Java 根据年月日精确计算年龄

 1 import java.text.SimpleDateFormat;
 2 import java.util.Calendar;
 3 import java.util.Date;
 4
 5 /**
 6  * Created by qing on 2017/3/28.
 7  */
 8 public class AgeUtils {
 9     // 根据年月日计算年龄,birthTimeString:"1994-11-14"
10     public static int getAgeFromBirthTime(String birthTimeString) {
11         // 先截取到字符串中的年、月、日
12         String strs[] = birthTimeString.trim().split("-");
13         int selectYear = Integer.parseInt(strs[0]);
14         int selectMonth = Integer.parseInt(strs[1]);
15         int selectDay = Integer.parseInt(strs[2]);
16         // 得到当前时间的年、月、日
17         Calendar cal = Calendar.getInstance();
18         int yearNow = cal.get(Calendar.YEAR);
19         int monthNow = cal.get(Calendar.MONTH) + 1;
20         int dayNow = cal.get(Calendar.DATE);
21
22         // 用当前年月日减去生日年月日
23         int yearMinus = yearNow - selectYear;
24         int monthMinus = monthNow - selectMonth;
25         int dayMinus = dayNow - selectDay;
26
27         int age = yearMinus;// 先大致赋值
28         if (yearMinus < 0) {// 选了未来的年份
29             age = 0;
30         } else if (yearMinus == 0) {// 同年的，要么为1，要么为0
31             if (monthMinus < 0) {// 选了未来的月份
32                 age = 0;
33             } else if (monthMinus == 0) {// 同月份的
34                 if (dayMinus < 0) {// 选了未来的日期
35                     age = 0;
36                 } else if (dayMinus >= 0) {
37                     age = 1;
38                 }
39             } else if (monthMinus > 0) {
40                 age = 1;
41             }
42         } else if (yearMinus > 0) {
43             if (monthMinus < 0) {// 当前月>生日月
44             } else if (monthMinus == 0) {// 同月份的，再根据日期计算年龄
45                 if (dayMinus < 0) {
46                 } else if (dayMinus >= 0) {
47                     age = age + 1;
48                 }
49             } else if (monthMinus > 0) {
50                 age = age + 1;
51             }
52         }
53         return age;
54     }
55
56     // 根据时间戳计算年龄
57     public static int getAgeFromBirthTime(long birthTimeLong) {
58         Date date = new Date(birthTimeLong * 1000l);
59         SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
60         String birthTimeString = format.format(date);
61         return getAgeFromBirthTime(birthTimeString);
62     }
63 }  

精确到月：

 1 // 根据年月日计算年龄,birthTimeString:"1994-11-14"
 2     public static String getAgeFromBirthTime(String birthTimeString) {
 3         // 先截取到字符串中的年、月、日
 4         String strs[] = birthTimeString.trim().split("-");
 5         int selectYear = Integer.parseInt(strs[0]);
 6         int selectMonth = Integer.parseInt(strs[1]);
 7         int selectDay = Integer.parseInt(strs[2]);
 8         // 得到当前时间的年、月、日
 9         Calendar cal = Calendar.getInstance();
10         int yearNow = cal.get(Calendar.YEAR);
11         int monthNow = cal.get(Calendar.MONTH) + 1;
12         int dayNow = cal.get(Calendar.DATE);
13
14         // 用当前年月日减去生日年月日
15         int yearMinus = yearNow - selectYear;
16         int monthMinus = monthNow - selectMonth;
17         int dayMinus = dayNow - selectDay;
18         String  ageToMonth= "1月";
19
20         int age = yearMinus;// 先大致赋值
21         if (yearMinus < 0) {// 选了未来的年份
22             age = 0;
23             ageToMonth = "1月";
24         } else if (monthMinus > 0) {
25             age = 1;
26             ageToMonth = String.valueOf(monthMinus)+"月";
27         } else if (yearMinus > 0) {
28             if (monthMinus < 0) {// 当前月>生日月
29             } else if (monthMinus == 0) {// 同月份的，再根据日期计算年龄
30                 if (dayMinus < 0) {
31                 } else if (dayMinus >= 0) {
32                     age = age + 1;
33                     ageToMonth = String.valueOf(age)+"岁";
34                 }
35             } else if (monthMinus > 0) {
36                 age = age + 1;
37                 ageToMonth = String.valueOf(age)+"岁";
38             }
39         }
40         return ageToMonth;
41     }

1 public static void main(String[] args) {
2         String dataOfBirth = "2017-10-28";
3         String age = getAgeFromBirthTime(dataOfBirth);
4         System.out.println("age:" + age);
5     }