spring - MessageConversionException: Failed to convert message content

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I have a SpringBoot Application which makes use of Spring AMQP. At the moment I am implementing the receiver side of it using JavaConfig classes as directed by official Spring docs examples. However, I am receiving a MessageConversionException and the message is not even reaching my ClientHandler class to process the message. Here are the console logs for the incident:
Caused by: org.springframework.amqp.support.converter.MessageConversionException: Failed to      convert Message content
    at org.springframework.amqp.support.converter.JsonMessageConverter.fromMessage(JsonMessageConverter.java:105) ~[spring-amqp-1.4.6.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.adapter.AbstractAdaptableMessageListener.extractMessage(AbstractAdaptableMessageListener.java:185) ~[spring-rabbit-1.4.6.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.adapter.MessageListenerAdapter.onMessage(MessageListenerAdapter.java:243) ~[spring-rabbit-1.4.6.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.doInvokeListener(AbstractMessageListenerContainer.java:756) ~[spring-rabbit-1.4.6.RELEASE.jar:na]
    ... 10 common frames omitted
Caused by: org.codehaus.jackson.map.JsonMappingException: Can not deserialize instance of byte out of START_OBJECT token
 at [Source: java.io.StringReader@33b39883; line: 1, column: 1]
    at org.codehaus.jackson.map.JsonMappingException.from(JsonMappingException.java:163) ~[jackson-mapper-asl-1.9.13.jar:1.9.13]
    at org.codehaus.jackson.map.deser.StdDeserializationContext.mappingException(StdDeserializationContext.java:219) ~[jackson-mapper-asl-1.9.13.jar:1.9.13]
    at org.codehaus.jackson.map.deser.std.StdDeserializer._parseByte(StdDeserializer.java:214) ~[jackson-mapper-asl-1.9.13.jar:1.9.13]
    at org.codehaus.jackson.map.deser.std.StdDeserializer$ByteDeserializer.deserialize(StdDeserializer.java:749) ~[jackson-mapper-asl-1.9.13.jar:1.9.13]
    at org.codehaus.jackson.map.deser.std.StdDeserializer$ByteDeserializer.deserialize(StdDeserializer.java:736) ~[jackson-mapper-asl-1.9.13.jar:1.9.13]
    at org.codehaus.jackson.map.ObjectMapper._readMapAndClose(ObjectMapper.java:2732) ~[jackson-mapper-asl-1.9.13.jar:1.9.13]
    at org.codehaus.jackson.map.ObjectMapper.readValue(ObjectMapper.java:1877) ~[jackson-mapper-asl-1.9.13.jar:1.9.13]
    at org.springframework.amqp.support.converter.JsonMessageConverter.convertBytesToObject(JsonMessageConverter.java:131) ~[spring-amqp-1.4.6.RELEASE.jar:na]
    at org.springframework.amqp.support.converter.JsonMessageConverter.fromMessage(JsonMessageConverter.java:100) ~[spring-amqp-1.4.6.RELEASE.jar:na]
    ... 13 common frames omitted
2016-10-25 12:51:42,020 WARN  t:[SimpleAsyncTaskExecutor-1] ConditionalRejectingErrorHandler: Fatal message conversion error; message rejected; it will be dropped or routed to a dead letter exchange, if so configured: (Body:'{"messageDTOList":[{"createdDate":1477396301061,"message":"{\"mac\":-99,\"device\":444,\"ifindex\":55,\"ip\":668,\"arpdevice\":99,\"aprifindex\":\"\",\"vlanindex\":111,\"enddevice\":133}","crudOperation":"UPDATE"}],"senderServerId":"5b36a7a1-c17d-471f-b16e-e8e0bf4afb5b","messageId":"5b36a7a1-c17d-471f-b16e-e8e0bf4afb5b20","rebasoftServerType":"AC","taskType":"MAC"}'MessageProperties [headers={}, timestamp=null, messageId=null, userId=null, appId=null, clusterId=null, type=null, correlationId=[53, 98, 51, 54, 97, 55, 97, 49, 45, 99, 49, 55, 100, 45, 52, 55, 49, 102, 45, 98, 49, 54, 101, 45, 101, 56, 101, 48, 98, 102, 52, 97, 102, 98, 53, 98, 50, 48], replyTo=null, contentType=application/json, contentEncoding=null, contentLength=0, deliveryMode=PERSISTENT, expiration=null, priority=0, redelivered=false, receivedExchange=X, receivedRoutingKey=data.core.macs, deliveryTag=2, messageCount=0])
org.springframework.amqp.rabbit.listener.exception.ListenerExecutionFailedException: Listener threw exception
