@Override
      public int read(CharBuffer cbuf) throws IOException {
        return reader.read(cbuf);
      }
    };
  }

  private static Reader getChunkedReader(String input, final int chunk) {
    return new FilterReader(new StringReader(input)) {
      @Override
      public int read(char[] cbuf, int off, int len) throws IOException {
        return super.read(cbuf, off, min(chunk, len));
      }
    };
  }

      @Override
      public int read(CharBuffer cbuf) throws IOException {
        return reader.read(cbuf);
      }
    };
  }

  private static Reader getChunkedReader(String input, final int chunk) {
    return new FilterReader(new StringReader(input)) {
      @Override
      public int read(char[] cbuf, int off, int len) throws IOException {
        return super.read(cbuf, off, min(chunk, len));
      }
    };
  }

  @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;
    }
    int charsToRead = min(len, remaining());
    for (int i = 0; i < charsToRead; i++) {
      cbuf[off + i] = seq.charAt(pos++);
    }

  @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;
    }
    int charsToRead = min(len, remaining());
    for (int i = 0; i < charsToRead; i++) {
      cbuf[off + i] = seq.charAt(pos++);
    }

    assertEquals(-1, empty.read());
  }

  public void testExhaust_readable() throws IOException {
    CharBuffer buf = CharBuffer.wrap(ASCII);
    assertEquals(ASCII.length(), CharStreams.exhaust(buf));
    assertEquals(0, buf.remaining());
    assertEquals(0, CharStreams.exhaust(buf));

    CharBuffer empty = CharBuffer.wrap("");
    assertEquals(0, CharStreams.exhaust(empty));

    assertEquals(-1, empty.read());
  }

  public void testExhaust_readable() throws IOException {
    CharBuffer buf = CharBuffer.wrap(ASCII);
    assertEquals(ASCII.length(), CharStreams.exhaust(buf));
    assertEquals(0, buf.remaining());
    assertEquals(0, CharStreams.exhaust(buf));

    CharBuffer empty = CharBuffer.wrap("");
    assertEquals(0, CharStreams.exhaust(empty));

        this.in = new Reader() {
            Reader delegate = null;

            @Override
            public int read(char[] cbuf, int off, int len) throws IOException {
                if (delegate == null) {
                    delegate = transform(original);
                }
                return delegate.read(cbuf, off, len);
            }

            @Override
            public void close() throws IOException {

          checkPositionIndexes(off, off + len, buf.length);

          int i = off;
          for (; i < off + len; i++) {
            int b = read();
            if (b == -1) {
              int read = i - off;
              return read == 0 ? -1 : read;
            }
            buf[i] = (byte) b;
          }
          return i - off;
        }

        @Override

func (s *scanner) cur() byte { return s.buf[s.ipos] }

// read next byte
func (s *scanner) next() byte {
	if s.pos >= atomic.LoadInt64(&s.end) {
		return nullByte
	}
	s.ipos++

	if s.ipos > s.ifill { // internal buffer is exhausted
		s.ifill = <-s.fillReady

		s.buf[0] = s.buf[len(s.buf)-1] // copy current last item to guarantee lookback
		copy(s.buf[1:], s.nbuf[:])     // copy contents of pre-filled next buffer

	// The approach here is to write 8 byte sizes if needed without
	// adding a zip64 extra in the local header (too late anyway).
	var buf []byte
	if w.isZip64() {
		buf = make([]byte, dataDescriptor64Len)
	} else {
		buf = make([]byte, dataDescriptorLen)
	}
	b := writeBuf(buf)
	b.uint32(dataDescriptorSignature) // de-facto standard, required by OS X
	b.uint32(w.CRC32)
	if w.isZip64() {
		b.uint64(w.CompressedSize64)