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我需要在成功处理并存储后，才能在兔子听众中手动确认多条消息。使用的弹簧启动配置如下SpringBoot：手动确认多个AMQP消息
listener:
concurrency: 2
max-concurrency: 20
acknowledge-mode: manual
prefetch: 30
消息应该一次存储20个批次。只有当它们被成功存储时，才应该发送多重确认。存储机制也存在关联超时，即使没有20个消息，也应在20秒后存储消息。目前，我有以下的代码
@Slf4j
@Component
class EventListener {
@Autowired
private EventsStorage eventsStorage
private ConcurrentMap<Integer, ChannelData> channelEvents = new ConcurrentHashMap<>()
@RabbitListener(queues = 'event-queue')
void processEvent(@Payload Event event, Channel channel, @Header(DELIVERY_TAG) long tag) {
log.debug("Event received for channel $channel.channelNumber")
channelEvents.compute(channel.channelNumber, { k, channelData -> addEventAndStoreIfNeeded(channel, event, tag, channelData) })
}
private ChannelData addEventAndStoreIfNeeded(Channel channel, Event event, long tag, ChannelData channelData) {
if (channelData) {
channelData.addEvent(tag, event)
if (channelData.getDeliveredEvents().size() >= batchSize) {
storeAndAckChannelEvents(channel.channelNumber)
}
return channelData
} else {
ChannelData newChannelData = new ChannelData(channel)
newChannelData.addEvent(tag, event)
return newChannelData
}
}
void storeAndAckChannelEvents(Integer channelNumber) {
channelEvents.compute(channelNumber, { k, channelData ->
List<DeliveredEvent> deliveredEvents = channelData.deliveredEvents
if (!deliveredEvents.isEmpty()) {
def events = deliveredEvents.stream()
.map({ DeliveredEvent deliveredEvent -> deliveredEvent.event })
.collect(Collectors.toList())
eventsStorage.store(events)
long lastDeliveryTag = deliveredEvents.get(deliveredEvents.size() - 1).deliveryTag
channelData.channel.basicAck(lastDeliveryTag, true)
deliveredEvents.clear()
}
})
}
@Scheduled(fixedRate = 20000L)
void storeMessagingEvents() {
channelEvents.forEach({ k, channelData -> storeAndAckChannelEvents(channelData) })
}
}
其中ChannelData和DeliveredEvent表现如下
class DeliveredMesssagingEvent {
int deliveryTag
Event event
}
class ChannelData {
Channel channel
List<DeliveredEvent> deliveredEvents = new ArrayList<>()
ChannelData(Channel channel) {
this.channel = channel
}
void addEvent(long tag, Event event) {
deliveredEvents.add(new DeliveredEvent(deliveryTag: tag, event: event))
}
}
使用的Channel是com.rabbitmq.client.Channel。关于此接口状态的The docs：
通道实例不能在线程之间共享。应用程序应该更喜欢使用每个线程的通道，而不是在多个线程之间共享同一个通道
所以，我做的非常相反，在Scheduler和SimpleMessageListenerContainer工作线程之间共享Channel。我的应用程序的输出是这样的：
[SimpleAsyncTaskExecutor-3] DEBUG EventListener - Event received for channel 2
[SimpleAsyncTaskExecutor-4] DEBUG EventListener - Event received for channel 3
[SimpleAsyncTaskExecutor-5] DEBUG EventListener - Event received for channel 1
[SimpleAsyncTaskExecutor-1] DEBUG EventListener - Event received for channel 5
[SimpleAsyncTaskExecutor-2] DEBUG EventListener - Event received for channel 4
[SimpleAsyncTaskExecutor-3] DEBUG EventListener - Event received for channel 2
[SimpleAsyncTaskExecutor-1] DEBUG EventListener - Event received for channel 5
[SimpleAsyncTaskExecutor-2] DEBUG EventListener - Event received for channel 4
[SimpleAsyncTaskExecutor-3] DEBUG EventListener - Event received for channel 2
[pool-4-thread-1] DEBUG EventListener - Storing channel 5 events
[pool-4-thread-1] DEBUG EventListener - Storing channel 2 events
...
SimpleMessageListenerContainer工作者线程有自己的通道，它不随时间而改变。
考虑到我同步Scheduler和SimpleMessageListenerContainer工作线程，有没有人看到任何理由为什么这个代码不是线程安全的？
是否有任何其他方法，我应该尝试在Spring启动时手动确认多条消息？