MJSContainersDoc.tioga
Last tweaked by Mike Spreitzer on September 21, 1989 3:16:23 pm PDT
MJSContainers
CEDAR 7.0 — FOR INTERNAL XEROX USE ONLY
MJSContainers
The right Containers
Mike Spreitzer
© Copyright 1989 Xerox Corporation. All rights reserved.
Abstract: MJSContainers is Containers done right. The biggest sin of Containers is that it doesn't allow further subclassing with decent inheritence.
Created by: Mike Spreitzer
Maintained by: Mike Spreitzer <Spreitzer.pa>
Keywords: Containers
XEROX Xerox Corporation
Palo Alto Research Center
3333 Coyote Hill Road
Palo Alto, California 94304
For Internal Xerox Use Only
1. What and Why
Viewers is object-oriented; one can even set up a single-inheritence sublcass hierarchy without too much trouble. Unfortunately, Containers blows it. For example, it doesn't provide a place for subclasses to hang their instance data. It also prevents subclasses from providing many interesting class procedures.