其中出生前的return可自定義，詳情見程式碼：

public static String getBirthDay(long birthTime, long nTime) {

        //是否為出生前
        boolean gestation = false;
        if (birthTime > nTime) {
            gestation = true;
            long temp = birthTime;
            birthTime = nTime;
            nTime = temp;
        }

        //收集生日
        String birth = "";
        //某個日子的年月日
        Date n = new Date(nTime);
        int nDay = n.getDate();
        int nMonth = n.getMonth();
        int nYear = n.getYear();

        //生日的年月日
        Date b = new Date(birthTime);
        int bDay = b.getDate();
        int bMonth = b.getMonth();
        int bYear = b.getYear();

        //生日月的天數，計算是否滿月
        int mothDay = 31;
        if (bMonth == 2) {
            if (isRunYear(bYear)) {
                mothDay = 29;
            } else {
                mothDay = 28;
            }
        } else if (bMonth == 4 || bMonth == 6 || bMonth == 9 || bMonth == 11) {
            mothDay = 30;
        }

        //滿歲：當前年大於出生年，且當前月大於出生月，或當前月等於且出生月當前日大於等於出生日，否則月份為：當前年-出生年-1
        int year = 0;
        if (nYear > bYear) {
            if (nMonth > bMonth || (nMonth == bMonth && nDay >= bDay)) {
                year = nYear - bYear;
            } else {
                year = nYear - bYear - 1;
            }
        }
        if (year > 0) {
            if (!gestation) {
                birth += (year + "歲");
            } else {
                return "寶寶出生" + year + "年前";
            }
        }

        //滿月：當前月大於出生月；且當前日大於等於出生日，否則月份為：當前月-出生月-1
        int month = 0;
        if (nMonth > bMonth) {
            if (nDay >= bDay) {
                month = nMonth - bMonth;
            } else {
                month = nMonth - bMonth - 1;
            }
        }
        if (nYear > bYear && month < 0) {
            month += 12;
        }
        if (month > 0) {
            if (!gestation) {
                birth += (month + "個月");
            } else {
                return "寶寶出生" + month + "個月前";
            }
        }

        int day = 0;
        if (nDay >= bDay) {
            if (nYear > bYear || (nYear == bYear && nMonth >= bMonth)) {
                day += (nDay - bDay);
                if (!gestation) {
                    day += 1;
                }
            }
        } else {
            if (nMonth > bMonth || nYear > bYear) {
                day += (mothDay - bDay + nDay);
                if (!gestation) {
                    day += 1;
                }
            }
        }

        if (day > 0) {
            if (!gestation) {
                birth += (day + "天");
            } else {
                return "寶寶出生" + day + "天前";
            }
        }

        return birth;
    }

    public static boolean isRunYear(int year) {
        return ((year % 4 == 0) && (year % 100 != 0)) || (year % 400 == 0);
    }