YYYY-MM-DDThh：mm：ss在Java中老化的字符串

Question

我有一个格式为YYYY-MM-DDThh：mm：ss的字符串，该字符串是从xml文件中提取的。

此字符串代表出生日期。

如何使用Java查找人的年龄（整数）？

Answer 1

给定特定的日期格式，可以如下计算年龄：

public class AgeCalculator {

public static int calculateAge(Date birthdate) {
    Calendar birth = Calendar.getInstance();
    birth.setTime(birthdate);
    Calendar today = Calendar.getInstance();

    int yearDifference = today.get(Calendar.YEAR) - birth.get(Calendar.YEAR);

    if (today.get(Calendar.MONTH) < birth.get(Calendar.MONTH)) {
        yearDifference--;
    } else {
        if (today.get(Calendar.MONTH) == birth.get(Calendar.MONTH)
                && today.get(Calendar.DAY_OF_MONTH) < birth.get(Calendar.DAY_OF_MONTH)) {
            yearDifference--;
        }
    }
    return yearDifference;
}

public static void main(String[] args) throws ParseException {
    // date format yyyy-MM-dd'T'HH:mm:ss
    String birthdateStr = "2013-07-09T12:17:58-04:00";
    SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
    Date birthdate = df.parse(birthdateStr);
    System.out.println(AgeCalculator.calculateAge(birthdate));
}
}