JTable displays only default column headers

Question

Hello,
after a tblModel.setDataVector(dataArray, (Object[])headers) I check the header with a System.out.println(tblModel.getColumnName(0)) and it's correct. But only the capitals A, B, C ... are displayed as headers. I am using a DefaultTableModel. Any associations?
Regards
Joerg

Answer 1

Some code will better demonstrate the problem.
Without a TableColumnModel in the constructor and with table.setAutoCreateColumnsFromModel(true); (default) the headers are painted, but then the CellRenderer won't work.
With a TableColumnModel and table.setAutoCreateColumnsFromModel(false) it's better.
It seems that if you want to use a renderer you have to supply a TableColumnModel as well.
As the TableColumnModel is in fact of no interest to me in this case, I only coded what I thought to be the minimum necessary. But now it has become so little that the headers are not dispayed at all. What is missing?
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.table.*;
public class TTest extends JFrame
{ JTable table = null;
  public TTest()
  { setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setSize(300, 300);
    Container cp = getContentPane();
    int countOfColumns=3;
    String[] headers = {"One","Two","Three"};
    Object[][] dataArray= {{"R1-C1","R1-C2","R1-C3"},
           {"R2-C1","R2-C2","R2-C3"},
           {"R3-C1","R3-C2","R3-C3"}};
    DefaultTableModel tblModel = new DefaultTableModel(20, countOfColumns)
    { // Make read-only
      public boolean isCellEditable(int x, int y)
      { return false;
    createTable(tblModel, 2);
    JScrollPane scrollPane = new JScrollPane(table);
    cp.add(scrollPane, BorderLayout.CENTER);
    System.out.println(tblModel.getColumnName(0));
    tblModel.setDataVector(dataArray, (Object[])headers);
    System.out.println(tblModel.getColumnName(0));
    setVisible(true);
  public void createTable(DefaultTableModel tblModel, int twoColumn)
    DefaultTableColumnModel tblColModel= new DefaultTableColumnModel();
    for (int i=0; i<tblModel.getColumnCount(); i++)
    { tblColModel.addColumn(new TableColumn(i));
    table= new JTable(tblModel, tblColModel);
//    table= new JTable(tblModel);
//  Without the following line the renderer won't work; but now the table headers
//  are no more created automatically.
    table.setAutoCreateColumnsFromModel(false);
    table.getColumnModel().getColumn(twoColumn-1).setCellRenderer
                              (new RightJustCellRenderer());
  class RightJustCellRenderer extends DefaultTableCellRenderer
  { public RightJustCellRenderer()
    { setHorizontalAlignment(SwingConstants.RIGHT);
  public static void main(String args[])
  { new TTest();
}