}
        return value;
    }

    String get(String propertyKey);

    String getSearchEngineType();

    default String getFesenType() {
        final String value = getSearchEngineType();
        if (value != null) {
            return value;
        }
        return get("elasticsearch.type");
    }

     * comment: The type of search engine backend (e.g., default, opensearch).
     * @return The value of found property. (NotNull: if not found, exception but basically no way)
     */
    String getSearchEngineType();

    /**
     * Get the value for the key 'search_engine.http.url'. <br>
     * The value is, e.g. http://localhost:9201 <br>
     * comment: <br>