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/ 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 > >
