Thank you Brian, I’m sorry I missed this point! The hint in this case is the
parameter on the overloaded constructor; if set high enough, the
initially-allocated buffer will guarantee exactly one array allocation with no
growth. This is identical to the ByteArrayOutputStream behavior described on
[1].
However, both issues focus on the far more common case of not knowing the
final payload size, or perhaps making a bad guess; [1] attempts to modify the
scale while [2] rewrites the data structure for greater gain.
John
From: core-libs-dev <[email protected]> On Behalf Of Brian
Burkhalter
Sent: Friday, April 4, 2025 3:31 PM
To: [email protected]
Subject: RE: [EXTERNAL] JDK-8352891 Performance improvements to
ByteArrayOutputStream
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I did not notice that Alan’s comment below, about adding a hint as to the
maximum expected size, has been specifically addressed anywhere in this
discussion. It might not be all that pertinent to the main thread of
discussion, however, but it would certainly be useful for the issue [1], which
I linked to [2].
Brian
[1] https://bugs.openjdk.org/browse/JDK-8329287
[2] https://bugs.openjdk.org/browse/JDK-8353729
On Apr 2, 2025, at 3:52 AM, Alan Bateman
<[email protected]<mailto:[email protected]>> wrote:
[…] and whether having a parameter to specify the initial size or some hint of
the max size would help the discussion.
