@Override
	protected void onInit() {
		if (null == mqProducerProperties || !mqProducerProperties.getEnabled()) {
			return;
		}
		super.onInit();
		this.defaultMQProducer = RocketMQProduceFactory
				.initRocketMQProducer(destination.getName(), mqProducerProperties);
		this.isTrans = defaultMQProducer instanceof TransactionMQProducer;
		// Use the default if the partition is on and no customization is available.
		this.messageQueueSelector = RocketMQBeanContainerCache.getBean(
				mqProducerProperties.getMessageQueueSelector(),
				MessageQueueSelector.class,
				extendedProducerProperties.isPartitioned()
						? new PartitionMessageQueueSelector()
						: null);
	}
@author <a href="mailto:fangjian0423@gmail.com">Jim</a>
spring-cloud-alibaba-starters/spring-cloud-starter-stream-rocketmq/src/main/java/com/alibaba/cloud/stream/binder/rocketmq/integration/outbound/RocketMQProducerMessageHandler.java