    at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.wrapToListenerExecutionFailedExceptionIfNeeded(AbstractMessageListenerContainer.java:864) ~[spring-rabbit-1.4.6.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.doInvokeListener(AbstractMessageListenerContainer.java:759) ~[spring-rabbit-1.4.6.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.invokeListener(AbstractMessageListenerContainer.java:679) ~[spring-rabbit-1.4.6.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.access$001(SimpleMessageListenerContainer.java:83) [spring-rabbit-1.4.6.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer$1.invokeListener(SimpleMessageListenerContainer.java:170) ~[spring-rabbit-1.4.6.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.invokeListener(SimpleMessageListenerContainer.java:1253) [spring-rabbit-1.4.6.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.executeListener(AbstractMessageListenerContainer.java:660) ~[spring-rabbit-1.4.6.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.doReceiveAndExecute(SimpleMessageListenerContainer.java:1021) [spring-rabbit-1.4.6.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.receiveAndExecute(SimpleMessageListenerContainer.java:1005) [spring-rabbit-1.4.6.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.access$700(SimpleMessageListenerContainer.java:83) [spring-rabbit-1.4.6.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer$AsyncMessageProcessingConsumer.run(SimpleMessageListenerContainer.java:1115) [spring-rabbit-1.4.6.RELEASE.jar:na]
    at java.lang.Thread.run(Thread.java:745) [na:1.8.0_51]
Caused by: org.springframework.amqp.support.converter.MessageConversionException: Failed to convert Message content
    at org.springframework.amqp.support.converter.JsonMessageConverter.fromMessage(JsonMessageConverter.java:105) ~[spring-amqp-1.4.6.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.adapter.AbstractAdaptableMessageListener.extractMessage(AbstractAdaptableMessageListener.java:185) ~[spring-rabbit-1.4.6.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.adapter.MessageListenerAdapter.onMessage(MessageListenerAdapter.java:243) ~[spring-rabbit-1.4.6.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.doInvokeListener(AbstractMessageListenerContainer.java:756) ~[spring-rabbit-1.4.6.RELEASE.jar:na]
    ... 10 common frames omitted
Caused by: org.codehaus.jackson.map.JsonMappingException: Can not deserialize instance of byte out of START_OBJECT token
 at [Source: java.io.StringReader@33b39883; line: 1, column: 1]
    at org.codehaus.jackson.map.JsonMappingException.from(JsonMappingException.java:163) ~[jackson-mapper-asl-1.9.13.jar:1.9.13]
    at org.codehaus.jackson.map.deser.StdDeserializationContext.mappingException(StdDeserializationContext.java:219) ~[jackson-mapper-asl-1.9.13.jar:1.9.13]
    at org.codehaus.jackson.map.deser.std.StdDeserializer._parseByte(StdDeserializer.java:214) ~[jackson-mapper-asl-1.9.13.jar:1.9.13]
    at org.codehaus.jackson.map.deser.std.StdDeserializer$ByteDeserializer.deserialize(StdDeserializer.java:749) ~[jackson-mapper-asl-1.9.13.jar:1.9.13]
    at org.codehaus.jackson.map.deser.std.StdDeserializer$ByteDeserializer.deserialize(StdDeserializer.java:736) ~[jackson-mapper-asl-1.9.13.jar:1.9.13]
    at org.codehaus.jackson.map.ObjectMapper._readMapAndClose(ObjectMapper.java:2732) ~[jackson-mapper-asl-1.9.13.jar:1.9.13]
    at org.codehaus.jackson.map.ObjectMapper.readValue(ObjectMapper.java:1877) ~[jackson-mapper-asl-1.9.13.jar:1.9.13]
    at org.springframework.amqp.support.converter.JsonMessageConverter.convertBytesToObject(JsonMessageConverter.java:131) ~[spring-amqp-1.4.6.RELEASE.jar:na]
    at org.springframework.amqp.support.converter.JsonMessageConverter.fromMessage(JsonMessageConverter.java:100) ~[spring-amqp-1.4.6.RELEASE.jar:na]
    ... 13 common frames omitted
My client classes are below: 
AbstractEMCRabbitConfiguration.java
@Configuration
public abstract class AbstractEMCRabbitConfiguration {
//@Value("${emc.rabbit.exchange.core}")
protected static String CORE_DATA_EXCHANGE_NAME = "X";
@Value("${emc.rabbit.queue.core.macs}")
protected static String MAC_REQUEST_QUEUE_NAME = "data.core.macs";
protected static String MAC_REQUEST_ROUTING_KEY = MAC_REQUEST_QUEUE_NAME;
//@Value("${emc.rabbit.hostname}")
protected String hostname;
//@Value("${emc.rabbit.username}")
protected String username;
//@Value("${emc.rabbit.password}")
protected String password;
//@Value("${emc.rabbit.port:5672}")
protected Integer port = 5672;
