as objects. If an object managing or representing non-memory resources becomes unreferenced, the non-memory resources managed by that object are lost from the system. This invention provides, as a part of a garbage collection process that automatic recovers memory resources of unreferenced objects, a last-will method that is invoked for unreachable objects that have provided a method named "finalize." All unreachable objects that have a last will method are put on a list. A separate process is scheduled to run each last-will method on its object in the list. Objects that have become reachable as a consequence of the last-will method are preserved. The memory resources associated with objects that have remained unreachable after the execution of the last-will method are recovered. In this way both memory and non-memory resources are preserved for re-use.