On Thu, 23 Mar 2023 19:55:04 GMT, Alan Bateman <[email protected]> wrote:
>> src/java.base/share/classes/java/io/BufferedInputStream.java line 183:
>>
>>> 181: if (buffer == EMPTY) {
>>> 182: buf = buffer = new byte[size];
>>> 183: }
>>
>> You should probably use compareAndSet here too like in fill() - to handle
>> the case of asynchoronous close.
>> This patch makes me a bit nervous. I would advise to get feedback from @bplb
>> and @AlanBateman .
>
> Yes, I'm nervous about changing BIS too. Most of the initial revisions of the
> patch introduced compatibility issues so it had to be restricted to the no
> sub-class case. Here, it needs to CAS buf as otherwise it will break async
> close.
>
> I think the starting point for this issue is to show examples where it avoids
> needing to create the byte[] on first usage. The first use of read,
> readAllBytes, readNBytes, .. will create the byte[] but Sergey may have
> spotted some usages where it does help.
Some implementations of `getInputStream()` return `BufferedInputStream` which
is later wrapped into `BufferedInputStream` on call site, e.g.
`FileURLConnection`. With this change we can avoid allocation of byte[] in
internal BIS.
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PR Review Comment: https://git.openjdk.org/jdk/pull/13150#discussion_r1146801965
