* load data through their streams). Prefer using the {@link #concat(Iterable)} overload if
   * possible.
   *
   * @param sources the sources to concatenate
   * @return a {@code CharSource} containing the concatenated data
   * @throws NullPointerException if any of {@code sources} is {@code null}
   * @since 15.0
   */
  public static CharSource concat(Iterator<? extends CharSource> sources) {

   * load data through their streams). Prefer using the {@link #concat(Iterable)} overload if
   * possible.
   *
   * @param sources the sources to concatenate
   * @return a {@code CharSource} containing the concatenated data
   * @throws NullPointerException if any of {@code sources} is {@code null}
   * @since 15.0
   */
  public static CharSource concat(Iterator<? extends CharSource> sources) {

    assertThat(Ints.concat()).isEqualTo(EMPTY);
    assertThat(Ints.concat(EMPTY)).isEqualTo(EMPTY);
    assertThat(Ints.concat(EMPTY, EMPTY, EMPTY)).isEqualTo(EMPTY);
    assertThat(Ints.concat(ARRAY1)).isEqualTo(ARRAY1);
    assertThat(Ints.concat(ARRAY1)).isNotSameInstanceAs(ARRAY1);
    assertThat(Ints.concat(EMPTY, ARRAY1, EMPTY)).isEqualTo(ARRAY1);
    assertThat(Ints.concat(ARRAY1, ARRAY1, ARRAY1))

              "io",
              "math",
              "net",
              "primitives",
              "reflect",
              "util.concurrent",
              "xml")
          .transform("com.google.common."::concat)
          .toSet();

  public void testClassesHaveOverrides() throws Exception {
    for (ClassInfo info : ClassPath.from(getClass().getClassLoader()).getAllClasses()) {

      Integer[] suffix = {86, 99};
      Integer[] all = concat(concat(prefix, elements), suffix);
      return makeArray(all).subArray(2, elements.length + 2).asList();
    }
  }

  @J2ktIncompatible
  @GwtIncompatible // used only from suite
  private static Integer[] concat(Integer[] a, Integer[] b) {
    return ObjectArrays.concat(a, b, Integer.class);
  }

  @J2ktIncompatible

      Double[] suffix = {86.0, 99.0};
      Double[] all = concat(concat(prefix, elements), suffix);
      return makeArray(all).subArray(2, elements.length + 2).asList();
    }
  }

  @J2ktIncompatible
  @GwtIncompatible // used only from suite
  @AndroidIncompatible
  private static Double[] concat(Double[] a, Double[] b) {
    return ObjectArrays.concat(a, b, Double.class);
  }

  @J2ktIncompatible

                    .stream()
                    .filter(e -> isAttribute(e.getKey()))
                    .map(e -> new Pair<>(e.getKey(), (String) e.getValue()))
                    .collect(Collectors.toMap(Pair::getFirst, Pair::getSecond)));
            return result;
        } catch (InstantiationException | IllegalAccessException e) {
            final String msg = "Cannot create a new instance: " + entityType.getName();

    List<Integer> list2 = newArrayList(4);

    assertThrows(NullPointerException.class, () -> Iterables.concat(list1, null, list2));
  }

  public void testConcatPeformingFiniteCycle() {
    Iterable<Integer> iterable = asList(1, 2, 3);
    int n = 4;
    Iterable<Integer> repeated = Iterables.concat(nCopies(n, iterable));
    assertThat(repeated).containsExactly(1, 2, 3, 1, 2, 3, 1, 2, 3, 1, 2, 3).inOrder();
  }

   * load data through their streams). Prefer using the {@link #concat(Iterable)} overload if
   * possible.
   *
   * @param sources the sources to concatenate
   * @return a {@code ByteSource} containing the concatenated data
   * @throws NullPointerException if any of {@code sources} is {@code null}
   * @since 15.0
   */
  public static ByteSource concat(Iterator<? extends ByteSource> sources) {

   * @param second the second array of elements to concatenate
   * @param type the component type of the returned array
   */
  @GwtIncompatible // Array.newInstance(Class, int)
  public static <T extends @Nullable Object> T[] concat(
      T[] first, T[] second, Class<@NonNull T> type) {
    T[] result = newArray(type, first.length + second.length);
    arraycopy(first, 0, result, 0, first.length);