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Class UML 2.5::Extend


A relationship from an extending UseCase to an extended UseCase that specifies how and when the behavior defined in the extending UseCase can be inserted into the behavior defined in the extended UseCase.

Direct Superclasses: NamedElement, DirectedRelationship

Direct Subclasses:

Class Precedence List: Extend, NamedElement, DirectedRelationship, Relationship, Element


condition : Constraint (0 1); -- source Extend
extendedCase : UseCase (1 1); -- source Extend

The UseCase that is being extended.

extension : UseCase (1 1); -- source Extend

The UseCase that represents the extension and owns the Extend relationship.
Subsets: DirectedRelationship.source, NamedElement.namespace
Opposite: UseCase.extend

extensionLocation : ExtensionPoint (1 *); -- source Extend

An ordered list of ExtensionPoints belonging to the extended UseCase, specifying where the respective behavioral fragments of the extending UseCase are to be inserted. The first fragment in the extending UseCase is associated with the first extension point in the list, the second fragment with the second point, and so on. Note that, in most practical cases, the extending UseCase has just a single behavior fragment, so that the list of ExtensionPoints is trivial.

clientDependency : Dependency (0 *); -- source NamedElement
name : String (0 1); -- source NamedElement

The name of the NamedElement.

nameExpression : StringExpression (0 1); -- source NamedElement
namespace : Namespace (0 1); -- source NamedElement

Specifies the Namespace that owns the NamedElement.
Derived union with sources: (extension)
Subsets: Element.owner
Opposite: Namespace.ownedMember

qualifiedName : String (0 1); -- source NamedElement
visibility : VisibilityKind (0 1); -- source NamedElement
source : Element (1 *); -- source DirectedRelationship

Specifies the source Element(s) of the DirectedRelationship.
Derived union with sources: (extension)
Subsets: Relationship.relatedElement

target : Element (1 *); -- source DirectedRelationship
relatedElement : Element (1 *); -- source Relationship
ownedComment : Comment (0 *); -- source Element

The Comments owned by this Element.
Subsets: Element.ownedElement

ownedElement : Element (0 *); -- source Element
owner : Element (0 1); -- source Element


No additional constraints.


No additional operations.

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