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Re: Passing a Method Name to a Method, Redux

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On Jul 3, 8:26 pm, blm...@myrealbox.com <blmblm.myreal...@gmail.com>
wrote:
> In article <jcu707d1fb592i91m40fsjtfg0784kn...@4ax.com>,
> Gene Wirchenko  <ge...@ocis.net> wrote:
>
>
>
>
>
>
>
>
>
> > On Thu, 23 Jun 2011 17:24:43 -0700, markspace <-@.> wrote:
>
> > >On 6/23/2011 4:03 PM, Gene Wirchenko wrote:
>
> > >>       So how would you have written this benchmark?
>
> > >Um, realistically?  Is this really what you want to do?
>
> > >  static boolean TreesetSearch( char CurrChar )  {
> > >         return IdentCharsSet.contains( CurrChar );
> > >     }
>
> >      Yes.  I wanted a simple method call in the parser so I could
> > cut-and-paste.  I did not know if I would need more than one call.  I
> > am going to go with a Treeset so I will not have a separate method in
> > the implementation.
>
> Another "no separate method" approach would be to use the String
> class's indexOf method:
>
>     static boolean StringLibSearch
>         (
>          char CurrChar
>         )
>         {
>             return IdentChars.indexOf(CurrChar) >= 0;
>         }
>
> I added this to your benchmark suite and found it to give performance
> comparable to the TreeSet implementation (indeed, usually it was a
> bit faster).  The overhead of building the TreeSet probably doesn't
> matter in the grand scheme of things, and probably it also doesn't
> matter a lot that every call to the TreeSet's "contains" method
> (AFAIK) has to convert a character primitive to a Character object,
> but -- <shrug>.
>
> But if you're going to use a Set, why a TreeSet?  As best I can tell,
> you don't use/need the sorted-ness it provides.  Just out of curiosity,
> I also added to your benchmark suite something that declares the set
> as a Set and creates it as an instance of HashSet, and the resulting
> code was noticeably faster than any of the other alternatives.
>
> And finally, I wondered how all of these methods compared to
> something using regular expressions (the java.util.regex classes), so
> i tried that too, replacing your whole parse code with the following:
>
>     import java.util.regex.*;
>
>     // ....
>
>     static Pattern IdentRegexPattern=Pattern.compile("[" + IdentChars + "]+");
>
>     // ....
>
>     // code to be called repeatedly from timing loop
>     static void ParseRegex()
>     {
>         Matcher IdentMatcher = IdentRegexPattern.matcher(cParseString);
>         String sIdent;
>         while (IdentMatcher.find())
>         {
>             sIdent = IdentMatcher.group();
>             if (nRepetitions==1)
>                 System.out.println(sIdent);
>         }
>     }
>
>     // ....
>
> This was a clear winner (with regard to performance) on the system
> where I measured performance, *unless* I ran the tests with the
> "-server" flag, in which case it took second place, behind the
> HashSet-based approach.  As I understand things, though, the
> "-server" flag results in the compiler doing more to try to optimize
> the code, including being more aggressive about eliminating dead
> code, so I'm not entirely confident about the results I'm getting
> being meaningful.
>
> (Probably your actual code needs to do something other than
> finding and printing identifiers, so the above code would need
> some adjustment.  Still, if you like regular expressions, it's
> another possibility, maybe .... )
>
> [ snip ]
>

Your points are excellent, but the ongoing violations of the naming
conventions is making my brain hurt.  Can't we please revert to
conformant names in our replies at least?

