Genereally this comes into the picture when we use JsonMessageConverter for sending and receiving message in RabbitMQ.
We generally get Message object (org.springframework.amqp.core.Message) in onMessage(Message message) of receiver which is of form JSON. To get the desired value from this JSON object use this code in listener i.e. onMessage(Message message) of receiver
JsonMessageConverter jmc = new JsonMessageConverter();
TestUser u = (TestUser)jmc.fromMessage(message);
System.out.println("received: " + u.getName());