private List<DocRef> getNodeDocRefs() {
        return NullSafe.stream(explorerNodes)
                .filter(Objects::nonNull)
                .map(ExplorerNode::getDocRef)
                .filter(Objects::nonNull)
                .collect(Collectors.toList());
    }
Presenter for editing the tags on a single node or adding tags to multiple nodes.
See {@link ExplorerNodeRemoveTagsPresenter} for tag removal on multiple nodes.
stroom-core-client/src/main/java/stroom/explorer/client/presenter/ExplorerNodeEditTagsPresenter.java