code: public void enqueueAll(
        final Collection<Pair<ExecutionReference, ExecutableFlow>> collection)
        throws ExecutorManagerException {
      for (final Pair<ExecutionReference, ExecutableFlow> pair : collection) {
        enqueue(pair.getSecond(), pair.getFirst());
      }
    }
docs: <pre>
  Enqueues all the elements of a collection
  
  @param collection
  
  @throws ExecutorManagerException
  case 1: if blocking queue put method fails due to
  InterruptedException
  case 2: if there already an element with
  same execution Id
  </pre>