Copy-on-write optimization of immutable objects for objects oriented languages

摘要

A computer implemented method, apparatus, and computer program product for copy-on-write optimization of immutable objects. An immutable object is marked as read-only to form a read-only object. The read-only object is formed to delay copying of the immutable object until a runtime determination is made that a write to the immutable object will be made. In response to an attempt to write to the read-only object, an internal value of the read-only object is copied to read-and-write storage using runtime information to form a writable copy of the read-only object. A set of references for the read-only object is updated to point to the writable copy of the read-only object. Delaying copying of the immutable object optimizes a copy-on-write of the immutable object.