@Test
public void testDayGridPositionAtLocationMonthHeaderHitLToR() {

    // This test will not work in a headless configuration.
    if (GraphicsEnvironment.isHeadless()) {
        LOG.fine("cannot run test - headless environment");
        return;
    }
    BasicMonthViewUI ui = getRealizedMonthViewUI(ComponentOrientation.LEFT_TO_RIGHT);
    Point location = getLocationInMonthHeader(ui);
    assertNull("hit in header must return null grid position", 
            ui.getDayGridPositionAtLocation(location.x, location.y));
}