@Override
    public Set<DescriptiveTypeSignature> findDescriptiveTypes() {
        final Set<DescriptiveTypeSignature> collectedDescriptiveTypes = new HashSet<>();
        fields().forEach(f -> ServiceInfo.findDescriptiveTypes(collectedDescriptiveTypes, f.typeSignature()));
        return ImmutableSortedSet.copyOf(comparing(TypeSignature::name), collectedDescriptiveTypes);
    }
Returns a new {@link StructInfo} with the specified {@link DescriptionInfo}.
Returns {@code this} if this {@link StructInfo} has the same {@link DescriptionInfo}.
core/src/main/java/com/linecorp/armeria/server/docs/StructInfo.java