Class Name: SDRM Class Summary Item

Superclass - Base Summary Item

Definition

Used as part of a summary of a transmittal's content by representing a class that is used within the transmittal.

SDRM Class Summary Items are combined together to form a list of the classes that are used in a transmittal or part of a transmittal. Each such list has only one entry per class. However, it does not have to be a complete list of every class used, and it can include abstract classes.

Each SDRM Class Summary Item can optionally have a list of EDCS Use Summary Items giving the classifications that are attached to objects of that class in the transmittal. Obviously this only makes sense for those classes that can have classification information.

Each SDRM Class Summary Item can also have a list of Spatial Reference Frame Summaries giving the spatial reference frames defined in the transmittal by objects of that class. Obviously this only makes sense for those object types that contain spatial reference frame definitions.

Primary Page in DRM Diagram:

• 20

Example

1. A summary of the object types used in an entire transmittal.
   

2. A summary of object types used in part of a transmittal. (See the FAQ list also).

FAQs

Why is the Union of Primitive Geometry in Example #2 a SDRM Class Summary Item rather than a Hierarchy Summary Item?

This illustrates the possible use of SDRM Class Summary Item if we were to use the Hierarchy Summary Item to show only the top level hierarchy (for some reason).

The data producer may decide, for a number of reasons, that it would be useful to summarize the hierarchy down to a certain level only, but that it's also useful to show that there are aggregates such as Union of Primitive Geometry below that level - i.e., showing that they exist, rather than showing their position in the hierarchy, is what is of value.

Hey! The examples for SDRM Class Summary Item show Polygons and Vertices as SDRM Class Summary Items, but the examples for Primitive Summary Item show them as Primitive Summary Items! Isn't this ambiguous? What's going on?

This isn't ambiguous as the two classes (SDRM Class Summary Item and Primitive Summary Item summarize different aspects of a transmittal. Therefore the same classes can (and will) quite legitimately be represented by both. So Polygon and Vertex can turn up as types of SDRM Class Summary Items, to summarize their presence in the transmittal, and as Primitive Summary Items, to show common patterns of objects in which they are used.

Constraints

Composed of (one-way metadata)

• optionally, some Spatial Reference Frame Summaries

Composed of (two-way metadata)(inherited)

• optionally, some EDCS Use Summary Items (notes)

Component of (two-way)

• optionally, some Hierarchy Summary Items (notes)
• optionally, a Transmittal Summary (notes)

Inherited Field Elements

Notes

Composed of Notes

EDCS_Use_Summary_Item

 Classification(s) used by an objects of the
 specified type, somewhere in the transmittal

Component of Notes

Hierarchy_Summary_Item

 Representing classes used in part of the
 transmittal

Transmittal_Summary

 Representing classes used in the entire
 transmittal

Fields Notes

type

 The DRM class of the object represented by the summary item.