private com.google.protobuf.SingleFieldBuilderV3<
            com.google.cloud.vertexai.api.GcsSource,
            com.google.cloud.vertexai.api.GcsSource.Builder,
            com.google.cloud.vertexai.api.GcsSourceOrBuilder>
        getGcsSourceFieldBuilder() {
      if (gcsSourceBuilder_ == null) {
        gcsSourceBuilder_ =
            new com.google.protobuf.SingleFieldBuilderV3<
                com.google.cloud.vertexai.api.GcsSource,
                com.google.cloud.vertexai.api.GcsSource.Builder,
                com.google.cloud.vertexai.api.GcsSourceOrBuilder>(
                getGcsSource(), getParentForChildren(), isClean());
        gcsSource_ = null;
      }
      return gcsSourceBuilder_;
    }
<pre>
Required. Google Cloud Storage location.
</pre>

<code>
.google.cloud.vertexai.v1.GcsSource gcs_source = 1 [(.google.api.field_behavior) = REQUIRED];
</code>
java-vertexai/proto-google-cloud-vertexai-v1/src/main/java/com/google/cloud/vertexai/api/AvroSource.java