How can I subtract two values and compare result in mongodb using Java driver?

Question

Sorry for possible duplicate question... I need remove documents from a collection which have expired time calculated doing System.currentTimeMillis() - doc.lastAccess > doc.ttl . How can I do this using BasicDBObject query (or other most efficient/easy alternative)?

Answer 1

Well. I got the solution... But I read in somewhere that use $where is too slow... Can someone provide me a better approach?

  BasicDBObject q = new BasicDBObject("$where", 
       "new Date().getTime() - this.lastAccess > this.ttl");

  this.collection.remove(q);