public static int age(Date birthday, Date dateToCompare) {
		Assert.notNull(birthday, "Birthday can not be null !");
		if (null == dateToCompare) {
			dateToCompare = date();
		}
		return age(birthday.getTime(), dateToCompare.getTime());
	}
@Test
	public void ageTest() {
		final String d1 = "2000-02-29";
		final String d2 = "2018-02-28";
		final int age = DateUtil.age(DateUtil.parseDate(d1), DateUtil.parseDate(d2));

		// issue#I6E6ZG，法定生日当天不算年龄，从第二天开始计算
		assertEquals(17, age);
	}