private Hbck getHbckInternal(ServerName masterServer) {
    Span.current().setAttribute(SERVER_NAME_KEY, masterServer.getServerName());
    // we will not create a new connection when creating a new protobuf stub, and for hbck there
    // will be no performance consideration, so for simplification we will create a new stub every
    // time instead of caching the stub here.
    return new HBaseHbck(MasterProtos.HbckService.newBlockingStub(
      rpcClient.createBlockingRpcChannel(masterServer, user, rpcTimeout)), rpcControllerFactory);
  }
If choreService has not been created yet, create the ChoreService.
hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncConnectionImpl.java