/**
   * Returns a serializable ordering that uses the natural order of the values. The ordering throws
   * a {@link NullPointerException} when passed a null parameter.
   *
   * <p>The type specification is {@code <C extends Comparable>}, instead of the technically correct
   * {@code <C extends Comparable<? super C>>}, to support legacy types from before Java 5.
   *

                              - customMetric
                            properties:
                              customMetric:
                                description: Allows free-form specification of a metric.
                                minLength: 1
                                type: string
                              metric:
                                description: |-