ParameterizedTypeReference<List<Integer>> intList = new ParameterizedTypeReference<List<Integer>>() {}; given(converter.canRead(intList.getType(), null, null)).willReturn(true); given(converter.getSupportedMediaTypes()).willReturn(Collections.singletonList(MediaType.TEXT_PLAIN)); given(converter.canWrite(String.class, String.class, null)).willReturn(true);