Association vs Connector - detailed

The specific Connectors printerConnector and cameraConnector are each typed by the same Association USB_Cable, which represents communication between any compatible instances of the USB_Device and USB_Host blocks. The Properties :USB_Printer and :USB_Camera are compatible with USB_Device and the Property :USB_Laptop is compatible with USB_Host.

Note that having more than one Connector of the same Association type is admissable here, because of the multiplicity [0..*] on the property device:USB_Device.

A word on naming

Because the instances of USB_Printer, USB_Camera, and USB_Laptop are unique within the context block ConnectedUsbSystem there is no need to name the corresponding properties owned by that context block, so they remain anonymous consistent with Webel Best Practice.

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Associative BDD view

Notes

[TOOL, WORKAROUND]{SUGGESTED} MagicDraw/Cameo: If you can't find Usage on a particular diagram just use a Dependency then the refactor context menu item.

[WARNING] The difference between Dependency and Usage in UML is notoriously vague.

[ASSERTION, TIP]{STRICT} When dealing with required Interfaces you must use Usage (not Dependency) and it has dedicated "socket" notation.

[NAMING, POLICY]{STRICT} When using acronyms in names of Classifiers either treat them as a word 'TlaLikeThis' or suffix with an underscore 'TLA_LikeThis', except at the end of the name 'LikeThisTLA' is admissable.

[NAMING, POLICY]{STRICT} SysML: Naming: Always use either anonymous or first letter lower case for Property, ObjectNode and InstanceSpecification names; no exceptions (unless using names to "quote text")! Valid: 'lowerCamelCase' OR 'tla' vs TLA acronym OR 'uCC' vs UpperCamelCase

Snippets (quotes/extracts)

[UML-2.5.1] A Dependency is a Relationship that signifies that a single model Element or a set of model Elements requires other model Elements for their specification or implementation.

[UML-2.5.1] This means that the complete semantics of the client Element(s) are either semantically or structurally dependent on the definition of the supplier Element(s).

[UML-2.5.1] A Usage is a Dependency in which the client Element requires the supplier Element (or set of Elements) for its full implementation or operation.