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Re: for :each style question

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On 12/10/11 4:28 AM, Wanja Gayk wrote:
> In article<iyBBq.2059$2e7.1155@newsfe18.iad>,
> newsgroup.nospam@virtualinfinity.net says...
>
>> I find specific use-cases call for different approaches.  For instance,
>> I like the following for string concatenation:
>>
>> final StringBuilder builder = new StringBuilder();
>>
>> String sep = "";
>>
>> for (Object o: objects) {
>>      builder.append(sep).append(o);
>>      sep = ", ";
>> }
>
> I always preferred to do it this way:
>
> final StringBuilder builder = new StringBuilder();
> final String sep = ", ";
> for (final Object o: objects) {
>      builder.append(o).append(sep);
> }
> builder.setLength(Math.max(0,builder.length()-sep.length()));
>
> The only drawback is that the size of the builder's internal buffer may
> grow unnecessarily, if the last separator crosses its current bounds,
> but how often does that happen and how often is it really a problem?
The *only* drawback?  Having to invoke a "Math" command is a drawback 
IMO. I like my approach because you can have a different starting 
separator.    Consider the case where you want parenthesis for one or 
more items, but an empty string for no items.:

String ender = "";
String sep = "(";
for (Object o: objects) {
    builder.append(sep).append(o);
    sep=", "; end=")";
}
builder.append(end);

Builds a parenthesized comma-separated list.  I have used this pattern 
frequently for SQL or HQL query builders.

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for :each style question Roedy Green <see_website@mindprod.com.invalid> - 2011-11-30 15:32 -0800
  Re: for :each style question Arne Vajhøj <arne@vajhoej.dk> - 2011-11-30 19:28 -0500
    Re: for :each style question Chris Riesbeck <Chris.Riesbeck@gmail.com> - 2011-12-05 14:28 -0600
  Re: for :each style question Knute Johnson <nospam@knutejohnson.com> - 2011-11-30 16:49 -0800
    Re: for :each style question Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2011-11-30 18:23 -0800
      Re: for :each style question Wanja Gayk <brixomatic@yahoo.com> - 2011-12-10 13:28 +0100
        Re: for :each style question Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2011-12-12 12:07 -0800
          Re: for :each style question Roedy Green <see_website@mindprod.com.invalid> - 2011-12-13 08:08 -0800
            Re: for :each style question Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2011-12-13 12:07 -0800
          Re: for :each style question Wanja Gayk <brixomatic@yahoo.com> - 2011-12-17 16:20 +0100
        Re: for :each style question Jim Janney <jjanney@shell.xmission.com> - 2011-12-14 14:31 -0700
          Re: for :each style question Lew <lewbloch@gmail.com> - 2011-12-14 16:53 -0800
            Re: for :each style question Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2011-12-15 16:16 -0800
          Re: for :each style question Wanja Gayk <brixomatic@yahoo.com> - 2011-12-17 12:31 +0100
  Re: for :each style question Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-11-30 21:35 -0500
  Re: for :each style question Lew <lewbloch@gmail.com> - 2011-11-30 19:12 -0800
  Re: for :each style question Robert Klemme <shortcutter@googlemail.com> - 2011-12-01 23:36 +0100
  Re: for :each style question Steven Simpson <ss@domain.invalid> - 2011-12-04 19:43 +0000

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