h[1] = h[2] = h[3] = 0;
        return h;
    }

    /**
     * Concatenates multiple byte arrays into a single array.
     */
    private static byte[] concat(byte[]... arrays) {
        int total = 0;
        for (byte[] a : arrays) {
            total += a.length;
        }
        byte[] res = new byte[total];
        int off = 0;
        for (byte[] a : arrays) {

    String expected = "abcde";

    assertEquals(expected, CharSource.concat(ImmutableList.of(c1, c2, c3)).read());
    assertEquals(expected, CharSource.concat(c1, c2, c3).read());
    assertEquals(expected, CharSource.concat(ImmutableList.of(c1, c2, c3).iterator()).read());
    assertFalse(CharSource.concat(c1, c2, c3).isEmpty());

    CharSource emptyConcat = CharSource.concat(CharSource.empty(), CharSource.empty());

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

  private static Double[] concat(Double[] left, Double[] right) {
    Double[] result = new Double[left.length + right.length];
    System.arraycopy(left, 0, result, 0, left.length);

      Float[] prefix = {Float.MIN_VALUE, Float.MAX_VALUE};
      Float[] suffix = {86.0f, 99.0f};
      Float[] all = concat(concat(prefix, elements), suffix);
      return asList(all).subList(2, elements.length + 2);
    }
  }

  private static Float[] concat(Float[] left, Float[] right) {
    Float[] result = new Float[left.length + right.length];
    System.arraycopy(left, 0, result, 0, left.length);

      Float[] prefix = {Float.MIN_VALUE, Float.MAX_VALUE};
      Float[] suffix = {86.0f, 99.0f};
      Float[] all = concat(concat(prefix, elements), suffix);
      return asList(all).subList(2, elements.length + 2);
    }
  }

  private static Float[] concat(Float[] left, Float[] right) {
    Float[] result = new Float[left.length + right.length];
    System.arraycopy(left, 0, result, 0, left.length);

      Integer[] prefix = {Integer.MIN_VALUE, Integer.MAX_VALUE};
      Integer[] suffix = {(int) 86, (int) 99};
      Integer[] all = concat(concat(prefix, elements), suffix);
      return asList(all).subList(2, elements.length + 2);
    }
  }

  private static Integer[] concat(Integer[] left, Integer[] right) {
    Integer[] result = new Integer[left.length + right.length];
    System.arraycopy(left, 0, result, 0, left.length);

      sources.add(newByteSource(start, span));
      start += span;
    }
    ByteSource joined = ByteSource.concat(sources);
    assertTrue(newByteSource(0, start).contentEquals(joined));
  }

  public void testReadSingleByte() throws Exception {
    ByteSource source = newByteSource(0, 10);
    ByteSource joined = ByteSource.concat(source, source);
    assertEquals(20, joined.size());
    InputStream in = joined.openStream();

   * iterator supports it.
   *
   * <p><b>{@code Stream} equivalent:</b> use nested calls to {@link Stream#concat}, or see the
   * advice in {@link #concat(Iterable...)}.
   *
   * @since 20.0
   */
  public static <T extends @Nullable Object> FluentIterable<T> concat(
      Iterable<? extends T> a, Iterable<? extends T> b, Iterable<? extends T> c) {
    return concatNoDefensiveCopy(a, b, c);
  }

   * iterator supports it.
   *
   * <p><b>{@code Stream} equivalent:</b> use nested calls to {@link Stream#concat}, or see the
   * advice in {@link #concat(Iterable...)}.
   *
   * @since 20.0
   */
  public static <T extends @Nullable Object> FluentIterable<T> concat(
      Iterable<? extends T> a, Iterable<? extends T> b, Iterable<? extends T> c) {
    return concatNoDefensiveCopy(a, b, c);
  }

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