private void maybeOverrideRebalanceTimeout(short version) {
        if (version == 0) {
            // Version 0 has no rebalance timeout, so we use the session timeout
            // to be consistent with the original behavior of the API.
            data.setRebalanceTimeoutMs(data.sessionTimeoutMs());
        }
    }
Get the client's join reason.

@param request The JoinGroupRequest.

@return The join reason.
clients/src/main/java/org/apache/kafka/common/requests/JoinGroupRequest.java