Methods, apparatus, and program products for improved finalization

A computing apparatus configured to reclaim memory referenced by a finalizable-object, said finalizable-object having been instantiated from a class definition incorporating at least one parent class and one or more class-extensions into a class hierarchy;

• the apparatus comprising a memory marking logic configured to mark for retention a related memory reachable from a reference field of said finalizable-object, and a finalization-interface logic configured to add said finalizable-object to a finalization set for subsequent invocation of a non-trivial finalize-method;
• wherein the improvement apparatus to the finalization-interface logic comprises:
• an iteration logic configured to iterate from the ultimate class-extension of said finalizable-object towards the root class of said finalizable-object:
• select an iterated class-extension, said class-extension corresponding to a portion of said finalizable-object that includes said reference field;
• determine whether said class-extension selected by the selection logic has a finalizer-free characteristic;
• in response to determining that said class-extension has a finalizer-free characteristic, mark said related memory for reclamation so that the related memory can be reclaimed by a garbage collection process before an invocation of finalize methods, wherein for any class-extension before a first class-extension without a finalizer-free characteristic, said related memory is marked for reclamation;
• and
• in response to determining that said class-extension does not have a finalizer-free characteristic, mark said related memory for retention, wherein said related memory cannot be reclaimed until after the invocation of said non-trivial finalize-method.

A computer program product comprising:

• a computer-usable data medium providing instructions that, when executed by a computer, cause said computer to perform a method for reclaiming memory referenced by a finalizable-object, said finalizable-object having been instantiated from a class definition incorporating at least one parent class and one or more class-extensions into a class hierarchy;
• the product comprising marking for retention a related memory reachable from a reference field of said finalizable-object, and adding said finalizable-object to a finalization set for subsequent invocation of a non-trivial finalize-method;
• wherein the improvement comprises:
• iterating from the ultimate class-extension of said finalizable-object towards the root class of said finalizable-object:
• selecting an iterated class-extension, said class-extension corresponding to a portion of said finalizable-object that includes said reference field;
• determining whether said class-extension has a finalizer-free characteristic;
• in response to determining that said class-extension has a finalizer-free characteristic, marking said related memory for reclamation so that the related memory can be reclaimed by a garbage collection process before an invocation of finalize methods, wherein for any class-extension before a first class-extension without a finalizer-free characteristic, said related memory is marked for reclamation;
• and
• in response to determining that said class-extension does not have a finalizer-free characteristic, marking said related memory for retention, wherein said related memory cannot be reclaimed until after the invocation of said non-trivial finalize-method.