public List<ProxySelectorDataSubscriber> getProxySelectorDataSubscribers() {
        return proxySelectorDataSubscribers;
    }
get proxy selector data subscriber.

@return proxy selector data subscriber
shenyu-sync-data-center/shenyu-sync-data-websocket/src/main/java/org/apache/shenyu/plugin/sync/data/websocket/WebsocketSyncDataService.java