if (resolver instanceof AbstractMessageConverterMethodArgumentResolver) {
found = true;
AbstractMessageConverterMethodArgumentResolver processor = (AbstractMessageConverterMethodArgumentResolver) resolver;
List<HttpMessageConverter<?>> converters = (List<HttpMessageConverter<?>>) ReflectionTestUtils.getField(
processor, "messageConverters");
assertThat(converters.get(0), is(instanceOf(TypeConstrainedMappingJackson2HttpMessageConverter.class)));
assertThat(converters.get(0).getSupportedMediaTypes(), hasItem(MediaTypes.HAL_JSON));