Tab on editable JComboBox inside JTable transfers focus outside JTable

This bug was originally submitted as the first part of 4528436 and was closed as a duplicate of RFE 4307147. The submitter and I both believe that this issue is unrelated to that RFE. I am therefore opening this new bug. The original description for that issue is:

A: regarding termination of edit

1. when tabbing out of an editing combo (caret blinking in
its JTextField, does accept key input) focus is transferred to
the next component _outside_ the table. In the example that's the
button if the scrollbar is not visible, it's the ScrollBar if visible
(IMO that's another bug: scrollbars should _never_ be focusOwners).

2. same happens when hitting enter

Code:

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

import java.awt.event.*;
import java.awt.*;
import java.beans.*;
//import de.kleopatra.support.debugon.*;

/**
 * Trace focus with editable combo as editor
 */
public class ClickCombo {

protected JFrame frame ;
// table vars
protected final int ROWS = 15;
protected final int COLUMNS = 3;
protected DefaultTableModel model;
protected JTable table;


public ClickCombo() {
frame = new JFrame("ClickCombo");
frame.setDefaultCloseOperation(frame.EXIT_ON_CLOSE);
frame.getContentPane().add(buildMainPanel());
frame.getContentPane().add(buildButtonPanel(),
BorderLayout.SOUTH);
frame.pack();
// frame.setSize(300, 200);
frame.show();
installFocusTracer();
}

//---------------------------tracing focus

  protected void installFocusTracer() {
   KeyboardFocusManager focusManager = KeyboardFocusManager.
   getCurrentKeyboardFocusManager();
   new FocusOwnerTracer(focusManager);
  }
  
  public class FocusOwnerTracer implements PropertyChangeListener {
public static final String FOCUS_OWNER_PROPERTY = "focusOwner";
protected KeyboardFocusManager focusManager;

public FocusOwnerTracer(KeyboardFocusManager focusManager) {
this.focusManager = focusManager;
startListening();
}

public void startListening() {
if (focusManager != null) {

focusManager.addPropertyChangeListener(FOCUS_OWNER_PROPERTY, this);
}
}

public void stopListening() {
if (focusManager != null) {

focusManager.removePropertyChangeListener(FOCUS_OWNER_PROPERTY, this);
}
}

public void propertyChange(PropertyChangeEvent e) {
Component oldOwner = (Component) e.getOldValue();
Component newOwner = (Component) e.getNewValue();
ebug("focusOwner changed: ", "");
debugClass(" old: ", oldOwner);
debugClass(" new: ", newOwner);
}

protected void debugClass(String msg, Object o) {
ebug(msg, o != null ? o.getClass() : null);
}
}

//---------------------------helper

protected void ebug(String text, Object o) {
System.out.println(text + o);
}

//---------------------------init ui

protected JComponent buildMainPanel() {
JPanel panel = new JPanel();
panel.setLayout(new BorderLayout());
initTable();
JScrollPane scroll = new JScrollPane(table);
panel.add(scroll);
return panel;
}

protected void initTable() {
table = createTable(ROWS, COLUMNS);
model = (DefaultTableModel) table.getModel();
table.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
initComboEditor(0, true);
}

protected void initComboEditor(int col, boolean editable) {
String[] list = { "one", "two", "three", "four", "five", "six"
};
JComboBox box = new JComboBox(list);
// trying to properly get key input if table surrenders focus
/* {
public void requestFocus() {
ebug("Combo: request focus ","");
if (isEditable()) {

getEditor().getEditorComponent().requestFocus();
} else {
super.requestFocus();
}
}
};
*/
box.setEditable(editable);
// setBoxVerifier((box));
TableCellEditor editor = new DefaultCellEditor(box);
setColumnEditorAt(editor, col);
}

protected void setColumnEditorAt(TableCellEditor editor, int col) {
table.getColumnModel().getColumn(col).setCellEditor(editor);
}

protected JComponent buildButtonPanel() {
JPanel panel = new JPanel();
final JButton button = new JButton("surrender off");
button.setMnemonic('s');
frame.getRootPane().setDefaultButton(button);
ActionListener action = new ActionListener() {
public void actionPerformed(ActionEvent event) {
boolean surrender =
!table.getSurrendersFocusOnKeystroke();
table.setSurrendersFocusOnKeystroke(surrender);
if (surrender) {
button.setText("surrender on");
} else {
button.setText("surrender off");
}
}
};
button.addActionListener(action);
panel.add(button);
return panel;
}

//---------------------------factory methods

protected JTable createTable(int r, int c) {
JTable table= new JTable(r, c);
return table;
}

//---------------------------Main

public static void main(String[] args) {
// LFSwitcher.windowsLF();
new ClickCombo();
}
}