@SpringBootApplication
@MapperScan("com.hospital.mapper")
@EnableCaching
@EnableScheduling  // 開(kāi)啟定時(shí)任務(wù)
public class SpringBootSystemApplication {
    public static void main(String[] args) {
        SpringApplication.run(SpringBootSystemApplication.class, args);
    }
}

package com.example.task;
import com.baomidou.mybatisplus.core.conditions.update.LambdaUpdateWrapper;
import com.example.entity.Appointment;
import com.example.mapper.AppointmentMapper;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;
import java.time.LocalDate;
import java.time.ZoneId;
import java.util.Date;
@Slf4j
@Component
public class AppointmentTask {
    @Autowired
    private AppointmentMapper appointmentMapper;
    /**
     * 每天凌晨1點(diǎn)執(zhí)行，將已過(guò)期未就診的預(yù)約狀態(tài)改為"已過(guò)期"
     * cron表達(dá)式：秒 分 時(shí) 日 月 星期
     */
    @Scheduled(cron = "0 0 1 * * ?")
    public void cancelExpiredAppointments() {
        log.info("開(kāi)始執(zhí)行過(guò)期預(yù)約取消任務(wù)");
        // 獲取當(dāng)前日期之前的所有預(yù)約（預(yù)約日期小于今天）
        Date today = Date.from(LocalDate.now().atStartOfDay(ZoneId.systemDefault()).toInstant());
        LambdaUpdateWrapper<Appointment> wrapper = new LambdaUpdateWrapper<>();
        wrapper.lt(Appointment::getAppointmentDate, today)
               .eq(Appointment::getStatus, "已預(yù)約")
               .set(Appointment::getStatus, "已過(guò)期");
        int rows = appointmentMapper.update(null, wrapper);
        log.info("過(guò)期預(yù)約取消任務(wù)完成，共更新{}條記錄", rows);
    }
    /**
     * 測(cè)試用：每30秒執(zhí)行一次（取消后注釋）
     */
    // @Scheduled(fixedDelay = 30000)
    // public void testTask() {
    //     log.info("定時(shí)任務(wù)測(cè)試");
    // }
}