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- Stronger variety of Aggregation
- Part object may belong to only one whole object
- Parts live and die with the whole object
- Any deletion of whole cascades down to parts
- The multiplicity on the whole side must be 0 or one (0..1), but the multiplicity on the part side may be any interval (0..*)
- A composition Aggregation forms a tree of parts.
- 3 Notations: one solid diamond for each part, or one solid diamond as root of the tree of parts, or all parts inside the whole class
Ananda Amatya
11/3/1999