java根据生日计算年龄工具类

• 在开发中时常遇到要通过生日计算年龄的需求，这里记录一下

 private static int getAgeByBirth(Date birthday) {
        int age = 0;
        try {
            Calendar now = Calendar.getInstance();
            now.setTime(new Date());// 当前时间

            Calendar birth = Calendar.getInstance();
            birth.setTime(birthday);

            if (birth.after(now)) {//如果传入的时间，在当前时间的后面，返回0岁
                age = 0;
            } else {
                age = now.get(Calendar.YEAR) - birth.get(Calendar.YEAR);
                if (now.get(Calendar.DAY_OF_YEAR) > birth.get(Calendar.DAY_OF_YEAR)) {
                    age += 1;
                }
            }
            return age;
        } catch (Exception e) {//兼容性更强,异常后返回数据
           return 0;
        }
    }

• 调用

 // 定义一个出生时间
        SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Date bithday = format.parse("1994-08-23 17:20:20");
        int age = getAgeByBirth(bithday);
        System.out.println(age);