方式一：Consumer设置exclusive
注意条件
-
作用于basic.consume
-
不支持quorum queue
当同时有A、B两个消费者调用basic.consume方法消费，并将exclusive设置为true时，第二个消费者会抛出异常：com.rabbitmq.client.AlreadyClosedException: channel is already closed due to channel error; protocol method: #method<channel.close>(reply-code=403, reply-text=ACCESS_REFUSED - queue 'test' in vhost '/' in exclusive use, class-id=60, method-id=20)
at com.rabbitmq.client.impl.AMQChannel.ensureIsOpen(AMQChannel.java:190)
at com.rabbitmq.client.impl.AMQChannel.rpc(AMQChannel.java:223)
at com.rabbitmq.client.impl.ChannelN.basicConsume(ChannelN.java:981)
at com.dms.rabbitmq.TopicSender.lambda$main$2(TopicSender.java:63)
at java.base/java.lang.Thread.run(Thread.java:840)
Spring AMQP 如何通过exclusive实现顺序消费：
核心逻辑：
while (!DirectMessageListenerContainer.this.started && isRunning()) {
this.cancellationLock.reset();
try {
for (String queue : queueNames) {
consumeFromQueue(queue);
}
}
catch (AmqpConnectException | AmqpIOException e) {
long nextBackOff = backOffExecution.nextBackOff();
if (nextBackOff < 0 || e.getCause() instanceof AmqpApplicationContextClosedException) {
DirectMessageListenerContainer.this.aborted = true;
shutdown();
this.logger.error("Failed to start container - fatal error or backOffs exhausted",
e);
this.taskScheduler.schedule(this::stop, Instant.now());
break;
}
this.logger.error("Error creating consumer; retrying in " + nextBackOff, e);
doShutdown();
try {
Thread.sleep(nextBackOff); // NOSONAR
}
catch (InterruptedException e1) {
Thread.currentThread().interrupt();
}
continue; // initialization failed; try again having rested for backOff-interval
}
DirectMessageListenerContainer.this.started = true;
DirectMessageListenerContainer.this.startedLatch.countDown();
}
- 抛出异常后，会重试
- 重试间隔、次数受recoveryInterval（默认无限）、recoveryBackOff控制
方式二：single active consumer
原理：
代码示例：
Channel ch = ...;
Map<String, Object> arguments = newHashMap<String, Object>();
arguments.put("x-single-active-consumer", true);
ch.queueDeclare("my-queue", false, false, false, arguments);
