NullPointerException on list.add

Question

I am getting a NullPointerException at the modelData.add(i, es) method. I know from debugging that es isn't null. I'm really confused, thanks.

public class EventTableModel extends AbstractTableModel {      //private int rowCount = 0;     protected List<EventSeat> modelData;     private static final int COLUMN_COUNT = 3;     private Event e;     Event j = GUIpos.m;     int i = 1;  public EventTableModel(Event e) {     this.e = e;     try {         System.out.println(modelData);         for (EventSeat es : e.getEventSeats()) {             modelData.add(i, es);             i++;         }     } catch (DataException ex) {         Logger.getLogger(EventTableModel.class.getName()).log(Level.SEVERE, null, ex);     }  } 

Answer 1

You need to initialize a List to not get the NullPointerException.

protected List<EventSeat> modelData = new ArrayList<EventSeat>();