Java8Compatibility.flip(buf2);
    assertEquals(expected, buf2.toString());
    assertFullyRead(reader);

    // read in chunks to fixed CharBuffer
    reader = new CharSequenceReader(charSequence);
    buf2 = CharBuffer.allocate(5);
    builder = new StringBuilder();
    while (reader.read(buf2) != -1) {
      Java8Compatibility.flip(buf2);
      builder.append(buf2);

    Java8Compatibility.flip(buf2);
    assertEquals(expected, buf2.toString());
    assertFullyRead(reader);

    // read in chunks to fixed CharBuffer
    reader = new CharSequenceReader(charSequence);
    buf2 = CharBuffer.allocate(5);
    builder = new StringBuilder();
    while (reader.read(buf2) != -1) {
      Java8Compatibility.flip(buf2);
      builder.append(buf2);

    }

    ByteBuffer buf = ByteBuffer.wrap(createBuffer());
    long total = 0;
    while (from.read(buf) != -1) {
      Java8Compatibility.flip(buf);
      while (buf.hasRemaining()) {
        total += to.write(buf);
      }
      Java8Compatibility.clear(buf);
    }
    return total;
  }

  /** Max array length on JVM. */
  private static final int MAX_ARRAY_LEN = Integer.MAX_VALUE - 8;