protected abstract void configureRabbitTemplate(RabbitTemplate template);
@Bean
public ConnectionFactory connectionFactory(){
    CachingConnectionFactory connectionFactory = new CachingConnectionFactory("localhost");
    connectionFactory.setUsername("test");
    connectionFactory.setPassword("test");
    connectionFactory.setPort(port);
    connectionFactory.setRequestedHeartBeat(60);
    return connectionFactory;
@Bean
public RabbitTemplate rabbitTemplate(){
    RabbitTemplate template = new RabbitTemplate(connectionFactory());
    template.setMessageConverter(jsonMessageConverter());
    configureRabbitTemplate(template);
    return template;
@Bean
public MessageConverter jsonMessageConverter() {
    JsonMessageConverter jsonMessageConverter = new JsonMessageConverter();
    jsonMessageConverter.setClassMapper(defaultClassMapper());
    return jsonMessageConverter;
@Bean
public DefaultClassMapper defaultClassMapper() {
    DefaultClassMapper defaultClassMapper = new DefaultClassMapper();
    defaultClassMapper.setDefaultType(byte.class);
    return defaultClassMapper;
@Bean
public DirectExchange coreDataExchange() { return new DirectExchange(CORE_DATA_EXCHANGE_NAME); }
@Bean
public AmqpAdmin amqpAdmin() {
    RabbitAdmin rabbitAdmin = new RabbitAdmin(connectionFactory());
    return rabbitAdmin;
RabbitClientConfiguration.java
@Configuration
@Import({JacksonConfiguration.class, MessagingConfiguration.class})
public class RabbitClientConfiguration extends AbstractEMCRabbitConfiguration {
@Inject
private JacksonConfiguration jacksonConfiguration;
@Inject
private MessagingConfiguration messagingConfiguration;
//@Value("${data.core.pattern}")
//private String coreDataRoutingKey;
//@Inject
//private ClientHandler clientHandler;
@Override
public void configureRabbitTemplate(RabbitTemplate rabbitTemplate) {
    rabbitTemplate.setRoutingKey("data.core.macs");
@Bean
public SimpleMessageListenerContainer messageListenerContainer(){
    SimpleMessageListenerContainer container = new SimpleMessageListenerContainer();
    container.setConnectionFactory(connectionFactory());
    container.setQueues(macsDataQueue());
    container.setMessageListener(messageListenerAdapter());
    container.setAcknowledgeMode(AcknowledgeMode.AUTO);
    return container;
@Bean
MessageListenerAdapter messageListenerAdapter(){
    return new MessageListenerAdapter(clientHandler(jacksonConfiguration.objectMapper(),messagingConfiguration.macMessageHandler(messagingConfiguration.messagingFactory())),jsonMessageConverter());
    //return new MessageListenerAdapter(clientHandler,"receiveMessage");
@Bean
ClientHandler clientHandler(ObjectMapper objectMapper, IMessageHandler macMessageHandler){
    ClientHandler clientHandler = new ClientHandler();
    clientHandler.setObjectMapper(objectMapper);
    clientHandler.setMacMessageHandler(macMessageHandler);
    return clientHandler;
@Bean
public Queue macsDataQueue(){
    return rabbitAdmin().declareQueue();
@Bean
public Binding macsDataBinding(){
    return BindingBuilder.bind(macsDataQueue()).to(coreDataExchange()).with("data.core.macs");
@Bean
public AmqpAdmin rabbitAdmin() { return new RabbitAdmin(connectionFactory());}
A typical message received from the broker would look like this:
  (Body:'{"messageDTOList":[{"createdDate":1477396301061,"message":"{\"mac\":-99,\"device\":444,\"ifindex\":55,\"ip\":668,\"arpdevice\":99,\"aprifindex\":\"\",\"vlanindex\":111,\"enddevice\":133}","crudOperation":"UPDATE"}],"senderServerId":"5b36a7a1-c17d-471f-b16e-e8e0bf4afb5b","messageId":"5b36a7a1-c17d-471f-b16e-e8e0bf4afb5b20","rebasoftServerType":"AC","taskType":"MAC"}'MessageProperties [headers={}, timestamp=null, messageId=null, userId=null, appId=null, clusterId=null, type=null, correlationId=[53, 98, 51, 54, 97, 55, 97, 49, 45, 99, 49, 55, 100, 45, 52, 55, 49, 102, 45, 98, 49, 54, 101, 45, 101, 56, 101, 48, 98, 102, 52, 97, 102, 98, 53, 98, 50, 48], replyTo=null, contentType=application/json, contentEncoding=null, contentLength=0, deliveryMode=PERSISTENT, expiration=null, priority=0, redelivered=false, receivedExchange=X, receivedRoutingKey=data.core.macs, deliveryTag=2, messageCount=0])
Note: The content type is 'application/json'
Any help would me much appreciated.
