根据日期获取年龄

精确到月

//获取年龄
    public static String getAgeByBirth(String  date) {
        //如果有空格
        int index = date.indexOf(" ");
        if (index != -1){
            date = date.substring(0 , index);
        }
        String[] data = date.split("-");
        Calendar birthday =new GregorianCalendar(Integer.valueOf(data[0]), Integer.valueOf(data[1]), Integer.valueOf(data[2]));
        Calendar now = Calendar.getInstance();
        int day = now.get(Calendar.DAY_OF_MONTH) - birthday.get(Calendar.DAY_OF_MONTH);
        //月份从0开始计算，所以需要+1
        int month = now.get(Calendar.MONTH) +1 - birthday.get(Calendar.MONTH);
        int year = now.get(Calendar.YEAR) - birthday.get(Calendar.YEAR);
        //按照减法原理，先day相减，不够向month借；然后month相减，不够向year借；最后year相减。
        if (day <0) {
            month -=1;
            now.add(Calendar.MONTH, -1);//得到上一个月，用来得到上个月的天数。
            day = day + now.getActualMaximum(Calendar.DAY_OF_MONTH);
        }
        if (month <0) {
            month = (month +12) %12;
            year--;
        }
        StringBuffer tag =new StringBuffer();
        if (year >0) {
            tag.append(year +"岁");
        }
        if (month >0) {
            tag.append(month + "个月");
        }
        if (year ==0 && month ==0 && day ==0) {
            tag.append("今日出生");
        }
        return String.valueOf(tag);
    }

测试数据：

public static void main(String[] args) {
        String date = "1980-01-25";
        String  age = BaseCtrl.getAgeByBirth(date);
        System.out.print(age);
    }

结果：