private void advance() throws IOException {
    close();
    if (it.hasNext()) {
      current = it.next().openStream();
    }
  }

  @Override
  public int read(char[] cbuf, int off, int len) throws IOException {
    checkNotNull(cbuf);
    if (current == null) {
      return -1;
    }
    int result = current.read(cbuf, off, len);
    if (result == -1) {
      advance();

    StringBuilder result = new StringBuilder();

    @Override
    public Appendable append(CharSequence csq) {
      result.append(csq);
      return this;
    }

    @Override
    public Appendable append(char c) {
      result.append(c);
      return this;
    }

    @Override
    public Appendable append(CharSequence csq, int start, int end) {
      result.append(csq, start, end);
      return this;
    }

    hasher.putLong(0x0807060504030201L);
    hasher.assertBytes(new byte[] {1, 2, 3, 4, 5, 6, 7, 8});
  }

  public void testChar() {
    TestHasher hasher = new TestHasher();
    hasher.putChar((char) 0x0201);
    hasher.assertBytes(new byte[] {1, 2});
  }

  public void testString() {
    Random random = new Random();
    for (int i = 0; i < 100; i++) {
      byte[] bytes = new byte[64];

    checkOpen();
    requireNonNull(seq); // safe because of checkOpen
    return hasRemaining() ? seq.charAt(pos++) : -1;
  }

  @Override
  public synchronized int read(char[] cbuf, int off, int len) throws IOException {
    checkPositionIndexes(off, off + len, cbuf.length);
    checkOpen();
    requireNonNull(seq); // safe because of checkOpen
    if (!hasRemaining()) {
      return -1;

  @CanIgnoreReturnValue
  public final Hasher putShort(short s) {
    buffer.putShort(s);
    munchIfFull();
    return this;
  }

  @Override
  @CanIgnoreReturnValue
  public final Hasher putChar(char c) {
    buffer.putChar(c);
    munchIfFull();
    return this;
  }

  @Override
  @CanIgnoreReturnValue
  public final Hasher putInt(int i) {
    buffer.putInt(i);
    munchIfFull();

    HashCode unused = sink.hash();
    sink.assertInvariants(8);
    sink.assertBytes(new byte[] {1, 2, 3, 4, 5, 6, 7, 8});
  }

  public void testChar() {
    Sink sink = new Sink(4);
    sink.putChar((char) 0x0201);
    HashCode unused = sink.hash();
    sink.assertInvariants(2);
    sink.assertBytes(new byte[] {1, 2, 0, 0}); // padded with zeros
  }

  public void testString() {
    Random random = new Random();

      return insertionOrder;
    }
  }

  public static class SampleChars extends SampleElements<Character> {
    public SampleChars() {
      super((char) 0, (char) 1, (char) 2, (char) 3, (char) 4);
    }
  }

      return insertionOrder;
    }
  }

  public static class SampleChars extends SampleElements<Character> {
    public SampleChars() {
      super((char) 0, (char) 1, (char) 2, (char) 3, (char) 4);
    }
  }

          private final char[] unknown = new char[] {'?'};

          @Override
          protected char[] escapeUnsafe(int c) {
            return unknown;
          }
        };
    EscaperAsserts.assertBasic(replacingEscaper);

    // Replacements are applied first regardless of whether the character is in
    // the safe range or not ('&' is a safe char while '\t' and '\n' are not).
    assertEquals(

   * the given character set. Malformed input and unmappable characters will be replaced.
   *
   * @param reader input source
   * @param charset character set used for encoding chars to bytes
   * @param bufferSize size of internal input and output buffers
   * @throws IllegalArgumentException if bufferSize is non-positive
   */
  ReaderInputStream(Reader reader, Charset charset, int bufferSize) {