RFR: 8333833: UUID toString removes the use of ByteArrayLittleEndian [v3]

[Chen Liang]

On Sat, 8 Jun 2024 23:30:38 GMT, Shaojin Wen <duke at openjdk.org> wrote:

>> After PR #16245, C2 optimizes stores into primitive arrays by combining values ​​into larger stores. In the UUID.toString method, ByteArrayLittleEndian can be removed, making the code more elegant and faster.
>
> Shaojin Wen has updated the pull request incrementally with one additional commit since the last revision:
> 
>   change method name, putHex -> putHex4, and fix comments

src/java.base/share/classes/java/util/UUID.java line 1:

> 1: /*

We can update copyright year to 2024

src/java.base/share/classes/jdk/internal/util/HexDigits.java line 1:

> 1: /*

We can update copyright header to `Copyright (c) 2023, 2024, Oracle ...`

src/java.base/share/classes/jdk/internal/util/HexDigits.java line 118:

> 116:     /**
> 117:      * Insert the unsigned 2-byte integer into the buffer as 4 hexadecimal digit ASCII bytes,
> 118:      * {@code i} only least significant 16 bits are used.

Suggestion:

     * only least significant 16 bits of {@code i} are used.

src/java.base/share/classes/jdk/internal/util/HexDigits.java line 123:

> 121:      * @param i to convert
> 122:      */
> 123:     public static void putHex4(byte[] buffer, int off, int i) {

I recommend the name `put4`. `Hex` is redundant within the context of `HexDigits`.

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PR Review Comment: https://git.openjdk.org/jdk/pull/19610#discussion_r1632187884
PR Review Comment: https://git.openjdk.org/jdk/pull/19610#discussion_r1632187984
PR Review Comment: https://git.openjdk.org/jdk/pull/19610#discussion_r1632187743
PR Review Comment: https://git.openjdk.org/jdk/pull/19610#discussion_r1632187666