@java.lang.Override
    public com.google.cloud.translate.v3.GcsInputSource getGcsInputSource() {
      if (gcsInputSourceBuilder_ == null) {
        if (sourceCase_ == 3) {
          return (com.google.cloud.translate.v3.GcsInputSource) source_;
        }
        return com.google.cloud.translate.v3.GcsInputSource.getDefaultInstance();
      } else {
        if (sourceCase_ == 3) {
          return gcsInputSourceBuilder_.getMessage();
        }
        return com.google.cloud.translate.v3.GcsInputSource.getDefaultInstance();
      }
    }
<pre>
Google Cloud Storage file source.
</pre>

<code>.google.cloud.translation.v3.GcsInputSource gcs_input_source = 3;</code>

@return The gcsInputSource.
java-translate/proto-google-cloud-translate-v3/src/main/java/com/google/cloud/translate/v3/ImportAdaptiveMtFileRequest.java