Batching RabbitListener not working List<Message<Object>> messages

[adityaparikh91087]

Had a Spring Amqp Question. When enabling batching

    @Bean
    public RabbitListenerContainerFactory<?> batchContainerFactory(ConnectionFactory connectionFactory) {
        SimpleRabbitListenerContainerFactory factory = new SimpleRabbitListenerContainerFactory();
        factory.setConnectionFactory(connectionFactory);
        factory.setAcknowledgeMode(AcknowledgeMode.MANUAL); // Enable manual acknowledgement
        factory.setBatchListener(true);
        factory.setBatchSize(1024); // Set the number of messages to be received in a batch
        factory.setDeBatchingEnabled(false);
        return factory;
    }
 @RabbitListener(queues = "#{queue.getName()}", containerFactory = "batchContainerFactory")
    public void handleBatch(List<Message<Object>> messages, Channel channel) throws IOException {}.

In the RabbitListener I directly get the payload of the message
and get class java.lang.String cannot be cast to class org.springframework.messaging.Message (java.lang.String is in module java.base of loader 'bootstrap'; org.springframework.messaging.Message is in unnamed module of loader 'app') Tried with Spring boot 2.7 as well as 3.1.5

[garyrussell]

You also need to set consumerBatchEnabled to enable batching.

factory.setConsumerBatchEnabled(true);

	/**
	 * Set to true to present a list of messages based on the {@link #setBatchSize(Integer)},
	 * if the listener supports it. Starting with version 3.0, setting this to true will
	 * also {@link #setBatchListener(boolean)} to true.
	 * @param consumerBatchEnabled true to create message batches in the container.
	 * @since 2.2
	 * @see #setBatchSize(Integer)
	 * @see #setBatchListener(boolean)
	 */
	public void setConsumerBatchEnabled(boolean consumerBatchEnabled) {

[adityaparikh91087]

Thanks @garyrussell This got me past the cast error. However, the Batch Listener seems to be doing escaping that the regular listener is not.
expected: <{"ticker":"ABC"}> but was: <"{"ticker":"ABC"}">
For a simple test object record Trade(String ticker){};

[garyrussell]

That doesn't make any sense to me; what happens if you consume List<Object> ?

Can you show a screenshot of a message from the RabbitMQ management console?

[adityaparikh91087]

byte[] worked. I had to override the RabbitTemplate and RabbitMessagingTemplate for my test as I was overriding the MessageConverter.