private com.google.protobuf.SingleFieldBuilderV3<
            com.google.cloud.vertexai.api.SearchEntryPoint,
            com.google.cloud.vertexai.api.SearchEntryPoint.Builder,
            com.google.cloud.vertexai.api.SearchEntryPointOrBuilder>
        getSearchEntryPointFieldBuilder() {
      if (searchEntryPointBuilder_ == null) {
        searchEntryPointBuilder_ =
            new com.google.protobuf.SingleFieldBuilderV3<
                com.google.cloud.vertexai.api.SearchEntryPoint,
                com.google.cloud.vertexai.api.SearchEntryPoint.Builder,
                com.google.cloud.vertexai.api.SearchEntryPointOrBuilder>(
                getSearchEntryPoint(), getParentForChildren(), isClean());
        searchEntryPoint_ = null;
      }
      return searchEntryPointBuilder_;
    }
<pre>
Optional. Google search entry for the following-up web searches.
</pre>

<code>
optional .google.cloud.vertexai.v1.SearchEntryPoint search_entry_point = 4 [(.google.api.field_behavior) = OPTIONAL];
</code>
java-vertexai/proto-google-cloud-vertexai-v1/src/main/java/com/google/cloud/vertexai/api/GroundingMetadata.java