java 日期格式验证

private static void test(String stringdate) {
		System.out
				.println("输入[" + stringdate + "]是否合法:" + validate(stringdate));
	} 	

	
	
	/** 判断主方法 */
	public static boolean validate(String dateString) {
		//使用正则表达式 测试 字符 符合 dddd-dd-dd 的格式(d表示数字)	
		Pattern p = Pattern.compile("\\d{4}\\d{1,2}\\d{1,2}+");		
		Matcher m = p.matcher(dateString);
		if (!m.matches()) {
			return false;
		} //得到年月日		
		String[] array = dateString.split("-");
		int year = Integer.valueOf(array[0]);

		int month = Integer.valueOf(array[1]);
		int day = Integer.valueOf(array[2]);
		if (month < 1 || month > 12) {
			return false;
		}
		int[] monthLengths = new int[] { 0, 31, -1, 31, 30, 31, 30, 31, 31, 30,
				31, 30, 31 };
		if (isLeapYear(year)) {
			monthLengths[2] = 29;
		} else {
			monthLengths[2] = 28;
		}
		int monthLength = monthLengths[month];
		if (day < 1 || day > monthLength) {
			return false;
		}
		return true;
	}

	/** 是否是闰年 */
	private static boolean isLeapYear(int year) {
		return ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0);
	}