Aggregation Kind

A Property that is a relation end may carry an aggregationKind. On the whole end of a parthood (part-of) relation it records how the parts relate to the whole, mirroring UML's aggregation and composition diamonds. On any other end it is simply NONE — a plain association end.

This is a closed enumeration: aggregationKind must be one of the three tokens below, or null.

JSON type: string (enum) or null.
Values: COMPOSITE, SHARED, NONE.
Constraint: null is interpreted as NONE.

Values

Value	Meaning	Example
`COMPOSITE`	Parts are exclusive to a single whole (UML filled diamond).	an Engine as composite part of a Car
`SHARED`	Parts may be shared across wholes (UML hollow diamond).	a Person as shared member of Teams
`NONE`	Not a parthood / whole end — a plain association end.	either end of `studies in`

note

null is interpreted as NONE. A relation end with no aggregation semantics may therefore be serialized as either "aggregationKind": "NONE" or "aggregationKind": null.

Example

The whole end of a «componenthood» relation, marking Car as the composite whole of its parts:

{
  "type": "Property",
  "id": "end_car",
  "name": { "en": "car" },
  "stereotype": null,
  "isDerived": false,
  "propertyType": "class_car",
  "cardinality": "1",
  "aggregationKind": "COMPOSITE",
  "isOrdered": false,
  "isReadOnly": false,
  "subsettedProperties": [],
  "redefinedProperties": [],
  "customProperties": null,
  "created": "2024-09-04",
  "modified": null,
  "alternativeNames": [],
  "description": null,
  "editorialNotes": [],
  "creators": [],
  "contributors": []
}

tip

Aggregation kind is most meaningful alongside a parthood relation stereotype such as componenthood, subCollection, subQuantity, or membership.

Values​

Example​

Values

Example