private SelectionBox<IntItem> createYearSelect() {
        final SelectionBox<IntItem> yearListBox = new SelectionBox<>();
        yearListBox.addValueChangeHandler(e -> {
            int previousYear = getModel().getCurrentMonth().getFullYear();
            int newYear = yearListBox.getValue().getValue();
            int delta = newYear - previousYear;
            addMonths(delta * DateTimeModel.MONTHS_IN_YEAR);
        });
        yearListBox.addDomHandler(e -> {
            if (KeyCodes.KEY_LEFT == e.getNativeKeyCode()) {
                addMonths(-DateTimeModel.MONTHS_IN_YEAR);
            } else if (KeyCodes.KEY_RIGHT == e.getNativeKeyCode()) {
                addMonths(DateTimeModel.MONTHS_IN_YEAR);
            }
        }, KeyDownEvent.getType());

        return yearListBox;
    }
Returns the ListBox for selecting the year
stroom-core-client-widget/src/main/java/stroom/widget/datepicker/client/DefaultMonthSelector.java