[Swing] How to expose processFocusEvent when JFormattedTextField is already

Hi,
I want to override it since there is a bug, as I was told, that the JFormattedTextField, when it is set to COMMIT_OR_REVERT, it can't accept a blank value, it would return the previous value which it is not desired. But I can't set it to COMMIT because I'd like to revert the values if the user enters the wrong value.
Could you please provide an example of FocusListener that does the same thing as this?

final JFormattedTextField field = new JFormattedTextField(NumberFormat.getInstance()) {  
    @Override  
    protected void processFocusEvent(final FocusEvent e) {  
        if (e.isTemporary()) {  
            return;  
        }  
  
        if (e.getID() == FocusEvent.FOCUS_LOST) {  
            if (getText() == null || getText().isEmpty()) {  
                setValue(null);  
            }  
        }  
        super.processFocusEvent(e);  
    }  
}; 

Thanks
Jack