public Builder clearGcsDataSource() {
        if (gcsDataSourceBuilder_ == null) {
          if (dataSourceCase_ == 1) {
            dataSourceCase_ = 0;
            dataSource_ = null;
            onChanged();
          }
        } else {
          if (dataSourceCase_ == 1) {
            dataSourceCase_ = 0;
            dataSource_ = null;
          }
          gcsDataSourceBuilder_.clear();
        }
        return this;
      }
<pre>
The Cloud Storage bucket from which to replicate objects.
</pre>

<code>.google.storagetransfer.v1.GcsData gcs_data_source = 1;</code>
java-storage-transfer/proto-google-cloud-storage-transfer-v1/src/main/java/com/google/storagetransfer/v1/proto/TransferTypes.java