final SearchHits innerSearchHits = innerHits.get(fessConfig.getQueryCollapseInnerHitsName());
                        if (innerSearchHits != null) {
                            final long totalHits = innerSearchHits.getTotalHits().value();
                            if (totalHits > 1) {
                                docMap.put(fessConfig.getQueryCollapseInnerHitsName() + "_count", totalHits);

         */
        protected CollapseBuilder getCollapseBuilder(final FessConfig fessConfig) {
            final InnerHitBuilder innerHitBuilder = new InnerHitBuilder().setName(fessConfig.getQueryCollapseInnerHitsName())
                    .setSize(fessConfig.getQueryCollapseInnerHitsSizeAsInteger());
            fessConfig.getQueryCollapseInnerHitsSortBuilders()

     * comment: Inner hits name for collapse queries.
     * @return The value of found property. (NotNull: if not found, exception but basically no way)
     */
    String getQueryCollapseInnerHitsName();

    /**
     * Get the value for the key 'query.collapse.inner.hits.size'. <br>
     * The value is, e.g. 0 <br>
     * comment: Inner hits size for collapse queries.