DefaultCellEditor in JTable can not update itself when the value changes

Question

Hi,
I have a JTable which has 4 columns. The 3rd column has a comboBox. whenever I select an item from the first row, the cell at (currentrow, 4thcolumn) will be updated according to the item selected.
Now the problem is, after selecting the item in any cell with 3rd column, the row is updated correctly, but then all comboBox in column 3 are gone! I cannot figure out what causes this. Please help! Any suggestion will be greatly appreciated!
Jing

Answer 1

Thanks! Could you give more details on how to use the second approach?
I have a table with two columns, one called ID and the other called Value. I'm using JComboBox for the Value column. Whenever I select an item from the comboBox, I want the value in the cell under the ID column to change value to the value selected in the comboBox.
The problem I'm having now is although I can change the value in the comboBox and which triggers the event to change the value under the ID column, when I click the comboBox of another row, the cell under ID of the previous row changed also, before the value under ID of the current selected row.
I think the problem is there is no distinct comboBox for each row of the table. Seems like when one box change and trigger an event, that event performed in every other rows in the table.
Following is the code:
public class Test extends JPanel{
     DefaultTableModel tm;
     JTable table;
     JScrollPane nscrollPane;
     public int total=4;
     public Vector datavec, thvec;
     public Test(Vector datavec, Vector thvec){
          this.datavec=datavec;
          this.thvec=thvec;
     tm = new DefaultTableModel(datavec,thvec);
          table = new JTable(tm);
          table.addMouseListener(new PopupListener(table));
// table.addMouseListener(new PopupListener(table));
//tm.setTableHeader(table.getTableHeader()); //ADDED THIS
int height = table.getRowHeight()*table.getRowCount();
table.setPreferredScrollableViewportSize(new Dimension(500, height));
//Create the scroll pane and add the table to it.
nscrollPane = new JScrollPane(table);
setUpNNColumn(table, table.getColumnModel().getColumn(1));
//Add the scroll pane to this panel.
add(nscrollPane);
public void updateLabel(Integer size)
     int r=table.getSelectedRow();
     if(r!=-1)
     ((Vector)datavec.elementAt(r)).setElementAt(size, 0);
     repaint();
public void setUpNNColumn(JTable table, TableColumn nnColumn) {
          //Set up the editor for the sport cells
          JComboBox comboBox = new JComboBox();
          comboBox.addActionListener(new ComboBoxListener());
          int num=total/2;
          for(int i=0; i<2; i++){
               comboBox.addItem(new Integer(num*(i+1)));
          comboBox.setSelectedIndex(1);
          nnColumn.setCellEditor(new DefaultCellEditor(comboBox));
private class ComboBoxListener implements ActionListener{
     public void actionPerformed(ActionEvent e)
          JComboBox cb = (JComboBox)e.getSource();
Integer size = (Integer)cb.getSelectedItem();
     updateLabel(size);
private static void createAndShowGUI(Vector a, Vector b) {
\ JFrame.setDefaultLookAndFeelDecorated(true);
//Create and set up the window.
JFrame frame = new JFrame("Nearest Neighbor Fact Table");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Create and set up the content pane.
Test newContentPane = new Test(a, b);
newContentPane.setOpaque(true); //content panes must be opaque
frame.setContentPane(newContentPane);
//Display the window.
frame.pack();
frame.setVisible(true);
public static void main(String[] args) {
     int patidx, hitnum=2;
     Vector a=new Vector();
     Vector a1=new Vector();
     Vector a2=new Vector();
     a1.add(new Integer(1));
     a1.add(new Integer(4));
     a.add(a1);
     a2.add(new Integer(2));
     a2.add(new Integer(4));
     a.add(a2);
     Vector b=new Vector();
     b.add("ID");
     b.add("Value");
     //StatTableGUI.createAndShowGUI(gd);
     Test.createAndShowGUI(a,b);
Any suggestions? Thanks!
Jing