{
RelationalClassMapping classMapping = (RelationalClassMapping)mapping;
if (classMapping.isInner())
{
IndexColumn indexColumn = classMapping.getSourceKey().findIndexColumn(column);
if (indexColumn != null)
{
Object value = instance.findValue(attribute.getName(), Undefined.VALUE);
if (value == null)
{
return null;
}
if (value instanceof OIDHolder)
{
OID oid = ((OIDHolder)value).getOID();
if (oid != null && indexColumn.getOrdinal() < oid.getCount())
{
return oid.getValue(indexColumn.getOrdinal());
}
}
}
}
}