Sorry I am not receiving emails from core-lib-dev earlier.
What I did was to remove things we considered not absolutely required, which
left us only a StringJoiner class and two String.join methods.
StringJoiner was intended to be used with Stream as a collector, thus prefix,
and suffix is desired like Collection.toString().
Cheers,
Henry
On Apr 19, 2013, at 9:54 AM, Jim Gish <jim.g...@oracle.com> wrote:
> Hi Henry, Can you please comment on the simplifications you did ?
>
> Thanks,
> Jim
>
> On 04/18/2013 07:38 PM, Ulf Zibis wrote:
>> Am 18.04.2013 19:37, schrieb Jim Gish:
>>>
>>> On 04/18/2013 08:49 AM, Ulf Zibis wrote:
>>>> Hi,
>>>>
>>>> I'm wondering, that StringJoiner has some logic for pre/suffix, but
>>>> nothing to loop the elements themselves :-(
>>>>
>>>> To me, StringJoiner is a useless complicated box around StringBuilder, and
>>>> imagine, someone needs thread-safety.
>>>> It also slows down performance, as it needs additional instances and
>>>> additional class to be loaded (critical at VM startup).
>>>>
>>>> Instead please add to StringBuilder and StringBuffer:
>>>> append(CharSequence... elements);
>>>> append(char delimiter, CharSequence... elements);
>>>> append(char delimiter, Iterable<? extends CharSequence> elements);
>>>> cut(int len); // removes len chars at the end of the sequence
>>>> optional:
>>>> append(CharSequence delimiter, CharSequence... elements);
>>>> append(CharSequence delimiter, Iterable<? extends CharSequence> elements);
>>> I started off with something similar, but it was stripped out when Henry
>>> did the performance improvements.
>>
>> Hm, I have no idea, how above suggestions should prevent performance
>> improvements. Can you help me?
>>
>>> Given that most people feel that this is going to be put to heavy-weight
>>> usage, it doesn't seem to merit too much emphasis on performance or
>>> complicating the implementation at this point.
>>
>> Your implementation has
>> 1 class with 7 methods
>> 2 additional methods in String
>> To cover the same functionality, above approach basically only needs 2
>> additional methods in StringBuilder, has better performance, so what is
>> complicated on that?
>>
>> @Martin: What is your opinion?
>>
>> Thanks,
>>
>> -Ulf
>>
>>
>>>> For performance reasons, append should always append the trailing
>>>> delimeter, which could be cut at the end.
>>>>
>>>> It's questionable, if class string needs a static (=no relation to an
>>>> existing string in contrast to non-static split()) join method, as it
>>>> seduces to
>>>> "[" + String.join(...) + "]"
>>>> which needs some effort from javac side to optimize to a single
>>>> StringBuilder task.
>>>> IMO we better had StringBuilder.join(...), so javac could easily optimize
>>>> to:
>>>> new StringBuilder().append('[').append(',',
>>>> someStrings).cut(1).append(']').toString()
>>>>
>>>> -Ulf
>>>>
>>>>
>>>> Am 18.04.2013 00:07, schrieb Martin Buchholz:
>>>>> I'm still wondering about whether a joiner utility should support a prefix
>>>>> and suffix. The obvious uses for this are collection class toString
>>>>> methods, but we already know that we can and should implement those with a
>>>>> single precise char[] construction, so should not use StringJoiner, or at
>>>>> least not this StringJoiner implementation. And if we're just talking
>>>>> about pure convenience, it's hard to beat
>>>>>
>>>>> "[" + String.join(...) + "]"
>>>>>
>>>>>
>>>>> On Wed, Apr 17, 2013 at 2:49 PM, Jim Gish <jim.g...@oracle.com> wrote:
>>>>>
>>>>>> Here's an update: http://cr.openjdk.java.net/~**
>>>>>> jgish/Bugs-5015163-7172553/<http://cr.openjdk.java.net/~jgish/Bugs-5015163-7172553/><
>>>>>>
>>>>>> http://cr.openjdk.java.net/%**7Ejgish/Bugs-5015163-7172553/<http://cr.openjdk.java.net/%7Ejgish/Bugs-5015163-7172553/>
>>>>>>
>>>>>> Jim
>>
>
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> Jim Gish | Consulting Member of Technical Staff | +1.781.442.0304
> Oracle Java Platform Group | Core Libraries Team
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