On 07/19/2014 05:58 PM, Martin Buchholz wrote:
StringJoiner seems written in a style suitable for an application, not in a
low-level performance-oriented style suitable for a JDK core library. But
we can fix that.
http://cr.openjdk.java.net/~martin/webrevs/openjdk9/StringJoiner-optimization/
Hi Martin,
it's not obvious for me that your implementation is more efficient,
if you have a lot of strings, because you store reference to them, you
will have references
everywhere on heap so toString() will not be very cache friendly.
The current implementation that use a StringBuilder will consume more
memory but
is more cache friendly.
otherwise, your implementation of merge is weird (or half weird), unlike
add,
for merge you combine all strings into a unique big string instead of
merging
the two arrays, is there a reason for that ?
regards,
Rémi
On Fri, Jul 18, 2014 at 6:18 PM, Ivan Gerasimov <ivan.gerasi...@oracle.com>
wrote:
On 19.07.2014 3:07, Martin Buchholz wrote:
I took a quick look at StringJoiner. It looks to me like this won't be
an optimization, because StringJoiner uses StringBuilder internally, and
will actually perform more total operations.
Unfortunately this is true.
Microbenchmarking shows that StringJoiner makes the things 30% slower,
which is sad.
Then I propose another simple patch giving +15% to the speed:
http://cr.openjdk.java.net/~igerasim/8051382/1/webrev/
Sincerely yours,
Inan
