code: public WriteResult insert(final DBObject document, final WriteConcern writeConcern) {
          return insert(asList(document), writeConcern);
      }
docs: Insert a document into a collection. If the collection does not exists on the server, then it will be created. If the new document
  does not contain an '_id' field, it will be added.
  
  @param document     {@code DBObject} to be inserted
  @param writeConcern {@code WriteConcern} to be used during operation
  @return the result of the operation
  @throws com.mongodb.DuplicateKeyException if the write failed to a duplicate unique key
  @throws com.mongodb.WriteConcernException if the write failed due some other failure specific to the insert command
  @throws MongoException if the operation failed for some other reason
  @mongodb.driver.manual tutorial/insert-documents/ Insert Documents