Ciao sto tentando di popolare un array di JLabel e uno di TextField
ma quando nel metodo addLabel aggiungo la label l'array mi va in nullpointer???


codice:
class JTableButtonMouseListener implements MouseListener {
     
  private JLabel[] lblVet;
  private  JTextField[] txtVet;
   private JTableButton frameOwner;

   
   public JTableButtonMouseListener(JTable table,JTableButton frameOwner) {
  tableListener = table;
  this.frameOwner = frameOwner;
       
   }
 public void clickOpenDialog(MouseEvent e) {
   MouseEvent buttonEvent;
    int nCol = frameOwner.getTable().getColumnCount()-1;
     JPanel pan = new JPanel();
    lblVet = new JLabel[nCol];
    txtVet = new JTextField[nCol];
    System.out.println(nCol);
  //aggiungere bottoni
     for(int k=0;k<nCol;k++)   
   {   
       this.addLabel(k);
      pan.add(lblVet[k]);
       this.addTextField(k);
      pan.add(txtVet[k]);
   
   }
   for(int k=0;k<nCol;k++)   
   {
     lblVet[k].setText(frameOwner.getTable().getColumnName(k));
     txtVet[k].setText(frameOwner.getTable().getValueAt(frameOwner.getTable().getSelectedRow(),k).toString());
     
   }

   
   frm = new JFrame();
   
   btn_Salva.setText("SALVA");
   btn_Salva.addActionListener(new ActionListener()
     {
       public void actionPerformed(ActionEvent e)
       {
        btn_Salva_actionPerformed(e);
       }
     });
    GridLayout layout = new GridLayout(3,2);
   btn_Salva.setSize(100,20);
   pan.add(btn_Salva);
   pan.setLayout(layout);
   frm.getContentPane().add(pan);
   frm.pack();
   frm.setVisible(true);
 } 

 private void addLabel(int k)
 {
   JLabel lbl = new JLabel();
    lbl.setSize(50,50);
    lblVet[k].add(lbl);
 }
 private void addTextField(int k)
 {
   JTextField txt = new JTextField();
   txt.setSize(50,50);
   txtVet[k].add(txt);
 }