On Mon, 18 Sep 2023 13:40:48 GMT, Chen Liang <li...@openjdk.org> wrote:
>> In the improvement of @cl4es PR #15591, the advantages of non-lookup-table
>> were discussed.
>>
>> But if the input is byte[], using lookup table can improve performance.
>>
>> For HexFormat#formatHex(Appendable, byte[]) and HexFormat#formatHex(byte[]),
>> If the length of byte[] is larger, the performance of table lookup will be
>> improved more obviously.
>
> src/java.base/share/classes/java/util/HexFormat.java line 422:
>
>> 420: toHexDigits(out, bytes[fromIndex + i]);
>> 421: }
>> 422: out.append(suffix);
>
> Maybe change this whole `else` block to
>
> for (int i = 0; i < length; i++) {
> if (i > 0)
> out.append(delimiter);
> out.append(prefix);
> toHexDigits(out, bytes[fromIndex + i]);
> out.append(suffix);
> }
>
> for clarity?
The original (and current) is coded to avoid a condition inside the loop.
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/15768#discussion_r1329167394
