The SEDRIS Data Representation Model
APPENDIX A - Classes
Control Link

Abstract Class Name: Control Link

Superclass - <SEDRIS Abstract Base>

Subclasses

Definition

An instance of this DRM class specifies the connection between <Expression> instances and the fields of other DRM objects (termed target objects). For each class of target object, there shall be a specialization of this class to match it. Instances of the specialized subclass shall be aggregated by the target object. The definition of each subclass shall specify how the ordered list of <Expression> instances is used to determine the values of the fields of the target object (termed target fields).

In general, a specialized <Control Link> instance contains at least one field (termed a link field) for each target field in the target object. The link field is an index into the ordered aggregation of <Expression> instances, and is used to select the specific <Expression> instance that controls the value of the target field. The specialization may also contain fields specifying indexes into the ordered aggregation of <Expression> instances. In this case, the referenced expressions are used to constrain the values of the target field.

Primary Page in DRM Diagram:

Secondary Pages in DRM Diagram:

Example

See individual subclasses for examples.

Constraints

Composed of (two-way)

Inherited Field Elements

This class has no inherited field elements.

Field Elements

SE_String description; 1

Notes

Fields Notes

description

The description field specifies a text description of the purpose of the <Control Link> instance.


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Last updated: July 26, 2006 Copyright © 2006 SEDRIS