return treeKeys(Ordering.natural());
  }

  /**
   * Uses a {@link TreeMap} sorted by the specified comparator to map keys to value collections.
   *
   * <p>The collections returned by {@link Multimap#keySet()}, {@link Multimap#keys()}, and {@link
   * Multimap#asMap()} will iterate through the keys in sorted order.
   *
   * <p>For all multimaps generated by the resulting builder, the {@link Multimap#keySet()} can be

@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
public final class TreeMultiset<E extends @Nullable Object> extends AbstractSortedMultiset<E>
    implements Serializable {

  /**
   * Creates a new, empty multiset, sorted according to the elements' natural order. All elements
   * inserted into the multiset must implement the {@code Comparable} interface. Furthermore, all

import com.google.common.annotations.J2ktIncompatible;
import com.google.errorprone.annotations.DoNotCall;
import java.util.Collections;
import java.util.NoSuchElementException;
import java.util.Set;

/**
 * A sorted set of contiguous values in a given {@link DiscreteDomain}. Example:
 *
 * <pre>{@code
 * ContiguousSet.create(Range.closed(5, 42), DiscreteDomain.integers())
 * }</pre>
 *

     * order in which entries were inserted into the builder, unless {@link #orderEntriesByValue}
     * was called, in which case entries are sorted by value.
     *
     * <p>Prefer the equivalent method {@link #buildOrThrow()} to make it explicit that the method
     * will throw an exception if there are duplicate keys or values. The {@code build()} method

@ElementTypesAreNonnullByDefault
public final class Comparators {
  private Comparators() {}

  /**
   * Returns a new comparator which sorts iterables by comparing corresponding elements pairwise
   * until a nonzero result is found; imposes "dictionary order." If the end of one iterable is
   * reached, but not the other, the shorter iterable is considered to be less than the longer one.

    tree.put(1.0, 2.0);
    tree.put(2.0, 3.0);
    tree.put(3.0, 4.0);
    tree.put(4.0, 5.0);

    SortedSetMultimap<Double, Double> sorted = Multimaps.unmodifiableSortedSetMultimap(tree);
    TreeMultimap<Double, Double> copyFromSorted = TreeMultimap.create(sorted);
    assertEquals(tree, copyFromSorted);
    assertSame(Ordering.natural(), copyFromSorted.keyComparator());

    if (k == 0 || !iterator.hasNext()) {
      return Collections.emptyList();
    } else if (k >= Integer.MAX_VALUE / 2) {
      // k is really large; just do a straightforward sorted-copy-and-sublist
      ArrayList<E> list = Lists.newArrayList(iterator);
      Collections.sort(list, this);
      if (list.size() > k) {
        list.subList(k, list.size()).clear();
      }
      list.trimToSize();

   * ImmutableList} sorted by its natural ordering, use {@code toSortedList(Ordering.natural())}.
   *
   * <p><b>{@code Stream} equivalent:</b> pass {@link ImmutableList#toImmutableList} to {@code
   * stream.sorted(comparator).collect()}.
   *
   * @param comparator the function by which to sort list elements

   * ImmutableList} sorted by its natural ordering, use {@code toSortedList(Ordering.natural())}.
   *
   * <p><b>{@code Stream} equivalent:</b> {@code
   * ImmutableList.copyOf(stream.sorted(comparator).iterator())}, or pass {@link
   * ImmutableList#toImmutableList} to {@code stream.sorted(comparator).collect()}.
   *
   * @param comparator the function by which to sort list elements

                    .map(Object::toString)
                    .filter(s -> s.startsWith("SourceCacheKey"))
                    .map(s -> s.substring("SourceCacheKey[location=".length(), s.indexOf(", tag")))
                    .sorted()
                    .distinct()
                    .toList();
            logger.debug("ModelCache contains " + paths.size());
            paths.forEach(s -> logger.debug("    " + s));
        }