private com.google.protobuf.SingleFieldBuilderV3<
            com.google.cloud.vertexai.api.ReservationAffinity,
            com.google.cloud.vertexai.api.ReservationAffinity.Builder,
            com.google.cloud.vertexai.api.ReservationAffinityOrBuilder>
        getReservationAffinityFieldBuilder() {
      if (reservationAffinityBuilder_ == null) {
        reservationAffinityBuilder_ =
            new com.google.protobuf.SingleFieldBuilderV3<
                com.google.cloud.vertexai.api.ReservationAffinity,
                com.google.cloud.vertexai.api.ReservationAffinity.Builder,
                com.google.cloud.vertexai.api.ReservationAffinityOrBuilder>(
                getReservationAffinity(), getParentForChildren(), isClean());
        reservationAffinity_ = null;
      }
      return reservationAffinityBuilder_;
    }
<pre>
Optional. Immutable. Configuration controlling how this resource pool
consumes reservation.
</pre>

<code>
.google.cloud.vertexai.v1.ReservationAffinity reservation_affinity = 5 [(.google.api.field_behavior) = IMMUTABLE, (.google.api.field_behavior) = OPTIONAL];
</code>
java-vertexai/proto-google-cloud-vertexai-v1/src/main/java/com/google/cloud/vertexai/api/MachineSpec.java