  Caused by: org.codehaus.jackson.map.JsonMappingException: Can not deserialize instance of byte out of START_OBJECT token
Looks like a garbage message - are you sure it was created by the rabbit template with the json converter?
Can you edit the question and post the message content (and the content_type property, and other headers)? (You can use the Admin UI to examine the message).
I had no problems decoding your message with this app...
@SpringBootApplication
public class So40240771Application {
    public static void main(String[] args) throws Exception {
        ConfigurableApplicationContext context = SpringApplication.run(So40240771Application.class, args);
        RabbitTemplate template = context.getBean(RabbitTemplate.class);
        String body = "{"
                + "\"messageDTOList\":"
                + "[{\"createdDate\":1477396301061,"
                +   "\"message\":\"{\\\"mac\\\":-99,\\\"device\\\":444,\\\"ifindex\\\":55,\\\"ip\\\":668,\\\"arpdevice\\\":99,\\\"aprifindex\\\":\\\"\\\",\\\"vlanindex\\\":111,\\\"enddevice\\\":133}\","
                +   "\"crudOperation\":\"UPDATE\"}],"
                + "\"senderServerId\":\"5b36a7a1-c17d-471f-b16e-e8e0bf4afb5b\","
                + "\"messageId\":\"5b36a7a1-c17d-471f-b16e-e8e0bf4afb5b20\","
                + "\"rebasoftServerType\":\"AC\","
                + "\"taskType\":\"MAC\""
                + "}";
        MessageProperties properties = new MessageProperties();
        properties.setContentType("application/json");
        template.send("foo", MessageBuilder.withBody(body.getBytes()).andProperties(properties).build());
        Thread.sleep(6000);
        context.close();
    @Bean
    public Jackson2JsonMessageConverter converter() {
        Jackson2JsonMessageConverter converter = new Jackson2JsonMessageConverter();
        return converter;
    @Bean
    public SimpleMessageListenerContainer container(ConnectionFactory connectionFactory) {
        SimpleMessageListenerContainer container = new SimpleMessageListenerContainer(connectionFactory);
        container.setMessageListener(new MessageListenerAdapter(new Object() {
            void handleMessage(Object in) {
                System.out.println(in.getClass() + "\n" + in);
        }, converter()));
        container.setQueueNames("foo");
        return container;
Result:
class java.util.LinkedHashMap
{messageDTOList=[{createdDate=1477396301061, message={"mac":-99,"device":444,"ifindex":55,"ip":668,"arpdevice":99,"aprifindex":"","vlanindex":111,"enddevice":133}, crudOperation=UPDATE}], senderServerId=5b36a7a1-c17d-471f-b16e-e8e0bf4afb5b, messageId=5b36a7a1-c17d-471f-b16e-e8e0bf4afb5b20, rebasoftServerType=AC, taskType=MAC}
A couple of things to note: Since the message has no type information in the headers (which would have been added by the outbound converter if it was used) the message is decoded to a simple Map.
If you want to decode to an object, you either need the type information in the headers, or you need to configure the converter with a class mapper (such as the DefaultClassMapper.
Second, it looks like the "message" element is double-encoded JSON - it's already JSON and has been re-encoded).
                The provider side has its code written in java and I don't mind receiving it as a simple map. I have tried using the DefaultClassMapper as per the code but to no avail. I was wondering if a non-spring producer needs to provide header info as mandatory to a spring consumer?
– D.Kaushish
                Oct 25, 2016 at 16:07
                This is your problem jsonMessageConverter.setClassMapper(defaultClassMapper()); and  defaultClassMapper.setDefaultType(byte.class); you are trying to decode the JSON as a single byte. Just remove that class mapper and you'll get a Map.
– Gary Russell
                Oct 25, 2016 at 17:17
                I've got it working with that code still in there, though it may not be necessary. As mentioned below,  the main issue was the way I was wiring the MessageListenerAdapter.
– D.Kaushish
                Oct 27, 2016 at 8:37
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