Substituir lista da JComboBox

import java.awt.*;
import javax.swing.*;

public class TablePopupComboFrame extends JFrame {
JPanel jPanel1 = new JPanel();
JComboBox combo = new JComboBox();

public TablePopupComboFrame() {
try {
jbInit();
}
catch(Exception e) {
e.printStackTrace();
}
combo.addItem("one");
combo.addItem("two");
combo.addItem("three");
combo.addItem("four");

combo.setUI(new MyComboUI());
}

public static void main(String[] args) {
TablePopupComboFrame f = new TablePopupComboFrame();
f.pack();
f.setLocation(300,300);
f.show();
}
private void jbInit() throws Exception {
this.getContentPane().add(jPanel1, BorderLayout.CENTER);
jPanel1.add(combo, null);
}
}

import javax.swing.*;
import javax.swing.plaf.basic.*;

public class MyComboUI extends BasicComboBoxUI {

protected ComboPopup createPopup() {

return new TableComboPopup(comboBox, this);
}
public JList getList()
{
return listBox;
}
}

import java.awt.*;
import java.awt.event.*;

import javax.swing.*;
import javax.swing.event.*;
import javax.swing.plaf.basic.*;
import javax.swing.table.*;

public class TableComboPopup extends BasicComboPopup implements ListSelectionListener, ItemListener
{

private JList list = new JList();
private JComboBox combo;
private MyComboUI ui;
private PopupTableModel tm ;
private final JTable table;
private JScrollPane pane;

public TableComboPopup(JComboBox combo, MyComboUI ui)
{
super(combo);
this.combo = combo;
this.ui = ui;
tm = new PopupTableModel();
table = new JTable(tm);
pane = new JScrollPane(table);
table.getSelectionModel().setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
table.getSelectionModel().addListSelectionListener(this);
combo.addItemListener(this);
}

public void show()
{
System.out.println("show called ");
super.removeAll();
tm.fireTableStructureChanged();
Dimension dim = new Dimension(combo.getPreferredSize().width,ui.getList().getPreferredScrollableViewportSize().height);
pane.setPreferredSize(dim);
super.add(pane);
selectRow();
super.show();
}
private void selectRow()
{
int index = combo.getSelectedIndex();
System.out.println("selecting row in table: "+index);
if (index == -1) return;
table.setRowSelectionInterval(index,index);
}

public void valueChanged(ListSelectionEvent e) {
combo.setSelectedIndex(table.getSelectedRow());
}
public void itemStateChanged(ItemEvent e) {
if (e.getStateChange() == e.DESELECTED) return;
table.getSelectionModel().removeListSelectionListener(this);
selectRow();
table.getSelectionModel().addListSelectionListener(this);
}

private class PopupTableModel extends AbstractTableModel
{
public int getColumnCount()
{
return 1;
}
public int getRowCount()
{
return combo.getItemCount();
}
public String getColumnName(int columnIndex)
{
return "Items";
}
public boolean isCellEditable(int row, int col)
{
return false;
}
public Object getValueAt(int r,int c)
{
return combo.getItemAt(r);
}
}
}

-----------------------------
| Item 01                   |+|
-----------------------------
|Código  |Nome             |
-----------------------------
|Item 01 |Item 01          |
|Item 02 |Item 02          |
-----------------------------

-------------------  
 | 13             |+|  
 -----------------------  
 |Codigo | Nome      |
 |---------------------- 
 |13512  | Fulano       
 |13456  | Beltrano    
 |13748  | Ciclano      
 |13748  | Berenice    
 |13435  | Bartolomeu
 |13978  | Zoroastro  
 |13800  | Zulmira     
 |13965  | Joaquina    
 |13798  | Clodomiro  
 ------------------------