@java.lang.Override
  public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io.IOException {
    for (int i = 0; i < buckets_.size(); i++) {
      output.writeMessage(1, buckets_.get(i));
    }
    getUnknownFields().writeTo(output);
  }
<pre>
Required. List of buckets and their objects to be transformed. Currently,
only one bucket configuration is supported. If multiple buckets are
specified, an error will be returned.
</pre>

<code>
repeated .google.cloud.storagebatchoperations.v1.BucketList.Bucket buckets = 1 [(.google.api.field_behavior) = REQUIRED];
</code>
java-storagebatchoperations/proto-google-cloud-storagebatchoperations-v1/src/main/java/com/google/cloud/storagebatchoperations/v1/BucketList.java