@Test // INT-2090
public void jsonTypeIdNotOverwritten() {
SimpleAmqpHeaderMapper headerMapper = new SimpleAmqpHeaderMapper();
JsonMessageConverter converter = new JsonMessageConverter();
MessageProperties amqpProperties = new MessageProperties();
converter.toMessage("123", amqpProperties);
Map<String, Object> headerMap = new HashMap<String, Object>();
headerMap.put("__TypeId__", "java.lang.Integer");
MessageHeaders messageHeaders = new MessageHeaders(headerMap);
headerMapper.fromHeaders(messageHeaders, amqpProperties);
assertEquals("java.lang.String", amqpProperties.getHeaders().get("__TypeId__"));