Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > comp.lang.java.programmer > #4358

Re: Did the sort do anything?

Date 2011-05-20 05:20 -0700
From Patricia Shanahan <pats@acm.org>
Newsgroups comp.lang.java.programmer
Subject Re: Did the sort do anything?
References (11 earlier) <ZOOdndoMvN_sA0zQnZ2dnUVZ_v6dnZ2d@earthlink.com> <iqt73d$dqg$2@lust.ihug.co.nz> <kYCdnSqcI7kP40_QnZ2dnUVZ_gydnZ2d@earthlink.com> <ir52p0$ups$2@lust.ihug.co.nz> <vaGdna9HCu5lykvQnZ2dnUVZ_hKdnZ2d@earthlink.com>
Message-ID <e5CdnR_-upYpwUvQnZ2dnUVZ_uSdnZ2d@earthlink.com> (permalink)

Show all headers | View raw


On 5/20/2011 5:00 AM, Patricia Shanahan wrote:
> On 5/19/2011 11:46 PM, Lawrence D'Oliveiro wrote:
>> In message<kYCdnSqcI7kP40_QnZ2dnUVZ_gydnZ2d@earthlink.com>, Patricia
>> Shanahan wrote:
>>
>>> Now that we have clarified the fact that System.identityHashCode(x) is
>>> not merely a synonym for x.hashCode(), have you changed your mind about
>>> the need, or otherwise, for stability when sorting Java objects based on
>>> the entire value of the object's fields?
>>
>> What do you think I said about “the need, or otherwise, for stability”?
>
> "If, on the other hand, you were sorting immutable objects of a Java
> “reference” type where the key was the entire object state, then
> stability would indeed be irrelevant, notwithstanding such types are not
> considered “primitive”."
>
> [http://groups.google.com/group/comp.lang.java.programmer/msg/17e3a8e513ceab46]

To further refresh your memory, the question I raised was whether you
consider System.identityHashCode(x) to be part of the "entire object
state" of the object referenced by x.

If the answer is "yes", then sorts whose key is the entire object state
are so extremely rare that I've never seen one.

If the answer is "no", then even if the sort key is the entire object
state, the subsequent program behavior, such as the performance of an
IdentityHashMap, can be affected by whether the sort is stable or not,
so stability is relevant.

Patricia

Back to comp.lang.java.programmer | Previous | NextPrevious in thread | Next in thread | Find similar