--
Lew

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Thread

Passing a Method Name to a Method, Redux Gene Wirchenko <genew@ocis.net> - 2011-06-23 16:03 -0700
  Re: Passing a Method Name to a Method, Redux Gene Wirchenko <genew@ocis.net> - 2011-06-23 16:26 -0700
    Re: Passing a Method Name to a Method, Redux blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-06-27 21:41 +0000
  Re: Passing a Method Name to a Method, Redux markspace <-@.> - 2011-06-23 17:24 -0700
    Re: Passing a Method Name to a Method, Redux Gene Wirchenko <genew@ocis.net> - 2011-06-23 19:46 -0700
      Re: Passing a Method Name to a Method, Redux blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-04 03:26 +0000
        Re: Passing a Method Name to a Method, Redux lewbloch <lewbloch@gmail.com> - 2011-07-04 03:41 -0700
          Re: Passing a Method Name to a Method, Redux blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-07-05 19:07 +0000
  Re: Passing a Method Name to a Method, Redux markspace <-@.> - 2011-06-23 17:34 -0700
    Re: Passing a Method Name to a Method, Redux Gene Wirchenko <genew@ocis.net> - 2011-06-23 19:42 -0700
  Re: Passing a Method Name to a Method, Redux markspace <-@.> - 2011-06-23 18:30 -0700
    Re: Passing a Method Name to a Method, Redux Gene Wirchenko <genew@ocis.net> - 2011-06-23 19:48 -0700
      Re: Passing a Method Name to a Method, Redux markspace <-@.> - 2011-06-23 21:02 -0700
        Re: Passing a Method Name to a Method, Redux lewbloch <lewbloch@gmail.com> - 2011-06-24 08:38 -0700
          Re: Passing a Method Name to a Method, Redux markspace <-@.> - 2011-06-24 09:04 -0700
            Re: Passing a Method Name to a Method, Redux Lew <noone@lewscanon.com> - 2011-06-26 13:43 -0400
              Re: Passing a Method Name to a Method, Redux Lew <noone@lewscanon.com> - 2011-06-26 14:31 -0400
        Re: Passing a Method Name to a Method, Redux Gene Wirchenko <genew@ocis.net> - 2011-06-24 11:45 -0700
          Re: Passing a Method Name to a Method, Redux markspace <-@.> - 2011-06-24 12:19 -0700
            Re: Passing a Method Name to a Method, Redux Gene Wirchenko <genew@ocis.net> - 2011-06-26 20:39 -0700
              Re: Passing a Method Name to a Method, Redux markspace <-@.> - 2011-06-26 23:33 -0700
                Re: Passing a Method Name to a Method, Redux Gene Wirchenko <genew@ocis.net> - 2011-06-27 13:53 -0700
                Re: Passing a Method Name to a Method, Redux markspace <-@.> - 2011-06-27 18:03 -0700
                Re: Passing a Method Name to a Method, Redux Gene Wirchenko <genew@ocis.net> - 2011-06-28 11:41 -0700
        Re: Passing a Method Name to a Method, Redux blmblm@myrealbox.com <blmblm.myrealbox@gmail.com> - 2011-06-24 19:19 +0000
  Re: Passing a Method Name to a Method, Redux Joshua Cranmer <Pidgeot18@verizon.invalid> - 2011-06-23 19:36 -0700
    Re: Passing a Method Name to a Method, Redux Gene Wirchenko <genew@ocis.net> - 2011-06-24 11:50 -0700
      Re: Passing a Method Name to a Method, Redux Jeff Higgins <jeff@invalid.invalid> - 2011-06-24 17:25 -0400
        Re: Passing a Method Name to a Method, Redux Gene Wirchenko <genew@ocis.net> - 2011-06-26 20:42 -0700
          Re: Passing a Method Name to a Method, Redux markspace <-@.> - 2011-06-26 23:27 -0700
          Re: Passing a Method Name to a Method, Redux Joshua Cranmer <Pidgeot18@verizon.invalid> - 2011-06-27 03:04 -0400
            Re: Passing a Method Name to a Method, Redux Gene Wirchenko <genew@ocis.net> - 2011-06-27 13:12 -0700
              Re: Passing a Method Name to a Method, Redux Joshua Cranmer <Pidgeot18@verizon.invalid> - 2011-06-27 13:36 -0700
      Re: Passing a Method Name to a Method, Redux Joshua Cranmer <Pidgeot18@verizon.invalid> - 2011-06-24 15:50 -0700

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