public EntityPropertyReference withExternalIdProperty(java.util.Map<String, String> externalIdProperty) {
        setExternalIdProperty(externalIdProperty);
        return this;
    }
<p>
A mapping of external IDs to property names. External IDs uniquely identify properties from external data stores.
</p>

@param externalIdProperty
       A mapping of external IDs to property names. External IDs uniquely identify properties from external data
       stores.
@return Returns a reference to this object so that method calls can be chained together.
aws-java-sdk-iottwinmaker/src/main/java/com/amazonaws/services/iottwinmaker/model/EntityPropertyReference.java