*
     * <p>Supported parameters:</p>
     * <ul>
     * <li>encoding - Character encoding for request parameters</li>
     * <li>token_url - URL to request the token from</li>
     * <li>token_pattern - Regex pattern to extract the token</li>
     * <li>token_name - Name of the token parameter</li>
     * <li>token_method - HTTP method for token request (GET or POST)</li>