UMLNIEM — PSM Representation for XSD Complex Type with Simple Content

The PSM perspective of the current NIEM-UML Profile does not support constraint restrictions for XSD Complex Types with Simple Content.
This capability is needed in extension schemas to help support enterprise/domain/exchange/context specific type constraints.
The attached document provides some explanation of the requirement, the issue, and a proposed profile change

Suggested Resolution:
To enable representation of constraints on Complex Types with simple content (for models other than reference models), the following model construct changes/clarifications are proposed:
• In the PSM perspective, a Class representing Complex Type with Simple Content (CSC) restricting (via <<Restriction>> Realization) another CSC, may define constraining facets via a DataType. In this case, there must be an <<XSDSimpleContent>> Realization whose supplier is the DataType and whose client is the CSC. The <<Restriction>> Realization is implemented in XML Schema through the base attribute on the xsd:restriction element of the CSC (as previously). The constraining facets defined by the DataType are used to populate the content of the xsd:restriction.
• The mapping from PIM to PSM includes a fabricated DataType and <<XSDSimpleContent>> Realization to represent the constraints modeled within the PIM perspective.
Resolution:
The suggested resolution is accepted. Within the PSM perspective, constraining facets on a UML Class representing Complex Type with Simple Content (CSC), which is a restriction of another CSC, shall be represented using the <<XSDSimpleContent>> Realization and a DataType defining the facets.