private void deleteDoc(final IndexWriter writer, final DocRef docRef) {
        try {
            final Query query = createDocQuery(docRef, null);
            writer.deleteDocuments(query);
        } catch (final ParseException | IOException e) {
            LOGGER.error(e::getMessage, e);
        }
    }
Re-index all indexable items on the system
stroom-index/stroom-index-lucene980/src/main/java/stroom/contentindex/LuceneContentIndex.java