@java.lang.Override
    public boolean hasVertexRagStore() {
      return sourceCase_ == 4;
    }
<pre>
Set to use data source powered by Vertex RAG store.
User data is uploaded via the VertexRagDataService.
</pre>

<code>.google.cloud.vertexai.v1.VertexRagStore vertex_rag_store = 4;</code>

@return Whether the vertexRagStore field is set.
java-vertexai/proto-google-cloud-vertexai-v1/src/main/java/com/google/cloud/vertexai/api/Retrieval.java