public com.google.common.util.concurrent.ListenableFuture<com.google.protobuf.Empty>
        batchWriteSpans(com.google.devtools.cloudtrace.v2.BatchWriteSpansRequest request) {
      return io.grpc.stub.ClientCalls.futureUnaryCall(
          getChannel().newCall(getBatchWriteSpansMethod(), getCallOptions()), request);
    }
<pre>
Batch writes new spans to new or existing traces. You cannot update
existing spans.
</pre>
java-trace/grpc-google-cloud-trace-v2/src/main/java/com/google/devtools/cloudtrace/v2/TraceServiceGrpc.java