code: public int ENgetnodeindex( String id ) throws EpanetException {
          int[] index = new int[1];
          int error = epanet.ENgetnodeindex(id, index);
          checkError(error);
          return index[0];
      }
docs: Retrieves the index of a node with a specified ID.
  
  @param id the node id.
  @return the node index.
  @throws EpanetException