Representation of an instance in a modeled system, or role played by instances in a certain context.
Under Objecteering, Instances represent both the UML2.0 instance specifications, and the UML2.0 parts within the structured classifiers. The distinction is made through the definition context : if the context is a namespacing context (such as package or class) then it corresponds to the UML2.0 instance specification; if the context of the instance is an instantiation context, such as typically in the case of collaborations, then it corresponds to parts. Parts and ports are treated as instances under Objecteering, whereas UML2.0 will treat them as properties.An Instance is connected to zero or several “Classifier" which declare its structure and behavior. It has a set of attribute values ("Slot" in UML, and “AttributeLink" under Objecteering) and is connected to a set of Links, both sets matching the definitions of its Classifiers/NameSpaces (if there are any). The two sets implement the current state of the Instance.Under Objecteering, an Instance belongs to its NameSpace (Class, Package, Collaboration, etc.), or to another Instance ("Cluster" association).
There exist three important configuration cases for instances under Objecteering :
1 - The “Instance" belongs to a “NameSpace" which is not a Collaboration (e.g. a Package, a Class). This corresponds to the UML2 notion of “InstanceSpecification".
2 - The “Instance" belongs to a Collaboration (It is a “Part", and its links are “Connector “)
3 - The “Instance" belongs to a Collaboration being a Classifier's representation (i.e. its internal structure). In that case, it is a part or a port of the classifier.(UML2.0 semantics): When an instance of the containing classifier is created, a set of instances corresponding to its properties may be created either immediately or at some later time, depending on the multiplicity. These instances are instances of the classifier typing the property. A part specifies that a set of instances may exist; this set of instances is a subset of the total set of instances specified by the classifier typing the part. A part of a classifier declares that an instance of this classifier may contain a set of instances by composition. All such instances are destroyed when the containing classifier instance is destroyed.Under Objecteering, an Instance belongs to another instance (embedded or clustered instances) or belongs to a NameSpace (Package, Class, Collaboration)
UML Mapping
Depending on the context (owner), corresponds to :
An instance,
A part,
A port,
A Link or a Connector
Classes parentes :
Diagrammes de classes : Associations : Attributs :