public void addToQueue(Collection<? extends Var> vars){
  batch.addAll(vars);
  if (batch.size() >= batchSize) {
    submitBatch(batch);
    batch.clear();
  }
}

public void addToQueue ( Collection < ? extends Var > vars ) { batch . addAll ( vars ) ; if ( batch . size ( ) >= batchSize ) { submitBatch ( batch ) ; batch . clear ( ) ; } }
add multiple vars to the queue . these should be inserted in one transaction .
