*
   * <p>Because the values for a given key may have duplicates and follow the insertion ordering,
   * this method returns a {@link List}, instead of the {@link java.util.Collection} specified in
   * the {@link Multimap} interface.
   */
  @Override
  List<V> get(@ParametricNullness K key);

  /**
   * {@inheritDoc}
   *
   * <p>Because the values for a given key may have duplicates and follow the insertion ordering,

   *
   * <p>Because the values for a given key may have duplicates and follow the insertion ordering,
   * this method returns a {@link List}, instead of the {@link java.util.Collection} specified in
   * the {@link Multimap} interface.
   */
  @Override
  List<V> get(@ParametricNullness K key);

  /**
   * {@inheritDoc}
   *
   * <p>Because the values for a given key may have duplicates and follow the insertion ordering,

Guillaume Nodet <******@****.***> 1729859506 +0200

      }
    }

    /**
     * Scans the first {@code size} elements of {@code entries} looking for duplicate keys. If
     * duplicates are found, a new correctly-sized array is returned with the same elements (up to
     * {@code size}), except containing only the last occurrence of each duplicate key. Otherwise
     * {@code null} is returned.
     */
    private static <K, V> Entry<K, V> @Nullable [] lastEntryForEachKey(

        urls.add("http://example.com/page1"); // Duplicate
        urls.add("http://example.com/page3");
        urls.add("http://example.com/page2"); // Duplicate

        Set<RequestData> result = crawlerThread.getAnchorSet(urls);
        assertNotNull(result, "getAnchorSet should handle duplicates");

        // Since it returns a Set, duplicates should be handled by URL comparison

    @SuppressWarnings("unchecked")
    E[] array = (E[]) elements.toArray();
    /*
     * For a Set, we guess that it contains no duplicates. That's just a guess for purpose of
     * sizing; if the Set uses different equality semantics, it might contain duplicates according
     * to equals(), and we will deduplicate those properly, albeit at some cost in allocations.
     */
    int expectedSize =

    }

    @Override
    public Set<E> create(Object... elements) {
      Object[] duplicated = new Object[elements.length * 2];
      for (int i = 0; i < elements.length; i++) {
        duplicated[i] = elements[i];
        duplicated[i + elements.length] = elements[i];
      }
      return ((Multiset<E>) gen.create(duplicated)).elementSet();
    }

    @Override
    public E[] createArray(int length) {

    }

    @Override
    public Set<E> create(Object... elements) {
      Object[] duplicated = new Object[elements.length * 2];
      for (int i = 0; i < elements.length; i++) {
        duplicated[i] = elements[i];
        duplicated[i + elements.length] = elements[i];
      }
      return ((Multiset<E>) gen.create(duplicated)).elementSet();
    }

    @Override
    public E[] createArray(int length) {

Guillaume Nodet <******@****.***> 1729859506 +0200

    @Nullable Object[] alternatingKeysAndValues;
    int size;
    boolean entriesUsed;

    /**
     * If non-null, a duplicate key we found in a previous buildKeepingLast() or buildOrThrow()
     * call. A later buildOrThrow() can simply report this duplicate immediately.
     */
    @Nullable DuplicateKey duplicateKey;

    /**