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();
      return read(cbuf, off, len);
    }
    return result;
  }

  @Override

      Java8Compatibility.clear(cbuf);
      // The default implementation of Reader#read(CharBuffer) allocates a
      // temporary char[], so we call Reader#read(char[], int, int) instead.
      int read = (reader != null) ? reader.read(buf, 0, buf.length) : readable.read(cbuf);
      if (read == -1) {
        lineBuf.finish();
        break;
      }
      lineBuf.add(buf, 0, read);
    }
    return lines.poll();
  }

  public void write(int c) throws IOException {
    super.write(c);
    flush(); // flush write to TestOutputStream to get its behavior
  }

  @Override
  public void write(char[] cbuf, int off, int len) throws IOException {
    super.write(cbuf, off, len);
    flush();
  }

  @Override
  public void write(String str, int off, int len) throws IOException {
    super.write(str, off, len);
    flush();
  }

      @Override
      public void write(int c) throws IOException {
        super.write(c);
        flush();
      }

      @Override
      public void write(char[] cbuf, int off, int len) throws IOException {
        super.write(cbuf, off, len);
        flush();
      }

      @Override
      public void write(String str, int off, int len) throws IOException {
        super.write(str, off, len);
        flush();

      if (finishLine(cbuf[pos] == '\n')) {
        pos++;
      }
    }

    int start = pos;
    for (int end = off + len; pos < end; pos++) {
      switch (cbuf[pos]) {
        case '\r':
          line.append(cbuf, start, pos - start);
          sawReturn = true;
          if (pos + 1 < end) {
            if (finishLine(cbuf[pos + 1] == '\n')) {
              pos++;
            }

      if (finishLine(cbuf[pos] == '\n')) {
        pos++;
      }
    }

    int start = pos;
    for (int end = off + len; pos < end; pos++) {
      switch (cbuf[pos]) {
        case '\r':
          line.append(cbuf, start, pos - start);
          sawReturn = true;
          if (pos + 1 < end) {
            if (finishLine(cbuf[pos + 1] == '\n')) {
              pos++;
            }

      @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++);
    }