JTable - Groupable/Multiline Header

Question

Hi Everybody,
I found this code to create a groupable/multiline header for a JTable. It seems to be working fine with JDK 1.1 and we are using 1.4 now. I keep getting 2 errors with the GroupableTableHeaderUI class and has been busy the whole weekend trying to fix it, with no success. Can someone please help? Thanks. Here is the code:
* |-----------------------------------------------------|
* | | Name | Language |
* | |-----------------|--------------------------|
* | SNo. | | | | Others |
* | | 1 | 2 | Native |-----------------|
* | | | | | 2 | 3 |
* |-----------------------------------------------------|
* | | | | | | |
package tableheader;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.table.*;
import swing.table.*;
public class GroupableHeaderExample extends JFrame {
GroupableHeaderExample() {
super( "Groupable Header Example" );
DefaultTableModel dm = new DefaultTableModel();
dm.setDataVector(new Object[][]{
{"119","foo","bar","ja","ko","zh"},
{"911","bar","foo","en","fr","pt"}},
new Object[]{"SNo.","1","2","Native","2","3"});
JTable table = new JTable( dm ) {
protected JTableHeader createDefaultTableHeader() {
     return new GroupableTableHeader(columnModel);
TableColumnModel cm = table.getColumnModel();
ColumnGroup g_name = new ColumnGroup("Name");
g_name.add(cm.getColumn(1));
g_name.add(cm.getColumn(2));
ColumnGroup g_lang = new ColumnGroup("Language");
g_lang.add(cm.getColumn(3));
ColumnGroup g_other = new ColumnGroup("Others");
g_other.add(cm.getColumn(4));
g_other.add(cm.getColumn(5));
g_lang.add(g_other);
GroupableTableHeader header = (GroupableTableHeader)table.getTableHeader();
header.addColumnGroup(g_name);
header.addColumnGroup(g_lang);
JScrollPane scroll = new JScrollPane( table );
getContentPane().add( scroll );
setSize( 400, 120 );
public static void main(String[] args) {
GroupableHeaderExample frame = new GroupableHeaderExample();
frame.addWindowListener( new WindowAdapter() {
public void windowClosing( WindowEvent e ) {
     System.exit(0);
frame.setVisible(true);
package swing.table;
import java.util.*;
import java.awt.*;
import javax.swing.*;
import javax.swing.table.*;
public class GroupableTableHeader extends JTableHeader {
private static final String uiClassID = "GroupableTableHeaderUI";
protected Vector columnGroups = null;
public GroupableTableHeader(TableColumnModel model) {
super(model);
setUI(new GroupableTableHeaderUI());
setReorderingAllowed(false);
public void setReorderingAllowed(boolean b) {
reorderingAllowed = false;
public void addColumnGroup(ColumnGroup g) {
if (columnGroups == null) {
columnGroups = new Vector();
columnGroups.addElement(g);
public Enumeration getColumnGroups(TableColumn col) {
if (columnGroups == null) return null;
Enumeration enum = columnGroups.elements();
while (enum.hasMoreElements()) {
ColumnGroup cGroup = (ColumnGroup)enum.nextElement();
Vector v_ret = (Vector)cGroup.getColumnGroups(col,new Vector());
if (v_ret != null) {
     return v_ret.elements();
return null;
public void setColumnMargin() {
if (columnGroups == null) return;
int columnMargin = getColumnModel().getColumnMargin();
Enumeration enum = columnGroups.elements();
while (enum.hasMoreElements()) {
ColumnGroup cGroup = (ColumnGroup)enum.nextElement();
cGroup.setColumnMargin(columnMargin);
package swing.table;
import java.util.*;
import java.awt.*;
import javax.swing.*;
import javax.swing.table.*;
import javax.swing.plaf.basic.*;
public class GroupableTableHeaderUI extends BasicTableHeaderUI {
public void paint(Graphics g, JComponent c) {
Rectangle clipBounds = g.getClipBounds();
if (header.getColumnModel() == null) return;
((GroupableTableHeader)header).setColumnMargin();
int column = 0;
Dimension size = header.getSize();
Rectangle cellRect = new Rectangle(0, 0, size.width, size.height);
Hashtable h = new Hashtable();
int columnMargin = header.getColumnModel().getColumnMargin();
Enumeration enumeration = header.getColumnModel().getColumns();
while (enumeration.hasMoreElements()) {
cellRect.height = size.height;
cellRect.y = 0;
TableColumn aColumn = (TableColumn)enumeration.nextElement();
Enumeration cGroups = ((GroupableTableHeader)header).getColumnGroups(aColumn);
if (cGroups != null) {
int groupHeight = 0;
while (cGroups.hasMoreElements()) {
ColumnGroup cGroup = (ColumnGroup)cGroups.nextElement();
Rectangle groupRect = (Rectangle)h.get(cGroup);
if (groupRect == null) {
groupRect = new Rectangle(cellRect);
Dimension d = cGroup.getSize(header.getTable());
groupRect.width = d.width;
groupRect.height = d.height;
h.put(cGroup, groupRect);
paintCell(g, groupRect, cGroup);
groupHeight += groupRect.height;
cellRect.height = size.height - groupHeight;
cellRect.y = groupHeight;
cellRect.width = aColumn.getWidth() + columnMargin;
if (cellRect.intersects(clipBounds)) {
paintCell(g, cellRect, column);
cellRect.x += cellRect.width;
column++;
