Java 根据生日获取年龄（周岁）

约定不等于承诺〃 2022-12-18 15:58 201阅读 0赞

Java 根据生日获取年龄（周岁）。

/**
     * @author zhnagzhixiang on 2020/8/4
    */
    public class SysResourceServiceImpl {
    
        // 根据年月日计算年龄,birthTimeString:"1994-11-14"
        public static int getAgeFromBirthTime(String birthTimeString) {
            // 先截取到字符串中的年、月、日
            int selectYear = Integer.parseInt(birthTimeString.substring(0, 4));
            int selectMonth = Integer.parseInt(birthTimeString.substring(4, 6));
            int selectDay = Integer.parseInt(birthTimeString.substring(6, 8));
            // 得到当前时间的年、月、日
            Calendar cal = Calendar.getInstance();
            int yearNow = cal.get(Calendar.YEAR);
            int monthNow = cal.get(Calendar.MONTH) + 1;
            int dayNow = cal.get(Calendar.DATE);
    
            // 用当前年月日减去生日年月日
            int yearMinus = yearNow - selectYear;
            int monthMinus = monthNow - selectMonth;
            int dayMinus = dayNow - selectDay;
    
            int age = yearMinus;// 先大致赋值
            if (yearMinus < 0) {// 选了未来的年份
                age = 0;
            } else if (yearMinus == 0) {// 同年的，要么为1，要么为0
                if (monthMinus < 0) {// 选了未来的月份
                    age = 0;
                } else if (monthMinus == 0) {// 同月份的
                    if (dayMinus < 0) {// 选了未来的日期
                        age = 0;
                    } else if (dayMinus >= 0) {
                        age = 1;
                    }
                } else if (monthMinus > 0) {
                    age = 1;
                }
            } else if (yearMinus > 0) {
                if (monthMinus < 0) {// 当前月>生日月
                } else if (monthMinus == 0) {// 同月份的，再根据日期计算年龄
                    if (dayMinus < 0) {
                    } else if (dayMinus >= 0) {
                        age = age + 1;
                    }
                } else if (monthMinus > 0) {
                    age = age + 1;
                }
            }
            return age;
        }
    
        public static void main(String[] args) {
            String birthTimeString[] = {
                    "20090929",
                    "20100505",
                    "20100222",
                    "20100510",
                    "20091206",
                    "20091014",
                    "20081123",
                    "20091116",
                    "20100712",
                    "20100531",
                    "20090808",
                    "20091025",
                    "20091018",
                    "20100610",
                    "20091101",
                    "20100120",
                    "20100408",
                    "20090707",
                    "20091212",
                    "20090916",
            };
            for (int i=0;i<birthTimeString.length;i++) {
                System.out.println(getAgeFromBirthTime(birthTimeString[i]) - 1);
            }
        }
    }