RFR: 8305811: (bf) Improve performance of CharBuffer::append(CharSequence[,int,int]) [v5]

[Brian Burkhalter]

On Fri, 14 Apr 2023 06:53:34 GMT, Alan Bateman <alanb at openjdk.org> wrote:

>> Brian Burkhalter has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   8305811: Use getChars() when appending a full String or StringBuffer
>
> src/java.base/share/classes/java/nio/Heap-X-Buffer.java.template line 305:
> 
>> 303:         } else if (csq instanceof StringBuffer buf) {
>> 304:             buf.getChars(start, end, hb, ix(pos));
>> 305:         }
> 
> Surprised to see legacy StringBuffer here but okay. A small suggestion is to keep check for String first, and keep the naming from the previous iteration, i.e.
> 
> 
>         if (csq instanceof String str) {
>             str.getChars(start, end, hb, ix(pos));
>         } else if (csq instanceof StringBuilder sb) {
>             sb.getChars(start, end, hb, ix(pos));
>         } else if (csq instanceof StringBuffer sb) {
>             sb.getChars(start, end, hb, ix(pos));
>         }

I put `StringBuilder` first as it is always used for the `append` without `start` and `end` and sometimes for the version without but I've no problem changing it.

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PR Review Comment: https://git.openjdk.org/jdk/pull/13415#discussion_r1166985498