return putAll(key, asList(values));
    }

    /**
     * Stores another multimap's entries in the built multimap. The generated multimap's key and
     * value orderings correspond to the iteration ordering of the {@code multimap.asMap()} view,
     * with new keys and values following any existing keys and values.
     *

        mapEntries = Ordering.from(keyComparator).<K>onKeys().immutableSortedCopy(mapEntries);
      }
      return fromMapBuilderEntries(mapEntries, valueComparator);
    }
  }

  /**
   * Returns an immutable set multimap containing the same mappings as {@code multimap}. The
   * generated multimap's key and value orderings correspond to the iteration ordering of the {@code

        mapEntries = Ordering.from(keyComparator).<K>onKeys().immutableSortedCopy(mapEntries);
      }
      return fromMapBuilderEntries(mapEntries, valueComparator);
    }
  }

  /**
   * Returns an immutable set multimap containing the same mappings as {@code multimap}. The
   * generated multimap's key and value orderings correspond to the iteration ordering of the {@code

      return putAll(key, asList(values));
    }

    /**
     * Stores another multimap's entries in the built multimap. The generated multimap's key and
     * value orderings correspond to the iteration ordering of the {@code multimap.asMap()} view,
     * with new keys and values following any existing keys and values.
     *

    testComparator(arbitrary, list);
  }

  public void testUsingToString() {
    Ordering<Object> ordering = Ordering.usingToString();
    testComparator(ordering, 1, 12, 124, 2);
    assertThat(ordering.toString()).isEqualTo("Ordering.usingToString()");
    assertThat(reserialize(ordering)).isSameInstanceAs(ordering);
  }

  // use an enum to get easy serializability

    testComparator(arbitrary, list);
  }

  public void testUsingToString() {
    Ordering<Object> ordering = Ordering.usingToString();
    testComparator(ordering, 1, 12, 124, 2);
    assertThat(ordering.toString()).isEqualTo("Ordering.usingToString()");
    assertThat(reserialize(ordering)).isSameInstanceAs(ordering);
  }

  // use an enum to get easy serializability

import org.jspecify.annotations.Nullable;

/** An ordering that treats {@code null} as less than all other values. */
@GwtCompatible
final class NullsFirstOrdering<T extends @Nullable Object> extends Ordering<@Nullable T>
    implements Serializable {
  final Ordering<? super T> ordering;

  NullsFirstOrdering(Ordering<? super T> ordering) {
    this.ordering = ordering;
  }

  @Override

import org.jspecify.annotations.Nullable;

/** An ordering that treats {@code null} as greater than all other values. */
@GwtCompatible
final class NullsLastOrdering<T extends @Nullable Object> extends Ordering<@Nullable T>
    implements Serializable {
  final Ordering<? super T> ordering;

  NullsLastOrdering(Ordering<? super T> ordering) {
    this.ordering = ordering;
  }

  @Override

import org.jspecify.annotations.Nullable;

/** An ordering that treats {@code null} as greater than all other values. */
@GwtCompatible
final class NullsLastOrdering<T extends @Nullable Object> extends Ordering<@Nullable T>
    implements Serializable {
  final Ordering<? super T> ordering;

  NullsLastOrdering(Ordering<? super T> ordering) {
    this.ordering = ordering;
  }

  @Override

    Ordering<@Nullable Comparable<?>> result = nullsLast;
    if (result == null) {
      result = nullsLast = super.<Comparable<?>>nullsLast();
    }
    return (Ordering<@Nullable S>) result;
  }

  @Override
  @SuppressWarnings("unchecked") // TODO(kevinb): the right way to explain this??
  public <S extends Comparable<?>> Ordering<S> reverse() {