public java.lang.String getRagCorpus() {
        java.lang.Object ref = ragCorpus_;
        if (!(ref instanceof java.lang.String)) {
          com.google.protobuf.ByteString bs = (com.google.protobuf.ByteString) ref;
          java.lang.String s = bs.toStringUtf8();
          ragCorpus_ = s;
          return s;
        } else {
          return (java.lang.String) ref;
        }
      }
<pre>
Optional. RagCorpora resource name.
Format:
`projects/{project}/locations/{location}/ragCorpora/{rag_corpus}`
</pre>

<code>
string rag_corpus = 1 [(.google.api.field_behavior) = OPTIONAL, (.google.api.resource_reference) = { ... }
</code>

@return The ragCorpus.
java-vertexai/proto-google-cloud-vertexai-v1/src/main/java/com/google/cloud/vertexai/api/VertexRagStore.java