On Tue, 5 Sep 2023 23:43:31 GMT, Glavo <[email protected]> wrote:
>> I mainly made these optimizations:
>>
>> * Avoid allocating `StringBuilder` when there are no characters in the URL
>> that need to be encoded;
>> * Implement a fast path for UTF-8.
>>
>> In addition to improving performance, these optimizations also reduce
>> temporary objects:
>>
>> * It no longer allocates any object when there are no characters in the URL
>> that need to be encoded;
>> * The initial size of StringBuilder is larger to avoid expansion as much as
>> possible;
>> * For UTF-8, the temporary `CharArrayWriter`, strings and byte arrays are no
>> longer needed.
>>
>> The results of the `URLEncodeDecode` benchmark:
>>
>>
>> Before:
>> Benchmark (count) (maxLength) (mySeed) Mode Cnt
>> Score Error Units
>> URLEncodeDecode.testEncodeUTF8 1024 1024 3 avgt 15
>> 5.587 ? 0.010 ms/op
>>
>> After:
>> Benchmark (count) (maxLength) (mySeed) Mode Cnt
>> Score Error Units
>> URLEncodeDecode.testEncodeUTF8 1024 1024 3 avgt 15
>> 3.582 ? 0.054 ms/op
>>
>>
>> I also updated the tests to add more test cases.
>
> Glavo has updated the pull request incrementally with one additional commit
> since the last revision:
>
> Remove unused import
src/java.base/share/classes/java/net/URLEncoder.java line 140:
> 138: }
> 139:
> 140: private static void encodeByte(StringBuilder out, byte b) {
This routine is basically
out.append('%');
HexFormat.of().withUpperCase().toHexDigits(out, b);
If this doesn't perform as well (with or without
`HexFormat.of().withUpperCase()` cached in a static field) then that might be
worth looking into.
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/15354#discussion_r1317213624
