Java结合Kotlin实现宝宝年龄计算

import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Calendar; public class LifeAge{ /** * @param birthday 日期格式yyyy-MM-dd *                 根据用户生日计算年龄 *                 用Calender对象取得当前日期对象--从对象中分别取出年月日 *                 输出结果 例如 26岁7月零9天 */ public static String getAgeByBirth(String birthday) { //从Calendar对象中或得一个Date对象 Calendar now = Calendar.getInstance(); /*把出生日期放入Calendar类型的bir对象中，进行Calendar和Date类型进行转换*/ Calendar bir = Calendar.getInstance(); SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd"); try { bir.setTime(simpleDateFormat.parse(birthday)); } catch (ParseException e) { e.printStackTrace(); } //如果生日大于当前日期，则抛出异常：出生日期不能大于当前日期 if (now.before(birthday)) { throw new IllegalArgumentException("The birthday is before Now,It's unbelievable"); } //取出当前年月日 int yearNow = now.get(Calendar.YEAR); int monthNow = now.get(Calendar.MONTH) + 1; int dayNow = now.get(Calendar.DAY_OF_MONTH); //取出出生年月日 int yearBirth = bir.get(Calendar.YEAR); int monthBirth = bir.get(Calendar.MONTH) + 1; int dayBirth = bir.get(Calendar.DAY_OF_MONTH); //先day相减,不够向month借,然后month相减,不够向year借,最后year相减。 int day = dayNow - dayBirth; int month = monthNow - monthBirth; //年龄是当前年减去出生年 int year = yearNow - yearBirth; 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。 //借一个月 day = day + now.getActualMaximum(Calendar.DAY_OF_MONTH); } if (month <0) { //一年12个月,借12个月 month = (month + 12) % 12; //借了12个月,少一年 year--; } StringBuilder stringBuilder = new StringBuilder(); stringBuilder.append(year + "岁"); stringBuilder.append(month + "月"); if (day <20) { stringBuilder.append("零" + day + "天"); } else { stringBuilder.append(day + "天"); } if (year == 0 && month == 0 && day == 0) { stringBuilder.delete(0, stringBuilder.length()); stringBuilder.append("今日出生"); } return stringBuilder.toString(); } /*main方法测试*/ public static void main(String[] args) { String birthday = "1993-10-18"; String age = getAgeByBirth(birthday); System.out.print("年龄=" + age); } } 

import java.text.SimpleDateFormat import java.util.* class LifeAge { /** * @param birthday 日期格式yyyy-MM-dd * 根据用户生日计算年龄 * 用Calender对象取得当前日期对象--从对象中分别取出年月日 * 输出结果 例如 26岁9个月零28天 */ fun getAgeByBirth(birthday: String?): String { //从Calendar对象中或得一个Date对象 val now = Calendar.getInstance() /*把出生日期放入Calendar类型的bir对象中，进行Calendar和Date类型进行转换*/ val bir = Calendar.getInstance() val simpleDateFormat = SimpleDateFormat("yyyy-MM-dd") bir.time = simpleDateFormat.parse(birthday) //如果生日大于当前日期，则抛出异常：出生日期不能大于当前日期 require(!now.before(birthday)) { "The birthday is before Now,It's unbelievable" } //取出当前年月日 val yearNow = now[Calendar.YEAR] val monthNow = now[Calendar.MONTH] + 1 val dayNow = now[Calendar.DAY_OF_MONTH] //取出出生年月日 val yearBirth = bir[Calendar.YEAR] val monthBirth = bir[Calendar.MONTH] + 1 val dayBirth = bir[Calendar.DAY_OF_MONTH] //先day相减,不够向month借,然后month相减,不够向year借,最后year相减。 var day = dayNow - dayBirth var month = monthNow - monthBirth //年龄是当前年减去出生年 var year = yearNow - yearBirth 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。 //借一个月 day += now.getActualMaximum(Calendar.DAY_OF_MONTH) } if (month <0) { //一年12个月,借12个月 month = (month + 12) % 12 //借了12个月,少一年 year-- } val stringBuilder = StringBuilder() stringBuilder.append(year.toString() + "岁") stringBuilder.append(month.toString() + "月") if (day <20) { stringBuilder.append("零" + day + "天") } else { stringBuilder.append(day.toString() + "天") } if (year == 0 && month == 0 && day == 0) { stringBuilder.delete(0, stringBuilder.length) stringBuilder.append("今日出生") } return stringBuilder.toString() } } /*main方法测试*/ fun main() { val birthday = "1994-10-18" val age = LifeAge().getAgeByBirth(birthday) print("年龄=$age") }