public void initializeServer() {
        log.info("Initializing REST server");

        Slf4jRequestLogWriter slf4jRequestLogWriter = new Slf4jRequestLogWriter();
        slf4jRequestLogWriter.setLoggerName(RestServer.class.getCanonicalName());
        CustomRequestLog requestLog = new CustomRequestLog(slf4jRequestLogWriter, CustomRequestLog.EXTENDED_NCSA_FORMAT + " %{ms}T");
        jettyServer.setRequestLog(requestLog);

        /* Needed for graceful shutdown as per `setStopTimeout` documentation */
        StatisticsHandler statsHandler = new StatisticsHandler();
        statsHandler.setHandler(handlers);
        jettyServer.setHandler(statsHandler);
        jettyServer.setStopTimeout(GRACEFUL_SHUTDOWN_TIMEOUT_MS);
        jettyServer.setStopAtShutdown(true);

        try {
            jettyServer.start();
        } catch (Exception e) {
            throw new ConnectException("Unable to initialize REST server", e);
        }

        log.info("REST server listening at " + jettyServer.getURI() + ", advertising URL " + advertisedUrl());
        URI adminUrl = adminUrl();
        if (adminUrl != null)
            log.info("REST admin endpoints at " + adminUrl);
    }
Creates Jetty connector according to configuration
connect/runtime/src/main/java/org/apache/kafka/connect/runtime/rest/RestServer.java