Class Descriptions

Inside Macintosh: OpenDoc Class Reference /: Preface - About This Book

Class Descriptions
Class descriptions in this book are in alphabetical order. Each class description states how the class is to be used--whether the class can be subclassed, how objects of the class are created, and how a part can use an object of the class. If a class is not used directly by parts but only by the OpenDoc document shell or a container application, the class description makes this restriction clear.

Abstract Superclasses
This book and other OpenDoc manuals use the term abstract superclass to describe a class, such as ODPersistentObject (page 555), that must be subclassed rather than used directly. In some cases, a superclass is not abstract, but implements basic functionality that can be further extended through subclassing. In the case of ODTransform (page 762), for example, parts can create and use objects of the superclass and need not implement subclasses.

Inheritance Relationships
The ODObject class (page 439) is the root of the OpenDoc class hierarchy. The OpenDoc Programmer's Guide for the MacOS contains illustrations that show the entire OpenDoc class hierarchy. In this book, each class description shows the location of the class in the OpenDoc class hierarchy by listing its ancestors and its subclasses.
The ancestors of a given class are shown as a path up the class hierarchy beginning with the immediate superclass of the class being described and ending with ODObject. An arrow points from each ancestor class in the branch to its immediate superclass. For example, the following branch appears in the class description of ODDocument (page 132). The branch indicates that ODRefCntObject is the superclass of ODDocument and ODObject is the superclass of ODRefCntObject.

Superclasses
ODRefCntObject --> ODObject
The subclasses of a given class are shown as a comma-separated list in alphabetical order. For example, the following list appears in the class description of ODNameSpace (page 428); it indicates that ODNameSpace has two subclasses, ODObjectNameSpace and ODValueNameSpace.

Subclasses
ODObjectNameSpace, ODValueNameSpace
Only immediate subclasses are shown; if you are interested in descendant classes at lower levels in the hierarchy, you can refer to the descriptions of the subclasses or to the diagram in the Programmer's Guide.