Java 计算年龄

import org.junit.Test;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

/**
 * @author ceshi
 * @Title: JunitAge
 * @ProjectName ceshi
 * @Description: TODO
 * @date 2018/6/2721:00
 */
public class JunitAge {

    SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");

    @Test
    public void testAge()throws Exception{

        int  age = getAge(format.parse("1993-06-27"));
        System.out.println(age);

    }

    //由出生日期获得年龄
    public  int getAge(Date birthDay) throws Exception {
        int age = 0;
        Calendar cal = Calendar.getInstance();
        if (cal.before(birthDay)) {
           return age;
        }
        int yearNow = cal.get(Calendar.YEAR);
        int monthNow = cal.get(Calendar.MONTH);
        int dayNow = cal.get(Calendar.DAY_OF_MONTH);
        cal.setTime(birthDay);

        int yearBirth = cal.get(Calendar.YEAR);
        int monthBirth = cal.get(Calendar.MONTH);
        int dayBirth = cal.get(Calendar.DAY_OF_MONTH);
        //年相减
        age = yearNow - yearBirth;
        //判断月份
        if (monthNow <= monthBirth) {
            if (monthNow == monthBirth) {
                //判断天
                if (dayNow < dayBirth){
                    age--;
                }
            }else{
                age--;
            }
        }
        return age;
    }
}