Boolean multi = exchange.getIn().getHeader(MongoDbConstants.MULTIUPDATE, Boolean.class);
Boolean upsert = exchange.getIn().getHeader(MongoDbConstants.UPSERT, Boolean.class);
WriteResult result;
WriteConcern wc = extractWriteConcern(exchange);
// In API 2.7, the default upsert and multi values of update(DBObject, DBObject) are false, false, so we unconditionally invoke the
// full-signature method update(DBObject, DBObject, boolean, boolean). However, the default behaviour may change in the future,
// so it's safer to be explicit at this level for full determinism
if (multi == null && upsert == null) {
// for update with no multi nor upsert but with specific WriteConcern there is no update signature without multi and upsert args,