@java.lang.Override
  public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io.IOException {
    if (((bitField0_ & 0x00000001) != 0)) {
      output.writeMessage(1, getProductSet());
    }
    if (((bitField0_ & 0x00000002) != 0)) {
      output.writeMessage(2, getUpdateMask());
    }
    getUnknownFields().writeTo(output);
  }
<pre>
The [FieldMask][google.protobuf.FieldMask] that specifies which fields to
update.
If update_mask isn't specified, all mutable fields are to be updated.
Valid mask path is `display_name`.
</pre>

<code>.google.protobuf.FieldMask update_mask = 2;</code>
java-vision/proto-google-cloud-vision-v1p3beta1/src/main/java/com/google/cloud/vision/v1p3beta1/UpdateProductSetRequest.java