public static Function<? super RpcService, BraveRpcService>
    newDecorator(Tracing tracing) {
        return newDecorator(RpcTracing.newBuilder(tracing)
                                      .serverRequestParser(defaultRequestParser)
                                      .serverResponseParser(defaultResponseParser)
                                      .build());
    }
Creates a new tracing {@link RpcService} decorator using the specified {@link Tracing} instance.
brave/brave6/src/main/java/com/linecorp/armeria/server/brave/BraveRpcService.java