private com.google.protobuf.SingleFieldBuilderV3<
              com.google.storagetransfer.v1.proto.TransferTypes.TransferOptions,
              com.google.storagetransfer.v1.proto.TransferTypes.TransferOptions.Builder,
              com.google.storagetransfer.v1.proto.TransferTypes.TransferOptionsOrBuilder>
          getTransferOptionsFieldBuilder() {
        if (transferOptionsBuilder_ == null) {
          transferOptionsBuilder_ =
              new com.google.protobuf.SingleFieldBuilderV3<
                  com.google.storagetransfer.v1.proto.TransferTypes.TransferOptions,
                  com.google.storagetransfer.v1.proto.TransferTypes.TransferOptions.Builder,
                  com.google.storagetransfer.v1.proto.TransferTypes.TransferOptionsOrBuilder>(
                  getTransferOptions(), getParentForChildren(), isClean());
          transferOptions_ = null;
        }
        return transferOptionsBuilder_;
      }
<pre>
Specifies the metadata options to be applied during replication.
Delete options are not supported. If a delete option is specified, the
request fails with an [INVALID_ARGUMENT][google.rpc.Code.INVALID_ARGUMENT]
error.
</pre>

<code>.google.storagetransfer.v1.TransferOptions transfer_options = 4;</code>
java-storage-transfer/proto-google-cloud-storage-transfer-v1/src/main/java/com/google/storagetransfer/v1/proto/TransferTypes.java