if (!identifiers.containsKey(ident)) {
            identifiers.put(ident, method);
          }
        }
      }
    }
    return ImmutableList.copyOf(identifiers.values());
  }

  /** Global cache of classes to their flattened hierarchy of supertypes. */
  private static final LoadingCache<Class<?>, ImmutableSet<Class<?>>> flattenHierarchyCache =

    ImmutableMap<C, ImmutableMap<R, V>> columnMap = this.columnMap;
    return ImmutableMap.<C, Map<R, V>>copyOf(columnMap);
  }

  @Override
  public ImmutableMap<R, Map<C, V>> rowMap() {
    // Casts without copying.
    ImmutableMap<R, ImmutableMap<C, V>> rowMap = this.rowMap;
    return ImmutableMap.<R, Map<C, V>>copyOf(rowMap);
  }

  @Override
  @CheckForNull

    Arrays.fill(array, ABSENT);
    return array;
  }

  /** Equivalent to {@code Arrays.copyOf(array, newSize)}, save that the new elements are ABSENT. */
  private static int[] expandAndFillWithAbsent(int[] array, int newSize) {
    int oldSize = array.length;
    int[] result = Arrays.copyOf(array, newSize);
    Arrays.fill(result, oldSize, newSize, ABSENT);
    return result;
  }

  @Override

                new TestStringListGenerator() {

                  @Override
                  protected List<String> create(String[] elements) {
                    return new StandardImplForwardingList<>(ImmutableList.copyOf(elements));
                  }
                })
            .named("ForwardingList[ImmutableList] with standard implementations")
            .withFeatures(CollectionSize.ANY, CollectionFeature.ALLOWS_NULL_QUERIES)

                new TestStringListGenerator() {

                  @Override
                  protected List<String> create(String[] elements) {
                    return new StandardImplForwardingList<>(ImmutableList.copyOf(elements));
                  }
                })
            .named("ForwardingList[ImmutableList] with standard implementations")
            .withFeatures(CollectionSize.ANY, CollectionFeature.ALLOWS_NULL_QUERIES)

   */
  public static <K, V> ImmutableMap<K, V> copyOf(Map<? extends K, ? extends V> map) {
    if ((map instanceof ImmutableMap) && !(map instanceof SortedMap)) {
      @SuppressWarnings("unchecked") // safe since map is not writable
      ImmutableMap<K, V> kvMap = (ImmutableMap<K, V>) map;
      if (!kvMap.isPartialView()) {
        return kvMap;
      }
    }
    return copyOf(map.entrySet());
  }

  /**

   * undocumented and subject to change.
   *
   * @throws NullPointerException if any key or value in {@code multimap} is null
   */
  public static <K, V> ImmutableListMultimap<K, V> copyOf(
      Multimap<? extends K, ? extends V> multimap) {
    if (multimap.isEmpty()) {
      return of();
    }

    // TODO(lowasser): copy ImmutableSetMultimap by using asList() on the sets

    for (int i = 0; i < 3; i++) {
      assertEquals(i + 1, list.get(i).intValue());
    }
    assertEquals(ImmutableList.of(1, 2, 3), ImmutableList.copyOf(list.iterator()));
    assertEquals(ImmutableList.of(1, 2, 3), ImmutableList.copyOf(list.toArray(new Integer[0])));
  }

  @J2ktIncompatible
  @GwtIncompatible // suite
  public static class BuiltTests extends TestCase {
    public static Test suite() {

   * <p><b>Note:</b> essentially the only reason to use this method is when you will need to add or
   * remove elements later. Otherwise, for non-null elements use {@link ImmutableList#of()} (for
   * varargs) or {@link ImmutableList#copyOf(Object[])} (for an array) instead. If any elements
   * might be null, or you need support for {@link List#set(int, Object)}, use {@link
   * Arrays#asList}.
   *

  private static void testReverse(boolean[] input, boolean[] expectedOutput) {
    input = Arrays.copyOf(input, input.length);
    Booleans.reverse(input);
    assertThat(input).isEqualTo(expectedOutput);
  }

  private static void testReverse(
      boolean[] input, int fromIndex, int toIndex, boolean[] expectedOutput) {
    input = Arrays.copyOf(input, input.length);
    Booleans.reverse(input, fromIndex, toIndex);