public void testToCalendar_Null() throws Exception {
        assertThat(toCalendar(null), is(nullValue()));
    }

    /**
     * @throws Exception
     */
    @Test
    public void testToCalendar_EmptyString() throws Exception {
        assertThat(toCalendar(""), is(nullValue()));
    }

    /**
     * @throws Exception
     */
    @Test
    public void testToCalendar_ShortStyle() throws Exception {