@java.lang.Override
  public int getSerializedSize() {
    int size = memoizedSize;
    if (size != -1) return size;

    size = 0;
    if (requestCase_ == 1) {
      size +=
          com.google.protobuf.CodedOutputStream.computeMessageSize(
              1, (com.google.cloud.visionai.v1.Packet) request_);
    }
    if (requestCase_ == 2) {
      size +=
          com.google.protobuf.CodedOutputStream.computeMessageSize(
              2, (com.google.cloud.visionai.v1.RequestMetadata) request_);
    }
    size += getUnknownFields().getSerializedSize();
    memoizedSize = size;
    return size;
  }
<pre>
The first message of the streaming rpc including the request metadata.
</pre>

<code>.google.cloud.visionai.v1.RequestMetadata metadata = 2;</code>
java-visionai/proto-google-cloud-visionai-v1/src/main/java/com/google/cloud/visionai/v1/SendPacketsRequest.java