@Override
public Set<String> getPropertyKeys() {
Set<String> finalproperties = new HashSet<String>();
DBObject element = getDBCollection().findOne(QueryBuilder.start(MONGODB_ID).is(id).get());
Map<String, Object> elementmap = element.toMap();
Iterator<String> propertiesit = elementmap.keySet().iterator();
while (propertiesit.hasNext()) {
String property = propertiesit.next();
if (!property.startsWith("graph:") && (!property.startsWith("_id")) && (!property.equals(StringFactory.LABEL))) {
finalproperties.add(MongoDBUtil.getPropertyName(property));