Summary

The extension supports composite primary keys declared with @EmbeddedId (HIBERNATE-207). A composite key declared with @IdClass (a non-aggregated identifier) is rejected at boot with FeatureNotSupportedException. Add support for @IdClass as an alternative composite-key declaration.

Notes

@IdClass differs structurally from @EmbeddedId: the identifier is non-aggregated, so its components are top-level entity attributes and PersistentClass.getIdentifierProperty() is null. The clean boot rejection is added by HIBERNATE-207 (replacing the NullPointerException described in HIBERNATE-230).