String description = metadataInterner.intern(metadata.getStringAttribute(DESCRIPTION_META_DATA_ATTRIBUTE, ""));
RevisionType type = RevisionType.valueOf(metadata.getStringAttribute(REVISION_TYPE_META_DATA_ATTRIBUTE, RevisionType.EDIT.name()));
final UserId userId = UserId.getUserId(userName);
final List<OWLOntologyChangeRecord> changeRecords = internChangeRecords(list, axiomInterner, ontologyIDInterner);
Revision revision = new Revision(userId, revisionNumber, changeRecords, list.getTimestamp(), description, type);
addRevision(revision);
}