private void paintCell(Graphics g, Rectangle cellRect, int columnIndex) {
TableColumn aColumn = header.getColumnModel().getColumn(columnIndex);
TableCellRenderer renderer = aColumn.getHeaderRenderer();
Component component = renderer.getTableCellRendererComponent(
header.getTable(), aColumn.getHeaderValue(),false, false, -1, columnIndex);
rendererPane.add(component);
rendererPane.paintComponent(g, component, header, cellRect.x, cellRect.y,
                    cellRect.width, cellRect.height, true);
private void paintCell(Graphics g, Rectangle cellRect,ColumnGroup cGroup) {
TableCellRenderer renderer = cGroup.getHeaderRenderer();
Component component = renderer.getTableCellRendererComponent(
header.getTable(), cGroup.getHeaderValue(),false, false, -1, -1);
rendererPane.add(component);
rendererPane.paintComponent(g, component, header, cellRect.x, cellRect.y,
                    cellRect.width, cellRect.height, true);
private int getHeaderHeight() {
int height = 0;
TableColumnModel columnModel = header.getColumnModel();
for(int column = 0; column < columnModel.getColumnCount(); column++) {
TableColumn aColumn = columnModel.getColumn(column);
TableCellRenderer renderer = aColumn.getHeaderRenderer();
Component comp = renderer.getTableCellRendererComponent(
header.getTable(), aColumn.getHeaderValue(), false, false,-1, column);
int cHeight = comp.getPreferredSize().height;
Enumeration enum = ((GroupableTableHeader)header).getColumnGroups(aColumn);
if (enum != null) {
while (enum.hasMoreElements()) {
ColumnGroup cGroup = (ColumnGroup)enum.nextElement();
cHeight += cGroup.getSize(header.getTable()).height;
height = Math.max(height, cHeight);
return height;
private Dimension createHeaderSize(long width) {
TableColumnModel columnModel = header.getColumnModel();
width += columnModel.getColumnMargin() * columnModel.getColumnCount();
if (width > Integer.MAX_VALUE) {
width = Integer.MAX_VALUE;
return new Dimension((int)width, getHeaderHeight());
public Dimension getPreferredSize(JComponent c) {
long width = 0;
Enumeration enumeration = header.getColumnModel().getColumns();
while (enumeration.hasMoreElements()) {
TableColumn aColumn = (TableColumn)enumeration.nextElement();
width = width + aColumn.getPreferredWidth();
return createHeaderSize(width);
package swing.table;
import java.util.*;
import java.awt.*;
import javax.swing.*;
import javax.swing.table.*;
public class ColumnGroup {
protected TableCellRenderer renderer;
protected Vector v;
protected String text;
protected int margin=0;
public ColumnGroup(String text) {
this(null,text);
public ColumnGroup(TableCellRenderer renderer,String text) {
if (renderer == null) {
this.renderer = new DefaultTableCellRenderer() {
     public Component getTableCellRendererComponent(JTable table, Object value,
boolean isSelected, boolean hasFocus, int row, int column) {
     JTableHeader header = table.getTableHeader();
     if (header != null) {
     setForeground(header.getForeground());
     setBackground(header.getBackground());
     setFont(header.getFont());
setHorizontalAlignment(JLabel.CENTER);
setText((value == null) ? "" : value.toString());
     setBorder(UIManager.getBorder("TableHeader.cellBorder"));
     return this;
} else {
this.renderer = renderer;
this.text = text;
v = new Vector();
* @param obj TableColumn or ColumnGroup
public void add(Object obj) {
if (obj == null) { return; }
v.addElement(obj);
* @param c TableColumn
* @param v ColumnGroups
public Vector getColumnGroups(TableColumn c, Vector g) {
g.addElement(this);
if (v.contains(c)) return g;
Enumeration enum = v.elements();
while (enum.hasMoreElements()) {
Object obj = enum.nextElement();
if (obj instanceof ColumnGroup) {
Vector groups =
(Vector)((ColumnGroup)obj).getColumnGroups(c,(Vector)g.clone());
if (groups != null) return groups;
return null;
public TableCellRenderer getHeaderRenderer() {
return renderer;
public void setHeaderRenderer(TableCellRenderer renderer) {
if (renderer != null) {
this.renderer = renderer;
public Object getHeaderValue() {
return text;
public Dimension getSize(JTable table) {
Component comp = renderer.getTableCellRendererComponent(
table, getHeaderValue(), false, false,-1, -1);
int height = comp.getPreferredSize().height;
int width = 0;
Enumeration enum = v.elements();
while (enum.hasMoreElements()) {
Object obj = enum.nextElement();
if (obj instanceof TableColumn) {
TableColumn aColumn = (TableColumn)obj;
width += aColumn.getWidth();
width += margin;
} else {
width += ((ColumnGroup)obj).getSize(table).width;
return new Dimension(width, height);
public void setColumnMargin(int margin) {
this.margin = margin;
Enumeration enum = v.elements();
while (enum.hasMoreElements()) {
Object obj = enum.nextElement();
if (obj instanceof ColumnGroup) {
((ColumnGroup)obj).setColumnMargin(margin);

Answer 1

in GroupableTableHeaderUI class replace "aColumn.getHeaderRenderer();" by "header.getDefaultRenderer ();" and try again..
this should solve ur problem ..
Indranil