一、SpringTask概念

        Spring Task是spring框架提供的任务调度工具，可以按照约定的时间自动执行某个代码逻辑

作用就是定时执行某段java代码。

二、cron表达式

三、maven坐标依赖

        spring Task的maven坐标为spring-context，因为spring-boot-starter中包含了spring-context坐标，根据依赖的传递性，所以这里只需引入springboot starter的依赖即可。

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter</artifactId>
</dependency>

第四步：在启动类添加@EnableScheduling注解

package com.sky;

import lombok.extern.slf4j.Slf4j;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.transaction.annotation.EnableTransactionManagement;

@SpringBootApplication
@Slf4j
@EnableScheduling//开启定时任务功能
public class SkyApplication {
    public static void main(String[] args) {
        SpringApplication.run(SkyApplication.class, args);
        log.info("server started");
    }
}

第五步：实现超时订单和派送订单

package com.sky.task;

import com.sky.entity.Orders;
import com.sky.mapper.OrderMapper;
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.LocalDateTime;
import java.util.List;

@Component
@Slf4j
public class OrderTask {

    @Autowired
    private  OrderMapper orderMapper;

    /**
     * 处理订单超时方法
     */
    @Scheduled(cron="0 * * * * ?")
    //@Scheduled(cron = "1/5 * * * * ?")
    public void processTimeoutOrder(){
        log.info("处理超时订单:{}", LocalDateTime.now());
        //查询15分钟之前未支付订单
        LocalDateTime time=LocalDateTime.now().plusMinutes(-15);
        List<Orders> ordersList=orderMapper.getByStatusAndOrderTimeLT(time,Orders.PENDING_PAYMENT);
        if(ordersList!=null&&ordersList.size()>0){
            //遍历超时的订单，并将状态设置成取消
            for(Orders order:ordersList){
                order.setStatus(Orders.CANCELLED);
                order.setCancelReason("订单超时，自动取消");
                order.setCancelTime(LocalDateTime.now());
                orderMapper.update(order);
            }
        }
    }
    /**
     * 处理一直处于派送中的订单状态
     */
    @Scheduled(cron="0 0 1 * * ?")
    //@Scheduled(cron = "0/5 * * * * ?")
    public void processDeliveryOrder(){//每天凌晨一点触发一次
        log.info("处理派送中的订单:{}",LocalDateTime.now());
        //查询15分钟之前未支付订单
        LocalDateTime time=LocalDateTime.now().plusMinutes(-60);
        List<Orders> ordersList=orderMapper.getByStatusAndOrderTimeLT(time,Orders.DELIVERY_IN_PROGRESS);
        if(ordersList!=null&&ordersList.size()>0){
            //遍历超时的订单，并将状态设置成取消
            for(Orders order:ordersList){
                order.setStatus(Orders.COMPLETED);
                order.setDeliveryTime(LocalDateTime.now());
                orderMapper.update(order);
            }
        }
    }
}