An InstanceSpecification is a model element that represents an instance of a ‘model artifact’ (or definition). An InstanceSpecification has a value for its properties.
You use the InstanceSpecification to InstanceValue relationship to state that an Instance has a particular InstanceValue.
Relates
The InstanceSpecification to InstanceValue relationship can be drawn like this:
From
To
▪InstanceSpecification
▪InstanceValue
Example
For example, a Window might have a property called Size. An instance of a Window has a value for the attribute Size – for example and area size of medium.
▪You can use an Instance definition to model that a Classifier named Window has an instance called aWindow.
▪You can use an InstanceValue definition to model Medium: Area.
▪You can use the InstanceSpecification to InstanceValue relationship to relate the two.
When you relate the Instance to the InstanceValue through this relationship, the A_instance_instanceValue property of the Instance is filled in appropriately by the value you have connected – and the other way round – if you create the relationship, the relationship line will autodraw on a diagram where the two nodes (Instance and InstanceValue) are placed.
