It is natural to compare StringJoiner with guava Joiner. http://docs.guava-libraries.googlecode.com/git/javadoc/com/google/common/base/Joiner.html Joiner is popular and has stood the test of time.
Joiner designers chose not to include a prefix and suffix, presumably because that is an independent concern - it's not a "joining" activity. OTOH, I'm guessing you are trying to improve the performance of operations like List.toString. More efficient (single copy char[]) would be to collect all the sub-CharSequences in a CharSequence[], pre-compute the final length of the char[], allocate an array of exactly the required length, and create the final string directly from that using the package-private constructor (but in the unlikely event that a subsequence changed in size while concat'ing, be prepared to resize the array). On Thu, Apr 11, 2013 at 3:33 PM, Jim Gish <jim.g...@oracle.com> wrote: > Please review http://cr.openjdk.java.net/~**jgish/Bugs-5015163-7175206-** > 7172553/ <http://cr.openjdk.java.net/~jgish/Bugs-5015163-7175206-7172553/>< > http://cr.openjdk.java.net/%**7Ejgish/Bugs-5015163-7175206-**7172553/<http://cr.openjdk.java.net/%7Ejgish/Bugs-5015163-7175206-7172553/> > > > > These are changes that we made in lambda that we're now bringing into JDK8. > > I've made a couple of additions - making StringJoiner final and adding a > couple of constructors to set the emptyOutput chars. > > Thanks, > Jim > > -- > Jim Gish | Consulting Member of Technical Staff | +1.781.442.0304 > Oracle Java Platform Group | Core Libraries Team > 35 Network Drive > Burlington, MA 01803 > jim.g...@oracle.com > >
