@Override
    protected String usage() {
        return "ConnectStandalone worker.properties [connector1.properties connector2.json ...]";
    }
<p>
Command line utility that runs Kafka Connect as a standalone process. In this mode, work (connectors and tasks) is not
distributed. Instead, all the normal Connect machinery works within a single process. This is useful for ad hoc,
small, or experimental jobs.
</p>
<p>
Connector and task configs are stored in memory and are not persistent. However, connector offset data is persistent
since it uses file storage (configurable via {@link StandaloneConfig#OFFSET_STORAGE_FILE_FILENAME_CONFIG})
</p>
connect/runtime/src/main/java/org/apache/kafka/connect/cli/ConnectStandalone.java