* Gets the user ID.
     *
     * @return the user ID
     */
    public String getUserId() {
        return userId;
    }

    /**
     * Sets the user ID.
     *
     * @param userId the user ID
     */
    public void setUserId(final String userId) {
        this.userId = userId;
    }

    /**
     * Gets the creation timestamp.
     *
     * @return the creation timestamp
     */

                // Validate userId matches - prevent cross-user session access
                if (userId != null && !userId.equals(sessionUserId)) {
                    logger.warn("Session userId mismatch. sessionId={}, requestUserId={}", sessionId, userId);
                } else if (userId == null && sessionUserId == null) {

            if (fields.isEmpty() && extraQueries.length == 0) {
                result = ComponentUtil.getChatClient().chat(sessionId, message, userId);
            } else {
                result = ComponentUtil.getChatClient().chat(sessionId, message, userId, fields, extraQueries);
            }

            if (logger.isDebugEnabled()) {

     * @param userMessage the user's message
     * @param userId the user ID (can be null for anonymous users)
     * @return the chat response including session info and sources
     */
    public ChatResult chat(final String sessionId, final String userMessage, final String userId) {
        return chat(sessionId, userMessage, userId, Collections.emptyMap(), new String[0]);
    }

    /**

        final String[] roles;
        final String userCode;
        final String userId;
        final HttpServletRequest request;
        final String clientIp;
        final String virtualHostKey;

        SearchLogContext(final FessConfig fessConfig, final String[] roles, final String userCode, final String userId,
                final HttpServletRequest request, final String clientIp, final String virtualHostKey) {

     * Note: If the first two characters are uppercase, the string will not be decapitalized.
     * <p>
     * Usage example:
     * </p>
     *
     * <pre>
     * StringUtil.decapitalize("UserId")  = "userId"
     * StringUtil.decapitalize("ABC")     = "ABC"
     * </pre>
     *
     * @param name
     *            the string to decapitalize
     * @return the decapitalized string
     */

| Constants | UPPER_SNAKE_CASE | `DEFAULT_PAGE_SIZE` |
| Fields | camelCase | `userPager`, `fessConfig` |

## Log Message Guidelines

- Logger: `LogManager.getLogger(ClassName.class)`
- Format: `key=value` (e.g., `userId={}`, `url={}`)
- Prefix with `[name]` when context identification is needed
- Mask sensitive values (passwords, tokens)

## i18n / Localization

        return new SearchLogHelper.SearchLogContext((FessConfig) ComponentUtil.getFessConfig(), new String[0], // roles
                null, // userCode
                null, // userId
                request, // request
                "127.0.0.1", // clientIp
                "" // virtualHostKey
        );
    }