The Copy relationship | Webel IT Australia

Gallery

Tutorial

TRAIL: Webel's ultimate guide to Systems Modeling Language (v1) with MagicDraw/Cameo

Section

16:01: Requirements engineering in SysML

Tags and keywords

SysML keywords

Copy

AbstractRequirement::text

AbstractRequirement::/master

Keywords

primary/replica

Slide kind

SysML Requirement Diagram

The Copy relationship enables reuse of a Requirement from a read-only library and reuse of a child Requirement that is owned by a parent composite requirement (a.k.a. compound requirement):

Click on the image to view it full size

SysML-1.6: 'A Copy relationship is a dependency between a supplier requirement and a client requirement that specifies that the text of the client requirement is a read-only copy of the text of the supplier requirement.'

This is useful, for example, for "importing" a Requirement from a read-only model library of a Requirements to be used across multiple projects (such as a library of requirements from a building code).

And if you need to reuse a child Requirement from a composite requirement, you can make a Copy and make that a child of another composite requirement.

A minor tool warning:

MagicDraw/Cameo: Does not copy identical text from a supplier Requirement to a client Requirement on application of the Copy relationship (but DOES offer to fix it when the validation engine warning fires).

Validation engine to the rescue!

It's well known that you just "can't get no ... satisfaction" in requirements engineering unless you can easily see which requirements have or have not been satisfied, so we'll explore next how to use the Satisfy Requirement Matrix.

Up next

MagicDraw/Cameo: Satisfy Requirement Matrix: Hybrid SUV vs Block (all)

Notes

[PROPOSAL] Webel has suggested primary/replica as an alternative to master/slave terminology for the SysML Copy relationship in future SysML versions

[CAVEAT, TOOL] MagicDraw/Cameo: Does not copy identical text from a supplier Requirement to a client Requirement on application of the Copy relationship (but DOES offer to fix it when the validation engine warning fires).

[TIP] The SysML Copy relationship can be used to "import" Requirements from an existing read-only library into a new project context.

Snippets (quotes/extracts)

[SysML-1.6] The use of namespace containment to specify requirements hierarchies precludes reusing requirements in different contexts since a given model element can only exist in one namespace.

[SysML-1.6] A Copy relationship is a dependency between a supplier requirement and a client requirement that specifies that the text of the client requirement is a read-only copy of the text of the supplier requirement.

[SysML-1.6] A Copy dependency created between two requirements maintains a master/slave relationship between the two elements for the purpose of requirements re-use in different contexts

[SysML-1.6] When a Copy dependency exists between two requirements, the requirement text of the client requirement is a read-only copy of the requirement text of the requirement at the supplier end of the dependency.

[SysML-1.6] Copy::1_source_and_taget_are_requirements A Copy dependency may only be created between two NamedElements that have a subtype of the abstractRequirement stereotype applied