public Set<NewDocumentType> build(ModelElement documentsElement) {
        if (documentsElement == null || documentsElement.subElements("document").isEmpty())
            return Set.of();

        return documentsElement.subElements("document")
                .stream()
                .filter(GlobalDistributionBuilder::isGloballyDistributed)
                .map(GlobalDistributionBuilder::getDocumentName)
                .map(this::getDocumentType)
                .collect(Collectors.toCollection(LinkedHashSet::new));
    }
Determines the set of document types that are configured to be globally distributed.

@author bjorncs
config-model/src/main/java/com/yahoo/vespa/model/content/cluster/GlobalDistributionBuilder.java