本文主要是介绍乐观锁解决库存超卖问题，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！
public BaseResult creatOneOrder(FlightOrderServiceImpl orderService, List<Map<String, String>> passengers,Map<String, String> selectFlightMap,String account) throws Exception {//如果是单程//判断座位数是否>=1//是的话就直接减库存//不是就return 201，库存不够int k=0;FlightSeat seat = seatService.getById(selectFlightMap.get("seatId"));if(seat.getRestNum()<1){return new BaseResult(201,"库存不够了");}seat.setRestNum(seat.getRestNum()-1);boolean updateResult = seatService.updateById(seat);if(!updateResult){//如果更新失败//说明在更新前有其他人已经对该行剩余量进行了修改//就再试一次，先判断库存int maxRetries = 5; //最大重试次数int retryCount = 0;while (retryCount < maxRetries) {// 获取最新的座位信息FlightSeat updatedSeat = seatService.getById(selectFlightMap.get("seatId"));// 检查座位是否仍然可用if (updatedSeat.getRestNum() < 1) {return new BaseResult(201, "库存不够了");}// 尝试更新座位信息updatedSeat.setRestNum(updatedSeat.getRestNum() - 1);boolean retryUpdateResult = seatService.updateById(updatedSeat);// 检查更新操作的结果if (retryUpdateResult) {// 成功更新，生成订单，跳出循环k=1;break;} else {// 增加重试计数并进行下一次尝试retryCount++;}if (retryCount == maxRetries) {return new BaseResult(202, "更新失败，重试次数已达上限");}}}else {k =1;}if(k==1){//k=1说明库存成功减少了FlightOrder Order = new FlightOrder();// 获取当前时间LocalDateTime currentTime = LocalDateTime.now();// 如果你想以特定格式输出当前时间，可以使用 DateTimeFormatterDateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");String formattedCurrentTime = currentTime.format(formatter);Order.setDate(formattedCurrentTime);// 设置超时时间为当前时间的15分钟后LocalDateTime timeoutTime = currentTime.plusMinutes(15);String formattedTimeoutTime = timeoutTime.format(formatter);Order.setTimeout(formattedTimeoutTime);Order.setOrderId(String.valueOf(new SnowUtil(0,0).getId()));// redisTemplate.opsForValue().set(Order.getOrderId(), Order.getOrderId(), 15, TimeUnit.MINUTES);redisTemplate.opsForValue().set(Order.getOrderId(), Order.getOrderId(), 15, TimeUnit.MINUTES);Flight flight = new Flight();flight = flightService.getById(selectFlightMap.get("flightId"));Order.setFlightCode(flight.getFlightCode());Order.setStage("待支付");Order.setWay("单程");Order.setUserId(account);Air air = airService.getById(flight.getAirId());Order.setPrice(seat.getPrice());Order.setAllPrice(seat.getPrice());Order.setSeatType(seat.getSeatType());Order.setDepCity(flight.getDepCity());Order.setDepDate(flight.getDepDate());Order.setDepTime(flight.getDepTime());Order.setArrCity(flight.getArrCity());Order.setArrDate(flight.getArrDate());Order.setArrTime(flight.getArrTime());Order.setDepAirport(flight.getDepAirport());Order.setArrAirport(flight.getArrAirport());Order.setAirlineName(flight.getAirlineName());Order.setAirType(air.getType());orderService.save(Order);for (Map<String, String> pas : passengers) {FlightPassenger passenger = new FlightPassenger();passenger.setOrderId(Order.getOrderId());passenger.setName(pas.get("name"));passenger.setIdentityId(pas.get("sfz"));passenger.setPhone(pas.get("phone"));passengerService.save(passenger);}return new BaseResult(200,"支付成功",Order.getOrderId());}else return new BaseResult(202,"库存不够或者重试次数达到上限");}
往返票
@Transactionalpublic BaseResult creatTwoOrder(FlightOrderServiceImpl orderService,List<Map<String, String>> passengers,Map<String, String> selectFlightMap,String account) throws Exception {// 座位int k1=0,k2=0;FlightSeat seat = seatService.getById(selectFlightMap.get("goSeatId"));FlightSeat seatback = seatService.getById(selectFlightMap.get("backSeatId"));//先判断库存if(seat.getRestNum()<1||seatback.getRestNum()<1){return new BaseResult(201,"库存不够了");}//如果库存都够seat.setRestNum(seat.getRestNum()-1);boolean updateResult = seatService.updateById(seat);if(!updateResult){//如果更新失败int max =5;int cnt=0;while(cnt<max){//先判断库存FlightSeat newSeat = seatService.getById(selectFlightMap.get("goSeatId"));if(newSeat.getRestNum()<1){return new BaseResult(201,"库存不够了");}//如果库存足够newSeat.setRestNum(newSeat.getRestNum()-1);boolean updateSeatResult = seatService.updateById(newSeat);if(updateSeatResult){//成功k1 =1;break;}else {//修改库存又失败了，有其他线程已经将这行记录的值进行了修改cnt++;}if(cnt==max){return new BaseResult(202,"重试次数已经达到上限");}}}else {//一次成功k1 =1;}//到这里的话就说明去程的票减库存已经成功了//开始买返程的票seatback.setRestNum(seatback.getRestNum()-1);boolean backSeatResult = seatService.updateById(seatback);if(!backSeatResult){//如果更新失败int max1 =5;int cnt1 =0;while (cnt1<max1){FlightSeat newSeatback = seatService.getById(selectFlightMap.get("backSeatId"));if(newSeatback.getRestNum()<1){//回滚去程的票数TransactionAspectSupport.currentTransactionStatus().setRollbackOnly();return new BaseResult(202,"库存不够了");}//如果库存足够boolean result = seatService.updateById(newSeatback);if(result){k2=1;break;}else {cnt1++;}if(cnt1==max1){//首先要回滚去程的库存TransactionAspectSupport.currentTransactionStatus().setRollbackOnly();return new BaseResult(202,"达到尝试上限");}}}else {k2=1;}if(k1==1&&k2==1){FlightOrder Order = new FlightOrder();// 获取当前时间LocalDateTime currentTime = LocalDateTime.now();// 如果你想以特定格式输出当前时间，可以使用 DateTimeFormatterDateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");String formattedCurrentTime = currentTime.format(formatter);Order.setDate(formattedCurrentTime);// 设置超时时间为当前时间的15分钟后LocalDateTime timeoutTime = currentTime.plusMinutes(15);String formattedTimeoutTime = timeoutTime.format(formatter);Order.setTimeout(formattedTimeoutTime);Order.setOrderId(String.valueOf(new SnowUtil(0,0).getId()));redisTemplate.opsForValue().set(Order.getOrderId(), Order.getOrderId(), 15, TimeUnit.MINUTES);// 获取数据Flight flight1 = flightService.getById(selectFlightMap.get("goId"));Air air1 = airService.getById(flight1.getAirId());Order.setDepCity(flight1.getDepCity());Order.setDepDate(flight1.getDepDate());Order.setDepTime(flight1.getDepTime());Order.setArrCity(flight1.getArrCity());Order.setArrDate(flight1.getArrDate());Order.setArrTime(flight1.getArrTime());Order.setDepAirport(flight1.getDepAirport());Order.setArrAirport(flight1.getArrAirport());Order.setAirlineName(flight1.getAirlineName());Order.setAirType(air1.getType());// 订单对象Order.setFlightCode(flight1.getFlightCode());Order.setStage("待支付");Order.setWay("往返");Order.setUserId(account);Order.setPrice(seat.getPrice());Order.setSeatType(seat.getSeatType());Flight flight2 = flightService.getById(selectFlightMap.get("backId"));Air air2 = airService.getById(flight2.getAirId());Order.setBackDepCity(flight2.getDepCity());Order.setBackDepDate(flight2.getDepDate());Order.setBackDepTime(flight2.getDepTime());Order.setBackArrCity(flight2.getArrCity());Order.setBackArrDate(flight2.getArrDate());Order.setBackArrTime(flight2.getArrTime());Order.setBackDepAirport(flight2.getDepAirport());Order.setBackArrAirport(flight2.getArrAirport());Order.setBackAirlineName(flight2.getAirlineName());Order.setBackAirType(air2.getType());Order.setBackPrice(seatback.getPrice());Order.setAllPrice(seat.getPrice()+seatback.getPrice());Order.setBackFlightCode(flight2.getFlightCode());Order.setBackSeatType(seatback.getSeatType());orderService.save(Order);for (Map<String, String> pas : passengers) {FlightPassenger passenger = new FlightPassenger();passenger.setOrderId(Order.getOrderId());passenger.setName(pas.get("name"));passenger.setIdentityId(pas.get("sfz"));passenger.setPhone(pas.get("phone"));passengerService.save(passenger);}return new BaseResult(200,"支付成功",Order.getOrderId());}else {TransactionAspectSupport.currentTransactionStatus().setRollbackOnly();return new BaseResult(202, "库存不够或者达到重试次数上限");}}这篇关于乐观锁解决库存超卖问题的文章就介绍到这儿，希望我们推荐的文章对编程师们有所帮助！
