@java.lang.Override
      public int getSerializedSize() {
        int size = memoizedSize;
        if (size != -1) return size;

        size = 0;
        if (((bitField0_ & 0x00000001) != 0)) {
          size += com.google.protobuf.CodedOutputStream.computeEnumSize(1, modelRoutingPreference_);
        }
        size += getUnknownFields().getSerializedSize();
        memoizedSize = size;
        return size;
      }
<pre>
The model routing preference.
</pre>

<code>
optional .google.cloud.vertexai.v1.GenerationConfig.RoutingConfig.AutoRoutingMode.ModelRoutingPreference model_routing_preference = 1;
</code>

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