// No matching host header
        String key = virtualHostHelper.getVirtualHostKey();
        assertEquals("", key);

        // Matching host header
        request.addHeader("Host", "example.com");
        key = virtualHostHelper.getVirtualHostKey();
        assertEquals("", key); // Still empty due to caching

        // Test caching by calling again - should return cached value

        relatedQueryHelper.load();

        // Mock virtual host helper to return site1.com
        virtualHostHelper = new VirtualHostHelper() {
            @Override
            public String getVirtualHostKey() {
                return "site1.com";
            }
        };
        ComponentUtil.register(virtualHostHelper, "virtualHostHelper");

     */
    public void buildQuery(final List<String> keywordList, final List<FilterFunctionBuilder> list) {
        final String key = ComponentUtil.getVirtualHostHelper().getVirtualHostKey();
        keywordList.stream().forEach(keyword -> {
            final List<Tuple3<String, QueryBuilder, ScoreFunctionBuilder<?>>> boostList = getQueryMap(key).get(toLowerCase(keyword));
            if (boostList != null) {

        if (labelTypeItemList == null) {
            init();
        }

        final String virtualHostKey = ComponentUtil.getVirtualHostHelper().getVirtualHostKey();
        final List<LabelTypeItem> labelList;
        if (StringUtil.isBlank(virtualHostKey)) {
            labelList =

            return labelTypeList;
        }
    }

    private static class MockVirtualHostHelper extends VirtualHostHelper {
        @Override
        public String getVirtualHostKey() {
            return ""; // Return empty string for testing
        }
    }

    private static class MockRoleQueryHelper extends RoleQueryHelper {
        @Override

        // Mock virtual host helper to return empty key (different from host1)
        virtualHostHelper = new VirtualHostHelper() {
            @Override
            public String getVirtualHostKey() {
                return "";
            }
        };
        ComponentUtil.register(virtualHostHelper, "virtualHostHelper");

        String[] results = relatedContentHelper.getRelatedContents("test");

        if (fessConfig.isWebApiPopularWord()) {
            final List<String> tagList = new ArrayList<>();
            final String key = ComponentUtil.getVirtualHostHelper().getVirtualHostKey();
            if (StringUtil.isNotBlank(key)) {
                tagList.add(key);
            }
            runtime.registerData("popularWords", popularWordHelper.getWordList(SearchRequestType.SEARCH, null,

                    searchLog.addRequestHeaderValue(key, v);
                });
            }
        });

        final String virtualHostKey = ComponentUtil.getVirtualHostHelper().getVirtualHostKey();
        if (StringUtil.isNotBlank(virtualHostKey)) {
            searchLog.setVirtualHost(virtualHostKey);
        } else {
            searchLog.setVirtualHost(StringUtil.EMPTY);
        }

        switch (searchRequestType) {
        case ADMIN_SEARCH:
            // nothing to do
            break;
        default:
            final String key = ComponentUtil.getVirtualHostHelper().getVirtualHostKey();
            if (StringUtil.isNotBlank(key)) {
                queryContext.addQuery(boolQuery -> {