@Immutable
@ElementTypesAreNonnullByDefault
public final class ImmutableIntArray implements Serializable {
  private static final ImmutableIntArray EMPTY = new ImmutableIntArray(new int[0]);

  /** Returns the empty array. */
  public static ImmutableIntArray of() {
    return EMPTY;
  }

  /** Returns an immutable array containing a single value. */
  public static ImmutableIntArray of(int e0) {
    return new ImmutableIntArray(new int[] {e0});

    ImmutableIntArray iia0 = ImmutableIntArray.of();
    ImmutableIntArray iia1 = ImmutableIntArray.of(5);
    ImmutableIntArray iia3 = ImmutableIntArray.of(5, 25, 125);

    assertThat(iia0.subArray(0, 0)).isSameInstanceAs(ImmutableIntArray.of());
    assertThat(iia1.subArray(0, 0)).isSameInstanceAs(ImmutableIntArray.of());
    assertThat(iia1.subArray(1, 1)).isSameInstanceAs(ImmutableIntArray.of());

    assertThat(ImmutableIntArray.of(0, 1, 3).stream().toArray()).isEqualTo(new int[] {0, 1, 3});
  }

  public void testSubArray() {
    ImmutableIntArray iia0 = ImmutableIntArray.of();
    ImmutableIntArray iia1 = ImmutableIntArray.of(5);
    ImmutableIntArray iia3 = ImmutableIntArray.of(5, 25, 125);

    assertThat(iia0.subArray(0, 0)).isSameInstanceAs(ImmutableIntArray.of());

 * href="https://github.com/google/guava/wiki/PrimitivesExplained">primitive utilities</a>.
 *
 * <h2>Contents</h2>
 *
 * <h3>Value types</h3>
 *
 * <ul>
 *   <li>{@link ImmutableDoubleArray}
 *   <li>{@link ImmutableIntArray}
 *   <li>{@link ImmutableLongrray}
 *   <li>{@link UnsignedInteger}
 *   <li>{@link UnsignedLong}
 * </ul>
 *
 * <h3>Per-type static utilities</h3>
 *
 * <ul>
 *   <li>{@link Booleans}

   * the returned list is unspecified.
   *
   * <p>The returned list is serializable.
   *
   * <p><b>Note:</b> when possible, you should represent your data as an {@link ImmutableIntArray}
   * instead, which has an {@link ImmutableIntArray#asList asList} view.
   *
   * @param backingArray the array to back the list
   * @return a list view of the array
   */
  public static List<Integer> asList(int... backingArray) {