Summary

I l @ ve RuBoard

Relationships provide the conduit for object interaction. Two types of relationships between classes that are discovered during analysis are associations and aggregations. An association is a bidirectional semantic connection between classes. An aggregation is a specialized form of association in which a whole is related to its part(s).

An association may be named. Usually the name is an active verb or verb phrase that communicates the meaning of the relationship. Roles can be used instead of association names . A role name is a noun that denotes the purpose or capacity wherein one class associates with another. Multiplicity is the number of instances that participate in a relationship. There are two multiplicity indicators for each association or aggregation ”one at each end of the relationship line.

Multiple objects belonging to the same class may have to communicate with one another. This is shown on the class diagram as a reflexive association or aggregation.

Scenarios are examined to determine if a relationship should exist between two classes.

Packages are related via dependency relationships. If package A is dependent on package B, this implies that one or more classes in package A initiates communication with one or more public classes in package B.

I l @ ve RuBoard