Thread

Did the sort do anything? Roedy Green <see_website@mindprod.com.invalid> - 2011-05-10 08:06 -0700
  Re: Did the sort do anything? markspace <-@.> - 2011-05-10 08:48 -0700
    Re: Did the sort do anything? Lawrence D'Oliveiro <ldo@geek-central.gen.new_zealand> - 2011-05-14 15:33 +1200
      Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-14 08:56 -0400
        Re: Did the sort do anything? Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2011-05-14 13:54 +0000
          Re: Did the sort do anything? Lawrence D'Oliveiro <ldo@geek-central.gen.new_zealand> - 2011-05-15 11:16 +1200
      Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-14 23:24 -0400
        Re: Did the sort do anything? Tom Anderson <twic@urchin.earth.li> - 2011-05-15 11:20 +0100
          Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-15 07:00 -0400
            Re: Did the sort do anything? Tom Anderson <twic@urchin.earth.li> - 2011-05-15 15:09 +0100
              Re: Did the sort do anything? Lawrence D'Oliveiro <ldo@geek-central.gen.new_zealand> - 2011-05-16 14:28 +1200
                Re: Did the sort do anything? Joshua Cranmer <Pidgeot18@verizon.invalid> - 2011-05-15 22:38 -0400
                Re: Did the sort do anything? Lawrence D'Oliveiro <ldo@geek-central.gen.new_zealand> - 2011-05-16 19:11 +1200
                Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-16 03:47 -0400
                Re: Did the sort do anything? markspace <-@.> - 2011-05-16 14:14 -0700
                Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-15 22:40 -0400
                Re: Did the sort do anything? Tom Anderson <twic@urchin.earth.li> - 2011-05-16 21:31 +0100
                Re: Did the sort do anything? Lawrence D'Oliveiro <ldo@geek-central.gen.new_zealand> - 2011-05-17 09:12 +1200
                Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-16 17:24 -0400
                Re: Did the sort do anything? Tom Anderson <twic@urchin.earth.li> - 2011-05-17 13:26 +0100
          Re: Did the sort do anything? markspace <-@.> - 2011-05-15 04:56 -0700
            Re: Did the sort do anything? Tom Anderson <twic@urchin.earth.li> - 2011-05-15 15:12 +0100
              Re: Did the sort do anything? markspace <-@.> - 2011-05-15 07:52 -0700
          Re: Did the sort do anything? Michael Wojcik <mwojcik@newsguy.com> - 2011-05-18 11:14 -0400
            Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-18 13:02 -0400
            Re: Did the sort do anything? Lawrence D'Oliveiro <ldo@geek-central.gen.new_zealand> - 2011-05-20 18:49 +1200
              Re: Did the sort do anything? Robert Klemme <shortcutter@googlemail.com> - 2011-05-20 00:06 -0700
                Re: Did the sort do anything? Lawrence D'Oliveiro <ldo@geek-central.gen.new_zealand> - 2011-05-20 22:37 +1200
                Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-20 07:09 -0400
  Re: Did the sort do anything? Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2011-05-10 16:11 +0000
  Re: Did the sort do anything? Daniele Futtorovic <da.futt.news@laposte-dot-net.invalid> - 2011-05-10 21:26 +0200
    Re: Did the sort do anything? Tom Anderson <twic@urchin.earth.li> - 2011-05-11 21:38 +0100
      Re: Did the sort do anything? Daniele Futtorovic <da.futt.news@laposte-dot-net.invalid> - 2011-05-11 23:27 +0200
      Re: Did the sort do anything? Roedy Green <see_website@mindprod.com.invalid> - 2011-05-13 07:40 -0700
        Re: Did the sort do anything? Spock <spock@starfleet.ufp> - 2011-05-13 16:56 -0400
        Re: Did the sort do anything? Lawrence D'Oliveiro <ldo@geek-central.gen.new_zealand> - 2011-05-15 13:58 +1200
          Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-14 23:27 -0400
  Re: Did the sort do anything? Robert Klemme <shortcutter@googlemail.com> - 2011-05-11 20:40 +0200
    Re: Did the sort do anything? Joshua Cranmer <Pidgeot18@verizon.invalid> - 2011-05-12 10:40 -0400
      Re: Did the sort do anything? Robert Klemme <shortcutter@googlemail.com> - 2011-05-13 03:50 -0700
      Re: Did the sort do anything? Roedy Green <see_website@mindprod.com.invalid> - 2011-05-13 07:46 -0700
        Re: Did the sort do anything? Lawrence D'Oliveiro <ldo@geek-central.gen.new_zealand> - 2011-05-16 14:32 +1200
          Re: Did the sort do anything? Patricia Shanahan <pats@acm.org> - 2011-05-15 19:50 -0700
            Re: Did the sort do anything? Lawrence D'Oliveiro <ldo@geek-central.gen.new_zealand> - 2011-05-16 17:57 +1200
              Re: Did the sort do anything? "javax.swing.JSnarker" <gharriman@boojum.mit.edu> - 2011-05-16 03:35 -0400
              Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-16 03:44 -0400
              Re: Did the sort do anything? Patricia Shanahan <pats@acm.org> - 2011-05-16 03:53 -0700
                Re: Did the sort do anything? Lawrence D'Oliveiro <ldo@geek-central.gen.new_zealand> - 2011-05-17 00:02 +1200
                Re: Did the sort do anything? "javax.swing.JSnarker" <gharriman@boojum.mit.edu> - 2011-05-16 08:05 -0400
                Re: Did the sort do anything? Lawrence D'Oliveiro <ldo@geek-central.gen.new_zealand> - 2011-05-17 09:12 +1200
                Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-16 17:32 -0400
