WARNING: The UML2..1.2 Superstructure specification of the UML ComponentRealization metaclass contains some controversial notation direction conventions (as compared with Realization) and some contradictory and duplicated specification text. Therefore a relatively large portion of the UML2.1.2 specification is reproduced here, in order to support this detailed analysis.

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From UML2.1.2:

'The ComponentRealization concept is specialized in the Components package to (optionally) define the Classifiers that realize the contract offered by a component in terms of its provided and required interfaces. ..

Description

In the metamodel, a ComponentRealization is a subtype of Dependencies::Realization ..

Associations:

• abstraction : Component [0..1]
The Component that own this Realization and which is implemented by its realizing classifiers.
{Subsets Element::owner, DirectedRelationship::source, Dependency::client}

• realizingClassifier : Classifier [1]
A classifier that is involved in the implementation of the Component that owns this Realization.
{Subset Dependency::supplier, DirectedRelationship::target}

Semantics
A component’s behavior may typically be realized (or implemented) by a number of Classifiers..

Notation

A component realization is notated in the same way as the realization dependency (i.e., as a general dashed line with an open arrow-head).'

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Please note above that the 'abstraction', which is clearly to be understood as the specification 'which is implemented by its realizing classifiers' is the source (=client), which is exactly the opposite of the convention used in Realization, although it is stated that 'a component realization is notated in the same way as the realization dependency'. We will see in this trail that this is impossible; the specification text is contradictory in a number of places.