Chapter 3 Building Structural Diagrams

Associations property sheet Detail tab

Each end of an association is called a role. You can define its multiplicity, persistence, ordering and changeability. You can also define its implementation.

Property Description
Role name Name of the function of the class as viewed by the opposite class
Visibility Specifies the visibility of the association role, how it is seen outside its enclosing namespace. When the role of an association is visible to another object, it may influence the structure or behavior of the object, or similarly, the other object can affect the properties of the association. You can choose between:

  • Private – only to the object itself
  • Protected – only to the object and its inherited objects
  • Package – to all objects contained within the same package
  • Public – to all objects (option by default)
Multiplicity The allowable cardinalities of a role are called multiplicity. Multiplicity indicates the maximum and minimum cardinality that a role can have. You can choose between:

  • 0..1 – zero or one
  • 0..* – zero to unlimited
  • 1..1 – exactly one
  • 1..* – one to unlimited
  • * – none to unlimited


An extended attribute exists for each role of an association. It allows you to choose how the association should be implemented. They are available in your current object language, from the Profile\Association\ExtendedAttributes category, under the 'roleAContainer' and 'roleBContainer' names. Such extended attributes are pertinent only for a 'many' multiplicity (represented by *), they provide a definition for collections of associations.

For more information on the object language, see section Understanding the object language editor, in chapter Object Languages Reference Guide in the Advanced User Documentation .
Array size Specifies an accurate array size when the multiplicity is greater than 1.
Changeability Specifies if the set of links related to an object can be modified once the object has been initialized. You can choose between:

  • Changeable – Associations may be added, removed, and changed freely
  • Read-only – You are not allowed to modify the association
  • Frozen – Constant association


Add-only – New associations may be added from a class on the opposite end of the association
Ordering The association is included in the ordering which sorts the list of associations by their order of creation. You can choose between:

  • Sorted – The set of objects at the end of an association is arranged according to the way they are defined in the model
  • Ordered – The set of objects at the end of an association is arranged in a specific order


Unordered – The end of an association is neither sorted nor ordered
Initial value Lets you type an instruction for initializing migrated attributes, for example 'new client ()'
Navigable Indicates whether or not information can be transmitted between the two objects linked by the relationship
Persistent When selected, specifies that the instance of the association is preserved after the process that created this instance terminates
Volatile Indicates that the corresponding migrated attributes is not a member of the class. It is only defined by the getter and setter operations
Container type Lets you select a container collection for migrated attributes of complex types
Implementation class Lets you select the container implementation
Migrated attribute Name of the migrated association role

For more information on association container and implementation, see section Association implementation.

 

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