public static DateTime parse(CharSequence dateStr, DateFormat dateFormat) {
		return new DateTime(dateStr, dateFormat);
	}
@Test
	public void parseTest4() {
		final String ymd = DateUtil.parse("2019-3-21 12:20:15", "yyyy-MM-dd").toString(DatePattern.PURE_DATE_PATTERN);
		assertEquals("20190321", ymd);
	}