final FessConfig fessConfig = ComponentUtil.getFessConfig();
        maxDeleteDocumentCacheSize = fessConfig.getIndexerDataMaxDeleteCacheSizeAsInteger();
        maxRedirectCount = fessConfig.getIndexerDataMaxRedirectCountAsInteger();
    }

    /**
     * Creates a new fixed thread pool executor with the specified number of threads.
     *
     * @param nThreads the number of threads in the pool

     * @return The value of found property. (NotNull: if not found, exception but basically no way)
     * @throws NumberFormatException When the property is not integer.
     */
    Integer getIndexerDataMaxRedirectCountAsInteger();

    /**
     * Get the value for the key 'indexer.language.fields'. <br>
     * The value is, e.g. content,important_content,title <br>