public static CronPattern of(String pattern) {
		return new CronPattern(pattern);
	}
@Test
	public void patternTest() {
		CronPattern pattern = CronPattern.of("* 0 4 * * ?");
		assertMatch(pattern, "2017-02-09 04:00:00");
		assertMatch(pattern, "2017-02-19 04:00:33");

		// 6位Quartz风格表达式
		pattern = CronPattern.of("* 0 4 * * ?");
		assertMatch(pattern, "2017-02-09 04:00:00");
		assertMatch(pattern, "2017-02-19 04:00:33");
	}