                Re: Did the sort do anything? thoolen <thoolen@tholenbot.thorium> - 2011-05-16 18:09 -0400
                Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-16 10:02 -0400
                Re: Did the sort do anything? Patricia Shanahan <pats@acm.org> - 2011-05-16 07:16 -0700
                Re: Did the sort do anything? Lawrence D'Oliveiro <ldo@geek-central.gen.new_zealand> - 2011-05-17 09:11 +1200
                Re: Did the sort do anything? Patricia Shanahan <pats@acm.org> - 2011-05-16 15:00 -0700
                Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-16 21:08 -0400
                Re: Did the sort do anything? Lawrence D'Oliveiro <ldo@geek-central.gen.new_zealand> - 2011-05-17 19:11 +1200
                Re: Did the sort do anything? Patricia Shanahan <pats@acm.org> - 2011-05-17 02:34 -0700
                Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-17 07:19 -0400
                [OT] Naming conventions. Was: Re: Did the sort do anything? Patricia Shanahan <pats@acm.org> - 2011-05-17 06:52 -0700
                Re: Naming conventions. Was: Re: Did the sort do anything? Robert Klemme <shortcutter@googlemail.com> - 2011-05-18 01:22 -0700
                Re: Naming conventions. Was: Re: Did the sort do anything? Patricia Shanahan <pats@acm.org> - 2011-05-18 03:42 -0700
                Re: Naming conventions. Was: Re: Did the sort do anything? RedGrittyBrick <RedGrittyBrick@spamweary.invalid> - 2011-05-18 11:53 +0100
                Re: Naming conventions. Was: Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-18 13:07 -0400
                Re: Naming conventions. Was: Re: Did the sort do anything? Patricia Shanahan <pats@acm.org> - 2011-05-18 10:37 -0700
                Re: Naming conventions. Was: Re: Did the sort do anything? Heike Svensson <hsvensson.1093x1_q@hotmail.nospam.com.please> - 2011-05-19 01:29 -0400
                Re: Naming conventions. Was: Re: Did the sort do anything? Robert Klemme <shortcutter@googlemail.com> - 2011-05-19 08:28 +0200
                Re: Naming conventions. Was: Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-19 08:50 -0400
                OT: National stereotypes. Was Re: Naming conventions. Was: Re: Did the sort do anything? RedGrittyBrick <RedGrittyBrick@spamweary.invalid> - 2011-05-23 10:25 +0100
                Re: OT: National stereotypes. Was Re: Naming conventions. Was: Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-23 09:05 -0400
                Re: OT: National stereotypes. Was Re: Naming conventions. Was: Re: Did the sort do anything? RedGrittyBrick <RedGrittyBrick@spamweary.invalid> - 2011-05-23 17:17 +0100
                Re: OT: National stereotypes. Was Re: Naming conventions. Was: Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-23 14:43 -0400
                Re: OT: National stereotypes. Was Re: Naming conventions. Was: Re: Did the sort do anything? Steve Sobol <sjsobol@JustThe.net> - 2011-05-23 08:27 -0700
                Re: OT: National stereotypes. Was Re: Naming conventions. Was: Re: Did the sort do anything? RedGrittyBrick <RedGrittyBrick@spamweary.invalid> - 2011-05-23 17:39 +0100
                Re: OT: National stereotypes. Was Re: Naming conventions. Was: Re:   Did the sort do anything? Robert Klemme <shortcutter@googlemail.com> - 2011-05-23 19:16 +0200
                Re: OT: National stereotypes. Was Re: Naming conventions. Was: Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-23 14:47 -0400
                Re: Did the sort do anything? Boojum <boojum42@gmai1.c0m> - 2011-05-18 07:19 -0400
                Re: Did the sort do anything? Lawrence D'Oliveiro <ldo@geek-central.gen.new_zealand> - 2011-05-20 18:46 +1200
                Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-20 07:10 -0400
                Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-17 07:16 -0400
                Re: Did the sort do anything? Patricia Shanahan <pats@acm.org> - 2011-05-17 06:56 -0700
                Re: Did the sort do anything? Lawrence D'Oliveiro <ldo@geek-central.gen.new_zealand> - 2011-05-20 18:46 +1200
                Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-20 07:11 -0400
                Re: Did the sort do anything? Patricia Shanahan <pats@acm.org> - 2011-05-20 05:00 -0700
                Re: Did the sort do anything? Patricia Shanahan <pats@acm.org> - 2011-05-20 05:20 -0700
                Re: Did the sort do anything? Lawrence D'Oliveiro <ldo@geek-central.gen.new_zealand> - 2011-05-21 09:56 +1200
                Re: Did the sort do anything? Lew <noone@lewscanon.com> - 2011-05-20 18:12 -0400
                Re: Did the sort do anything? Patricia Shanahan <pats@acm.org> - 2011-05-20 21:26 -0700
                Re: Did the sort do anything? Gheerax IV <gheerax.4@gmail.invalid> - 2011-05-17 06:58 +0000
                Re: Did the sort do anything? Unitary Matrix <umatrix668@gmail.com> - 2011-05-17 00:13 -0700
                Re: Did the sort do anything? markspace <-@.> - 2011-05-17 07:41 -0700
    Re: Did the sort do anything? Roedy Green <see_website@mindprod.com.invalid> - 2011-05-13 07:42 -0700
      Re: Did the sort do anything? Robert Klemme <shortcutter@googlemail.com> - 2011-05-13 21:28 +0200
  Re: Did the sort do anything? Tom Anderson <twic@urchin.earth.li> - 2011-05-11 21:32 +0100

csiph-web