How do the AbstractTableModel, ColumnModel and TableCellRenderer interact?

Question

could someone please explain to me how the AbstractTableModel, TableColumnModel and the TableCellRenderer interact?
That is, if I have a table which used a custom AbstractTableModel, and a custom TableCellRenderer, then how do I cause the renderer to render the correct data?
Do I have to manually invoke it from my table model? does it get called automatically for every column/row combination?
also if I want to add a column to the table and I use:
TableColumnModel's addColumn(TableColumn colum), do I have to invoke AbstractTableModel's fireTableStructureChanged() as well?
Also, I implemented AbstractTableModel's
Object valueAt(int row, int column)
but that method is never invoked in my code. Is that ok?
int getRowCount(), and int getColumnCount() are invoked on the other hand.
nir

Answer 1

I misspelled the name of the method.
I was using Object getValueAt(int row, int column)...
still this method is never invoked (I have debug messages there and they are never shown).
And I am setting the default renderer...
Here is my ccode:
   // this is how I define my table and table model.
   // PlayerTableDataModel is class implementing AbstractTableModel
   // dataSource is the object that will supply the data that will be presented in the table.
   PlayerTableDataModel tableModel = new PlayerTableDataModel(dataSource);
   table = new JTable(tableModel);
   table.getTableHeader().setReorderingAllowed(false);
   tableModel.setTable(table);
   table.setDefaultRenderer(RoundResult.class, new RoundResultRenderer(dataSource));
   table.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);Here is my PlayerTableDataModel class:
public class PlayerTableDataModel extends AbstractTableModel
    private DataSource dataSource;
    private JTable table;
    public PlayerTableDataModel(DataSource dataSource) {
     super();
     this.dataSource; = dataSource;;     
    // This is the method I invoke when I want to dynamically add a new column to the table.
    public void addNewColumn(GameTableHeaderRenderer headerRenderer) {
     TableColumn newColumn = new TableColumn(getColumnCount());
     newColumn.setHeaderRenderer(headerRenderer);
     newColumn.setResizable(true);
     TableColumnModel cm = table.getColumnModel();
     cm.addColumn(newColumn);
     fireTableStructureChanged();
    public void setTable(JTable table) {
     this.table = table;
    public int getRowCount() {
     return dataSource.getNumRoundsPlayed();
    public int getColumnCount() {
     if (table == null) {
         return 0;
     return dataSource.numberOfPlayers();
    public Object getValueAt(int row, int column) {
     System.out.println("this is never shown");
    public boolean isCellEditable(int row, int col) {
        return false;      
    // I want each cell in the table to hold an object of class RoundResult
    public Class getColumnClass(int c) {
     return RoundResult.class;
}why do I have to implement getValueAt(), if it is never invoked?