Browse Prior Art Database

Mechanism for Incorporating Secondary Inheritance in Object-Oriented Systems

IP.com Disclosure Number: IPCOM000106055D
Original Publication Date: 1993-Sep-01
Included in the Prior Art Database: 2005-Mar-20
Document File: 2 page(s) / 93K

Publishing Venue

IBM

Related People

Calo, SB: AUTHOR [+2]

Abstract

Disclosed is a mechanism for an object-oriented system which allows different attributes of a given object to be inherited from other objects (called secondary parents); sets of attributes to be inherited from the same other object (or secondary parent); sets of attributes to continue to be inherited as default values from the parent class of the given object; resolution of the actual attribute value in the secondary parent to be also determined in any appropriate fashion (explicitly, via primary inheritance, or via secondary inheritance); and, dynamic change in the designation of the secondary parent of a set of attribute values.

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Mechanism for Incorporating Secondary Inheritance in Object-Oriented Systems

      Disclosed is a mechanism for an object-oriented system which
allows different attributes of a given object to be inherited from
other objects (called secondary parents); sets of attributes to be
inherited from the same other object (or secondary parent); sets of
attributes to continue to be inherited as default values from the
parent class of the given object; resolution of the actual attribute
value in the secondary parent to be also determined in any
appropriate fashion (explicitly, via primary inheritance, or via
secondary inheritance); and, dynamic change in the designation of the
secondary parent of a set of attribute values.

      In the system, objects are organized into classes and the
structure of an object is determined by the structure of its parent
class.  Classes in turn also have parent classes (called
superclasses) and are arranged in a tree-structured taxonomical
hierarchy (called the primary hierarchy) that supports default value
inheritance as well as structural inheritance.  In addition the
fields that hold the attribute values within an object are organized
into trees.  Groups of fields are associated with substructures that
are in turn associated with other fields and substructures in an
hierarchical arrangement.  One of the fields that is required to be
in every object holds the identity of its primary parent and is
directly associated with the object itself (the root of the
substructure hierarchy).  The substructures designated within the
object are used for directing value inheritance.

      Secondary parent-child relationships can be established by
having a field of the child object designated as a child_of field,
having a field of the parent object designated as a parent_of field,
and having the parent field identify the child object and having the
child field identify the parent object.  The parent field may
identify a list of children in order to establish a one-to-many
relationship.  The child field cannot identify more than one parent,
but one object can have several different child fields, each
identifying a different parent.  This would be the case whenever the
object was involved in several secondary parent-child relationships.

A child_of field would contain information not only identifying the
parent object, but also identifying a particular substructure within
that parent object.  Likewise the parent_of field would identify not
simply a list of child objects, but a list of particular
substructures within those child object...