public Builder clearGcsDataSink() {
        if (gcsDataSinkBuilder_ == null) {
          if (dataSinkCase_ == 4) {
            dataSinkCase_ = 0;
            dataSink_ = null;
            onChanged();
          }
        } else {
          if (dataSinkCase_ == 4) {
            dataSinkCase_ = 0;
            dataSink_ = null;
          }
          gcsDataSinkBuilder_.clear();
        }
        return this;
      }
<pre>
A Cloud Storage data sink.
</pre>

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