ticker.advance(1, MILLISECONDS);
    assertThat(keySet).containsExactly(3, 4, 5, 6, 7, 8, 9, 0);

    // asMap.put saves 3
    cache.asMap().put(3, -3);
    ticker.advance(1, MILLISECONDS);
    assertThat(keySet).containsExactly(4, 5, 6, 7, 8, 9, 0, 3);

    // asMap.replace saves 4
    cache.asMap().replace(4, -4);
    ticker.advance(1, MILLISECONDS);
    assertThat(keySet).containsExactly(5, 6, 7, 8, 9, 0, 3, 4);

        if (logger.isDebugEnabled()) {
            logger.debug("Create thumbnail task: {}", task);
        }
        return task;
    }

    /**
     * Generates a thumbnail image and saves it to the specified output file.
     *
     * <p>This method processes the image content associated with the thumbnail ID,
     * validates the image format, applies scaling and cropping transformations,

    //                                                                        Small Helper
    //                                                                        ============

    /**
     * Saves informational messages to the session.
     * The messages will be displayed to the user on the next page load.
     *
     * @param validationMessagesLambda a lambda function to configure the messages
     */

    /**
     * Gets the name of this thumbnail generator.
     * @return The generator name.
     */
    String getName();

    /**
     * Generates a thumbnail for the given thumbnail ID and saves it to the output file.
     *
     * @param thumbnailId the unique identifier for the thumbnail
     * @param outputFile the file where the generated thumbnail will be saved

    /**
     * Polls a URL queue.
     *
     * @param sessionId The session ID.
     * @return The URL queue.
     */
    QUEUE poll(String sessionId);

    /**
     * Saves the session.
     *
     * @param sessionId The session ID.
     */
    void saveSession(String sessionId);

    /**
     * Checks if a URL has been visited.
     *
     * @param urlQueue The URL queue.

        // example to use remember-me
        //return OptionalThing.of(fessConfig.getCookieRememberMeFessKey());
        return OptionalThing.empty();
    }

    /**
     * Saves the login history for the given user.
     * This operation is performed asynchronously.
     *
     * @param user the user entity
     * @param userBean the user bean
     * @param option the login specified option

                .map(token -> ADMIN_SERVER + token)
                .orElseThrow(() -> new FessSystemException("Cannot create an access token."));
    }

    /**
     * Generates and saves a new access token for the current session.
     * The token is used to authenticate API requests.
     */
    public void saveToken() {

OkHttp
======

See the [project website][okhttp] for documentation and APIs.

HTTP is the way modern applications network. It’s how we exchange data & media. Doing HTTP
efficiently makes your stuff load faster and saves bandwidth.

OkHttp is an HTTP client that’s efficient by default:

 * HTTP/2 support allows all requests to the same host to share a socket.
 * Connection pooling reduces request latency (if HTTP/2 isn’t available).

     */
    @Override
    public void destroy() {
        destoryTimer.cancel();
        destoryTimer = null;
    }

    /**
     * Generates a thumbnail for the given ID and saves it to the output file.
     * @param thumbnailId The ID of the thumbnail to generate.
     * @param outputFile The file where the thumbnail will be saved.
     * @return True if thumbnail generation was successful, false otherwise.

                SortBuilders.fieldSort(OpenSearchUrlQueue.WEIGHT).order(SortOrder.DESC),
                SortBuilders.fieldSort(CREATE_TIME).order(SortOrder.ASC));
    }

    /**
     * Saves the session state (currently not implemented).
     *
     * @param sessionId The session ID.
     */
    @Override
    public void saveSession(final String sessionId) {
        // TODO use cache
    }