@Nullable
    @Override
    public Boolean isResponseStreaming(Type returnType, @Nullable MediaType produceType) {
        final Class<?> clazz = typeToClass(unwrapUnaryAsyncType(returnType));
        if (clazz == null) {
            return null;
        }
        if (JsonNode.class.isAssignableFrom(clazz)) {
            return false;
        }
        if (produceType != null) {
            if (produceType.isJson()) {
                return false;
            }

            if (produceType.is(MediaType.JSON_SEQ) &&
                (Publisher.class.isAssignableFrom(clazz) || Stream.class.isAssignableFrom(clazz))) {
                return true;
            }
        }
        return null;
    }
Creates an instance with the specified {@link ObjectMapper}.
core/src/main/java/com/linecorp/armeria/server/annotation/JacksonResponseConverterFunction.java