val b0: Int
    val timeoutBefore = source.timeout().timeoutNanos()
    source.timeout().clearTimeout()
    try {
      b0 = source.readByte() and 0xff
    } finally {
      source.timeout().timeout(timeoutBefore, TimeUnit.NANOSECONDS)
    }

    opcode = b0 and B0_MASK_OPCODE
    isFinalFrame = b0 and B0_FLAG_FIN != 0
    isControlFrame = b0 and OPCODE_FLAG_CONTROL != 0

}

func (sr *sparseFileReader) Read(b []byte) (n int, err error) {
	finished := int64(len(b)) >= sr.logicalRemaining()
	if finished {
		b = b[:sr.logicalRemaining()]
	}

	b0 := b
	endPos := sr.pos + int64(len(b))
	for endPos > sr.pos && err == nil {
		var nf int // Bytes read in fragment
		holeStart, holeEnd := sr.sp[0].Offset, sr.sp[0].endOffset()

								b2 = b3
							}
						}
						toPrint = append(toPrint, fmt.Sprintf("\t%s: %s", string(b), string(b2)))
					}
				}
			} else {
				b0 := ""
				if ndjson {
					b, _ := json.Marshal(file)
					b0 = fmt.Sprintf("%s: ", string(b))
				}
				b, err := decode(r, file)
				if err != nil {
					return err
				}
				b = bytes.TrimSpace(b)
				if !ndjson {

   * products that you would get from nesting for loops:
   *
   * <pre>{@code
   * for (B b0 : lists.get(0)) {
   *   for (B b1 : lists.get(1)) {
   *     ...
   *     ImmutableList<B> tuple = ImmutableList.of(b0, b1, ...);
   *     // operate on tuple
   *   }
   * }
   * }</pre>
   *

}

func (sw *sparseFileWriter) Write(b []byte) (n int, err error) {
	overwrite := int64(len(b)) > sw.logicalRemaining()
	if overwrite {
		b = b[:sw.logicalRemaining()]
	}

	b0 := b
	endPos := sw.pos + int64(len(b))
	for endPos > sw.pos && err == nil {
		var nf int // Bytes written in fragment
		dataStart, dataEnd := sw.sp[0].Offset, sw.sp[0].endOffset()