validationPanel = new ValidationPanel();
validationPanel.setInnerComponent(this);
ValidationGroup group = validationPanel.getValidationGroup();
group.add(titleTextField, new ColumnTitleValidator(table));
group.add(intervalStartText, new IntervalBoundValidator());
group.add(intervalEndText, new IntervalBoundValidator(intervalStartText));
validationPanel.addChangeListener(new ChangeListener() {
@Override