if (key == null) {
      int unused = keyComparator().compare(key, key);
    }
    return super.createCollection(key);
  }

  /**
   * Returns the comparator that orders the multimap keys.
   *
   * @deprecated Use {@code ((NavigableSet<K>) multimap.keySet()).comparator()} instead.
   */
  @Deprecated
  public Comparator<? super K> keyComparator() {
    return keyComparator;

import com.google.common.annotations.GwtCompatible;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A {@code Multiset} implementation with predictable iteration order. Its iterator orders elements
 * according to when the first occurrence of the element was added. When the multiset contains
 * multiple instances of an element, those instances are consecutive in the iteration order. If all