Hej Martin!
On 6/4/18 9:55 PM, Martin Buchholz wrote:
Hej Ivan,
IIRC I wrote the first iteration of this code.
I would expect that almost always either the buffer will be empty or
the call to available() is accurate and the read will actually read
everything in one chunk, so the byte array will be perfectly allocated
with no need for re-allocation in practice. Do you have evidence it
would be otherwise in practice?
No evidence. It is just an observation from reading code.
But suppose available() incorrectly claims that a million bytes are
available, but you only read 10. Then there's a tradeoff - the cost
of reallocation versus the risk that the mostly empty backing array
will be retained for a long time if the Process object is not garbage
collected.
On the other hand, if available() claims a million bytes, and then only
999999990 bytes were read, there will be mostly unnecessary allocation
and copying.
I'm leaning towards the status quo.
Okay, let's leave it as is :)
It was meant mostly for cleaning up the code, so if there is a doubt,
then it's better keep what we have.
With kind regards,
Ivan
On Mon, Jun 4, 2018 at 9:26 PM, Ivan Gerasimov
<ivan.gerasi...@oracle.com <mailto:ivan.gerasi...@oracle.com>> wrote:
Hello!
When closing a Process, its stdout and stderr are drained: The
remaining bytes are copied into an array, and then the out/err
stream is replaced with ByteArrayInputStream().
In a case when a fewer number of bytes were read then the
Stream.available() suggested, the array is reallocated with
Arrays.copyOf().
It is possible to avoid reallocation, and use three-args
ByteArrayInputStream() constructor to specify a portion of the
array used.
Would you please help review this trivial fix?
BUGURL: https://bugs.openjdk.java.net/browse/JDK-8203768
<https://bugs.openjdk.java.net/browse/JDK-8203768>
WEBREV: http://cr.openjdk.java.net/~igerasim/8203768/00/webrev/
<http://cr.openjdk.java.net/%7Eigerasim/8203768/00/webrev/>
All existing tests pass on all supported platforms.
Thanks in advance!
--
With kind regards,
Ivan Gerasimov
--
With kind regards,
Ivan Gerasimov
