The addColumn()
method works fine for me:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.table.*;
public class SSCCE extends JPanel
{
SSCCE()
{
DefaultTableModel model = new DefaultTableModel(3, 5);
JTable table = new JTable(model );
JScrollPane scrollPane = new JScrollPane( table );
add(scrollPane);
model.addColumn("abc");
}
private static void createAndShowGUI()
{
JFrame frame = new JFrame("SSCCE");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new SSCCE());
frame.pack();
frame.setLocationByPlatform( true );
frame.setVisible( true );
}
public static void main(String[] args)
{
EventQueue.invokeLater( () -> createAndShowGUI() );
/*
EventQueue.invokeLater(new Runnable()
{
public void run()
{
createAndShowGUI();
}
});
*/
}
}
Post your demo code that demonstrates the problem if you need more help.