// Fesen Client
    //

    /**
     * Gets the thread pool used by the client.
     *
     * @return the thread pool
     */
    @Override
    public ThreadPool threadPool() {
        return client.threadPool();
    }

    /**
     * Gets the admin client for cluster and index administration.
     *
     * @return the admin client
     */
    @Override

            { "aliases", "allocation", "count", "fielddata", "health", "indices", "master", "nodeattrs", "nodes", "pending_tasks",
                    "plugins", "recovery", "repositories", "thread_pool", "shards", "segments", "snapshots", "templates" };

    // ===================================================================================

    /**
     * Get the value for the key 'crawler.http.thread_pool.size'. <br>
     * The value is, e.g. 0 <br>
     * comment: Number of threads for HTTP crawling.
     * @return The value of found property. (NotNull: if not found, exception but basically no way)
     */
    String getCrawlerHttpThreadPoolSize();

    /**
     * Get the value for the key 'crawler.http.thread_pool.size' as {@link Integer}. <br>

# common

# Default script for the crawler (e.g., groovy).
crawler.default.script=groovy
# Number of threads for HTTP crawling.
crawler.http.thread_pool.size=0
# Serializer type for crawler data (e.g., kryo).
crawler.data.serializer=kryo
# Maximum length of site name in documents.
crawler.document.max.site.length=100
# Encoding for site names in documents.