java 计算两个日期相差工作日天数

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.time.DayOfWeek;
import java.time.LocalDate;
import java.time.ZoneId;
import java.util.*;

public class HolidayUtil {

    static List<Date> holiday = new ArrayList<>();

    static List<Date> extraWorkDay = new ArrayList<>();

    public static void init() {
        //TODO 从配置文件或者数据库读入
    }

    /**
     * 计算工作日
     */
    public static int calWorkingDays(Date startTime, Date endTime) {
        int Days = 0;
        //从startTime开始循环，若该日期不是节假日或者不是周六日则天数+1
        Date flag = startTime;//设置循环开始日期
        Calendar cal = Calendar.getInstance();
        //循环遍历每个日期
        while (flag.compareTo(endTime) != 1) {
            cal.setTime(flag);
            Boolean workingDay = isWorkingDay(cal.getTime());
            if (workingDay) {
                //不是节假日或者周末，天数+1
                Days = Days + 1;
            }
            //日期往后加一天
            cal.add(Calendar.DAY_OF_MONTH, +1);
            flag = cal.getTime();
        }
        return Days;
    }

    public static LocalDate DateToLocalDate(Date date) {
        return date.toInstant().atZone(ZoneId.systemDefault()).toLocalDate();
    }

    public static Boolean isWorkingDay(Date date) {
        //是否加班日
        if (extraWorkDay.contains(date)) {
            return true;
        }
        //是否节假日
        if (holiday.contains(date)) {
            return false;
        }
        LocalDate dateTime = HolidayUtil.DateToLocalDate(date);
        //如果是1-5表示周一到周五  是工作日
        DayOfWeek week = dateTime.getDayOfWeek();
        if (week == DayOfWeek.SATURDAY || week == DayOfWeek.SUNDAY) {
            return false;
        }
        return true;
    }

    public static void main(String[] args) throws ParseException {
        init();
        String dateStr1 = "2022-05-27";
        String dateStr2 = "2022-06-01";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        Date date1 = sdf.parse(dateStr1);
        Date date2 = sdf.parse(dateStr2);
        System.out.println("工作日:" + calWorkingDays(date1, date2));
    }
}