METHOD AND APPARATUS FOR CREATING DYNAMIC ROLES WITH SYSTEM OBJECT MODEL

PROVIDING DYNAMIC ROLES FOR OBJECTS IN AN OBJECT-ORIENTED PROGRAMMING ENVIRONMENT. A MECHANISM ADDS ROLES DYNAMICALLY FOR AN OBJECT DEPENDING ON THE CONTEXT OF THE OBJECT. THE IBM SYSTEM OBJECT MODEL (SOM) IS THE PRINCIPAL BUILDING BLOCK FOR PROVIDING THIS FUNCTION. THE DISPATCH RESOLUTION OF THE SOM IS USED TO PROVIDE THE FUNCTIONS OF THIS INVENTION THE "SOMDISPATCH" METHODS FEATURE. THE "SOMDISPATCH" METHODS IS OVERRIDDEN IN NEW CLASSES TO IMPLEMENT APPLICATION SPECIFIC DISPATCH MECHANISM. DYNAMIC OBJECTS ARE REPRESENTED .AS LISTS OF OBJECTS WHERE OBJECTS ARE ADDED TO THE LIST AT ANY TIME. FOR EXAMPLE, WHEN A PROGRAM IS STARTED, A PERSON OBJECT WILL ONLY HAVE A STUDENT OBJECT. BEFORE CALLING A FUNCTION REQUIRING TEACHER CHARACTERISTICS, THE TEACHER ROLE IS ADDED TO THE PERSON OBJECT. WHEN THE FUNCTION CALL RETURNS, THE TEACHER ROLE IS DELETED FROM THE PERSON OBJECT IF THE ROLE IS NO LONGER NEEDED.FIGURE 9