Java的list筛选重复的数据然后移除掉

/**
 * 筛选出重复数据然后然移除掉；
 * @author wjk
 * @Date 2021-09-16
 */

private List<AttendEmployeeMonth> getAttendEmployeeMonthRmHaveAttendEmployee(List<AttendEmployeeMonth> attendEmployeeMonthList) {
    //根据列表查询这些员工是否已经做过考勤记录
    List<AttendEmployeeMonth> attendEmployeeMonthListOld = attendEmployeeMonthService.getEmployeeListByAuditBtyArchiveList(attendEmployeeMonthList);
    //若有，则剔除掉该员工，重新组成列表，

    List<AttendEmployeeMonth> attendEmployeeMonthNew = new ArrayList<AttendEmployeeMonth>();

    for(AttendEmployeeMonth attendEmployeeMonth :attendEmployeeMonthList){
            for(AttendEmployeeMonth attendEmployeeMonthOld : attendEmployeeMonthListOld){
                if (attendEmployeeMonth.getBtyArchicesId().equals(attendEmployeeMonthOld.getBtyArchicesId())){
                    attendEmployeeMonthNew.add(attendEmployeeMonth);
            }
        }
    }
    attendEmployeeMonthList.removeAll(attendEmployeeMonthNew);
    //若没有，直接进行之后的操作
    return attendEmployeeMonthList;
}