@Nullable
    private ObjectReader getObjectReader(Class<?> expectedResultType,
                                         @Nullable ParameterizedType expectedParameterizedResultType) {
        if (expectedParameterizedResultType != null) {
            return readers.computeIfAbsent(expectedParameterizedResultType, type -> {
                return mapper.readerFor(new TypeReference<Object>() {
                    @Override
                    public Type getType() {
                        return type;
                    }
                });
            });
        }

        return readers.computeIfAbsent(expectedResultType, type -> mapper.readerFor((Class<?>) type));
    }
Converts the specified {@link AggregatedHttpRequest} to an object of {@code expectedResultType}.
core/src/main/java/com/linecorp/armeria/server/annotation/JacksonRequestConverterFunction.java