用正则表达式匹配,从1970-01-01开始往后2万天逐一测试日期有效性,包括闰年2月29日,都可以校验通过。

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class TempTest {
	public static void main(String[] args) throws Exception {
		Date date = new Date(0);
		DateFormat df = new SimpleDateFormat("yyyy-MM-dd");
		Calendar cale = Calendar.getInstance();
		cale.setTime(date);
		for (int i = 0; i < 20000; i++) {
			if (!isValidDate(df.format(date))) {
				System.out.println("校验失败:" + df.format(date));
			}
			cale.add(Calendar.DAY_OF_YEAR, 1);
		}
		System.out.println(df.format(cale.getTime()) + " End.");
	}

	/**
	 * 判断日期格式:yyyy-mm-dd
	 * 
	 * @param sDate
	 * @return
	 */
	public static boolean isValidDate(String sDate) {
		String datePattern1 = "\\d{4}-\\d{2}-\\d{2}";
		String datePattern2 = "^((\\d{2}(([02468][048])|([13579][26]))"
				+ "[\\-\\/\\s]?((((0?[13578])|(1[02]))[\\-\\/\\s]?((0?[1-9])|([1-2][0-9])|"
				+ "(3[01])))|(((0?[469])|(11))[\\-\\/\\s]?((0?[1-9])|([1-2][0-9])|(30)))|(0?2[\\-\\/\\s]?"
				+ "((0?[1-9])|([1-2][0-9])))))|(\\d{2}(([02468][1235679])|([13579][01345789]))[\\-\\/\\s]?("
				+ "(((0?[13578])|(1[02]))[\\-\\/\\s]?((0?[1-9])|([1-2][0-9])|(3[01])))|(((0?[469])|(11))[\\-\\/\\s]?"
				+ "((0?[1-9])|([1-2][0-9])|(30)))|(0?2[\\-\\/\\s]?((0?[1-9])|(1[0-9])|(2[0-8]))))))";
		if ((sDate != null)) {
			Pattern pattern = Pattern.compile(datePattern1);
			Matcher match = pattern.matcher(sDate);
			if (match.matches()) {
				pattern = Pattern.compile(datePattern2);
				match = pattern.matcher(sDate);
				return match.matches();
			} else {
				return false;
			}
		}
		return false;
	}

}