private void updateNodeTagsListBoxContents() {
        //noinspection SimplifyStreamApiCallChains
        final List<String> tagsList = NullSafe.stream(nodeTags)
                .sorted()
                .collect(Collectors.toList());
        final int documentCount = NullSafe.size(docRefs);
        nodeTagsFormGroup.setLabel(documentCount > 1
                ? "Tags to add to " + documentCount + " Documents"
                : "Document Tags");

        nodeTagsListBox.clear();
        for (final String string : tagsList) {
            nodeTagsListBox.addItem(string);
        }
        if (nodeTagsListBox.getItemCount() > 0) {
            nodeTagsListBox.setSelectedIndex(0);
            updateButtonStates();
        }
    }
@return Trimmed and lower-cased tag.
stroom-core-client/src/main/java/stroom/explorer/client/view/ExplorerNodeEditTagsViewImpl.java