Multiplicity

In class diagrams, multiplicity specifies the range of allowable cardinalities that a set of associated classes can assume.

A multiplicity specification is a subset of the open set of non-negative integers. You can give multiplicity specifications for roles in association relationships.

A multiplicity relationship appears as a text string that comprises an integer value that represents the number of data objects that can be associated with a C/C++ class.

Multiplicity relationships are possible in that one class can relate to another in a one-to-one or a one-to-a bounded interval; for example, 1 to 1 or 1 to 10.

Multiplicity relationships are the number of objects from one class that relate to a single object in an associated class. As the following figure illustrates, to represent these numbers in a class diagram, multiplicity relationships are shown close to the association line (connector) near the associated class.

A C/C++ multiplicity relationship is displayed.

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